| WELCOME to the anvilfire Guru's Den - V. 3.0 |
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THIS is a forum for questions and answers about blacksmithing and general metalworking. Ask the Guru any reasonable question and he or one of his helpers will answer your question, find someone that can, OR research the question for you. This is an archive of posts from May 10 - 18, 2004 on the Guru's Den |
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T.Gold: Yep, pure iron scales just as bad. Scale has nothing to do with carbon content, it is just iron oxide. Any time you heat iron/steel in an oxygen-containing atmosphere, it will scale. |
| Alan-L - Monday, 05/10/04 00:27:43 EDT |
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Vance I have been forge welding logging cable for some time. it is wire stranded cable. Flux it up like normal, just alot, to make sure it gets to the center. you will want to spin/rotate the cable as it heats so that the heat also reaches the middle without burning the outsides. try to hammer it evenly on both sides. the key is rotation. I hit 2x then rotate. If you keep it square it is much wasier to fold back over and weld. As to carbon content The Hammer-In as answered that question(that is if your cable is logging cable) |
| Joe R - Monday, 05/10/04 02:41:14 EDT |
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Ah, thanks for the info Alan. |
| T. Gold - Monday, 05/10/04 03:01:38 EDT |
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Guru Just managed to read up to your post about the 180mm disc grinder. Vibration is normal, and my shop teacher is one of the best. We have old equipment due to budget constraints but he keeps everything in good safe working order. The vibration from the grinder is smooth, does not visibly shake my arms at all. Even the under-developed freshmen in the class can use it without visible vibration. They can only hang with short bursts though...lol it is a heavy piece of machinery... even I have notice the weight after a few minutes, and I am an all-state defensive lineman...hehe |
| Joe R - Monday, 05/10/04 03:06:19 EDT |
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Just a note to add to guru's post on motor overloads: in new construction any circuit that is feeding a motor is suposed to be a stand alone circuit (one receptacle on the line, nothing else). This even applies to household washing machine. The current draw for even a light motor at starting is sufficiently high that even a light bulb on that circuit can cause a breaker to trip under the right conditions |
| - Ed Long - Monday, 05/10/04 07:43:22 EDT |
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I am a dabbling blacksmith whose been using coal for years, and now I want to build a gas forge.I've browsed just about every forge design available for free on the net and your site, specifically Ron Reil's burner and forge designs. I have a limited budget and was wondering if using HICR refractory, a mixture of pearlite and furnace cement(rated 3000F) would be an acceptable alternative to the difficult to find and more expensive kaowool. Would I need to use ITC 100 with the HICR if I wanted to obtain a welding heat without multiple/oversized burners? The info on the HICR can be found at http://www.john-wasser.com/NEMES/MakeICR.html Mr Wasser has used this refractory to melt 1 1/2 lbs of aluminum in twenty minutes consuming 6 ounces of propane. I'm also concerned that building a horizontal-cylindrical forge will limit the size of what I can fit through the door.Do you think this homemade refractory could work in a forge similar to the Whisper Momma? What are the pros/cons of oven-style forges vs cylinders? p.s. If anyone has info on where to get cheap propane regulators suitable for this project please email |
| David S - Monday, 05/10/04 09:22:36 EDT |
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David, I have bought several regulators at fleamarkets; bot propane and acetylene ones for around $5. You have to check them for leaks; but I've been lucky so far and have not had any bad ones. A adjustable propane regulator is not that expensive (under $30) even if bought new. As I'm sure you know gas grill regulators do not work for forges. Thomas |
| - Thomas P - Monday, 05/10/04 11:29:24 EDT |
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I am currentley at the HCT in hereford, studing a first diploma in blacksmithing, and I have come across a problem of joining metal other than fire welding or welding |
| John Langley - Monday, 05/10/04 11:30:28 EDT |
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Q-oils: I bought one 5 gallon bucket of Texaco quench oil many years ago and keep it in an old milk bucket. It has a tight fitting lid on a short chain that can be flipped over in case of a fire and also keeps moisture out. The quench oils will burn but their flash point is somewhat higher than motor oil. Blowers - Coal and coke requires pressure and CFM so some type of centrifigual blower is needed and 250 to 400 cfm is adequate. Squirrel cage blowers "work" to a degree but are not as satisfactory as a paddle-type fan. Squirrel cages work well on gas forges where no mass of coke has to be overcome to allow proper burning of the fuel. |
| - HWooldridge - Monday, 05/10/04 11:48:42 EDT |
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David S. unless you get you propane for free I would strongly consider the kaowool and ITC 100 combination. The time and cost of getting castable up to heat I found very expensive. If you are a production shop and time is worth more than fuel, the castable is possibly a better way to go. I usually reline my forges about once a year (smithing full time) I buy kaowool by the box (1”, 50 sq ft) and ITC 100 by the pint. I wished I lived in the States and could buy at your great prices, I see you can buy a box of Kaowool here (Anvilfire Store) for $89.75 and ITC 100 for $32.50 a pint, I pay over a $100.00 for the wool and $80.00 USD for the ITC. It may seem like a lot, but the wool will make approximately 7- 20# tank style forges and the ITC will do even more, So a cost of $17.50 per forge. If you factor in that your time is worth $5.00 an hour as hobbyist you have most likely paid for it after 7 firings. Since I have the wool on hand most times, I have made forges in different sizes. In the summer I do a lot of steak turners. So I made a small forge to work on them it uses a smaller burner as well and the shop doesn’t get as hot. Sorry for the long post. |
| - Daryl - Monday, 05/10/04 12:05:02 EDT |
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Vance Moore, I am not an expert on welding cable, but have had success. I learned from an expert bladesmith at a hammer-in some years ago. His technique was to get the cable warm to red, then ladle on the borax. Lots of borax! Heat to welding temp. Hammer in the direction of the twist to keep the cable tight. If it loosens, just tighten it up by twisting. Flux with borax every heat. You can only weld about 3/4 |
| - ptree - Monday, 05/10/04 12:29:24 EDT |
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Routers, Firewalls, Windows, and Internet Security One thing I stress to my clients is to know what your computer is doing. Windows NT,2000, and XP have a Task List/Manager that will tell you all the processes running on your machine. You should check this on occasion and learn what should and should not be running. There are a lot of websites that will tell you what a process is and if it is a virus. Just do a search for the process name. Also, make sure your file extensions (i.e. .doc .exe .scr) are turned on and learn what they mean. In Windows you can make sure they are on in Folder Options, it is under Tools or View in My Computer depending on the ver. you are running. A lot of viruses come in emails like this: filename.doc.exe. If you have the extensions turned off all you see is filename.doc and it looks like a Word document. Routers and firewalls allow you to access the Internet but block the Internet from accessing you. If you have a setup like this it is also important that your Internet Address (TCP/IP) setting on your computer(s) are in the form of 192.168.#.#, the 192.168. beginning octet is not accessible from the internet and the last # is unique to each computer. The third # either usually denotes what network segment you are on, but that usually does not apply to home and should be the same on all the computers. Your Router usually gets its address from your service provider and then assigns addresses to your computer(s) based on a set range. If that range does not begin 192.168 you could be opening your gates to the world. Most inexpensive home routers are already set this way and cannot changed. Linksys is a good value and have good customer support and is what I usually suggest for most homes on a 24/7 connection. As always, when in doubt call a pro or the customer support #. With Microsoft they have an extensive Knowledge Base to explain their plethora of problems and some possible fixes. |
| Shack - Monday, 05/10/04 12:37:34 EDT |
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Daryl, Informational/experience based posts such as yours are very important, and only rarely are they too long. Yours was excellent in all regards. |
| Paw Paw - Monday, 05/10/04 12:43:44 EDT |
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Thomas thank you for the great suggestion about fleamarkets I will definitely check that out. Daryl - thanks for the good advice,do you double up the 1" kaowool in your freon tank forges? How many linear feet of the 24" wide blanket do I need for this? Would half a pint of ITC 100 be enough? I've found a supplier that sells half pints for $17 Thanks again |
| David S - Monday, 05/10/04 12:48:37 EDT |
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David S. No I don't live on the computer, but came in to grab coffee, had ice on the slack tub (okay it was outside). I use a minimum of 2 wraps of one inch. On a shell the size of a 20# I think you guys call a 5 gallon propane tank (this is just for sizing I don't cut propane tanks unless some one gives me one cut open) I use just over 7 sq ft of kaowool. It would really depend on your configuration. I think 3"s might even be better, I believe that is what is in Swan forges, and I was leaning on one and then it dawned on be it was on. A half pint of ITC would do several forges. To cure the ITC I use a old electric BBQ lighter like the one the kid used on the door knob of movie "Home Alone". As for forge welding in a propane forge I have no problem with billets but for everthing else I have problems, so I get my 13yr old to do it. |
| - Daryl - Monday, 05/10/04 13:10:59 EDT |
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Difficult to find and expensive Kaowool??? David, we sell Kaowool here by the foot and by the box. It IS a little more expensive than other refractories but what you get in exchange is high efficiency and light weight. A forge or furnace you can pick up with one hand and walk off with is VERY handy. We also sell ITC products to coat refractories and metal. I have made the mistake of trying to stretch and lighten castable refactory by adding a small amount vermiculite. The result was a weak material that has had to be patched every time it was fired. You CAN do these things but like all R&D they can be expensive experiments. The limitation of gas forges is always the enclosure. To be efficient you need one for every size work. Ingenuity also helps. One of the best forge modifications I have see was a standard long front door with end port forge that was converted to a "C" shape WITH door. Long pieces can be stuck through but long pieces with a big scroll or some odd shape can be but in through the door and stick out the end ports. This was a VERY nifty mod by Dean Curfman, professional smith and maker of BigBLU hammers. If you want a cheap hard refractory forge use firebrick. Stack them or enclose in a frame or box. Be darn sure to turn them ALL so that you have a minimum of 4-1/2" of wall thickness. Turned the short direction they result in a forge that is like standing in front of a wall of flame. It also makes a VERY heavy forge. For melting I have built several little furnaces from Freon cans. These will hold a #1 crucible (3.2 pounds brass) and do a full melt of brass in about 5-10 minutes (5 after the first heat). I haven't measured the gas consumption but it is less than my NC Whisper-baby forge. Furnaces for melting and forging are VERY similar but are best built to the proper configuration for the purpose. One HANDY trick for small melters is to use half or more of the container as lid. This works great with a light weight Kaowool lining. Regular melting furnaces use a small thin lid due the weight of solid refractories. But this is not a concern when you can ligt the whole furnace with one hand. The reason this is so handy is that you do not need two different pairs of tongs to handle the crucible. To remove a crucible from a standard crucible furnace you must have special vertical lift crucible tongs. THEN to pour you need side grip tongs OR a pouring shank. When you lift the top half of the crucible furnace you can use one pair of tonges to remove the crucible AND do the pour. This CAN be done with solid refractory but the top half must be built on sturdy counter balanced arms. A lot of extra (expensive) mechanism. ITC-100 is recommended to coat all refractories to increase efficiency. Kaowool exposed to flame in forges and furnaces should be coated with ITC-100 to prevent spreading of possibly carcenogenic dust. See our FAQ's page article on Gas Forges and the iForge article on lost wax casting. I am working on an article on casting but had a bunch of failures before having successes to show off. |
| - guru - Monday, 05/10/04 13:47:21 EDT |
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$17 ITC-100: David, ITC-100 is not factory packed in anything less than pints. Those repackaging the product are lible to lose their distributorship if they have not already. We had planned on putting together repair kits with small quantites of the relatively expensive ITC-213 and 296-A but backed off when we were told we would lose our distributorship. |
| - guru - Monday, 05/10/04 13:59:38 EDT |
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Welding Cable (IE Wire Rope): Vance, If you have any problems with this the Wayne Goddard's "The Wire Damascus Hunting Knife" video is VERY good. Some pointers from the video or DVD: 1) Start with clean cable. Old rusted cable is very difficult to weld. 2) Flux early, often and copiously. 3) Twist the hot cable to close it up before the welding heat. 4) Weld gently at first then heavier to close up. The video has dozens more hints and ideas. It is an excelent companion to his popular $50 Knife shop. |
| - guru - Monday, 05/10/04 14:16:11 EDT |
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Anvils to Identify: These are for our European friends to help identify. Richard Postman has looked at these but I am not sure he is right. The owner is looking for approximate age and place of manufacture. -guru  Signed old European anvil I picked up a couple rather unique "church window" anvils this weekend. This one is about 250lbs. and has a name and date inscribed on it (also note the placement of the hardy hole). The anvil reads, C : BOUIUS 1819 I am certain the first "u" is not a "v" since the bottom is distinctly rounded. According to Richard Postman (who saw it a couple of years ago), he feels the anvil is German and the name is one of the previous owners. He feels the date represents when that person obtained it rather than the date of manufacture. Does anyone have any information or an interpretation of "C : BOUIUS" ? What it might mean?"  Old European double horned anvil This anvil is supposedly French in origin and is thought to be an armor-makers anvil. It weighs 414lbs. and has very deep "church windows" and is completely flat on the side opposite the "windows". Which means it could lay flat with the windows facing up to use them for dishing and rounding. Anyone have any thoughts? Take .lastname and put it after my first name to mail. |
| Paul P. - Monday, 05/10/04 15:36:32 EDT |
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Another possible Armourer's anvil Note that this one also can be laid on its back. |
| - guru - Monday, 05/10/04 15:55:19 EDT |
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Can you tell me what a red short heat is and how I would recognize its effects on a piece of iron? Thanks |
| Gary Hilton - Monday, 05/10/04 16:54:41 EDT |
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Just out of curiosity, what would be the effect of "doping" the propane supply to a forge burner with bottled O2? Would it lower the propane consumption without degrading the performance of the forge?? What about adding acetalyne to the mix?? |
| HavokTD - Monday, 05/10/04 18:31:10 EDT |
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Oxygen Enriched Forge: HavokTD, it would run much hotter as well as be more oxidizing. In gas forges oxidation is a problem and difficult to control. Adding oxygen would make it worse. Run a forge like an oxy-propane torch and you will have steel (and refractory) melting temperatures. Hotter gas is already available in the form of MAPP gas a mixture of Propane, natural gas (I think) and acetylene among other things. |
| - guru - Monday, 05/10/04 18:41:57 EDT |
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would the oxidisation effect be compinsated for by the fact that the steel would be in the fire for a lot shorter time span?? |
| HavokTD - Monday, 05/10/04 18:46:15 EDT |
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Wow, I need to learn how to spell, sorry about that, all. |
| HavokTD - Monday, 05/10/04 18:46:54 EDT |
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Red Short: Gary, this is not a heat, it is a condition of metals where they are brittle and fall apart while worked at a red heat. It is usualy caused by improper alloying or oxide impurities. Metals that are red short need to be worked at higher temperatures than a red heat. |
| - guru - Monday, 05/10/04 18:56:45 EDT |
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HavokTD, Since scaling is already a problem more O2 would probably make it worse. A LOT depends on the configuration of the forge, how much mass it has, preheat, available BTU. . . Many small gas forges do not have sufficient BTU to keep up with the heat loss and thus must be run hard and lean to get hot enough. Running rich reduces the oxidation but also reduces the temperature. Everything must be a balance. If you want a non-solid fuel forge that runs HOT and non-oxidizing you want an oil forge. These run on kerosene, #2 fuel oil and or diesel. They are much easier to run at a carburizing condition (rich) but they stink even worse when doing so. |
| - guru - Monday, 05/10/04 19:03:10 EDT |
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Thanks, Guru. I was actually just trying to fgure out a way to cheap out on the fuel. :-) |
| HavokTD - Monday, 05/10/04 19:07:55 EDT |
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MAPP Methane Acetylene ProPane |
| Paw Paw - Monday, 05/10/04 19:10:38 EDT |
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MAPP...Methyl acetylene-propadiene mixture. |
| - Robert-ironworker - Monday, 05/10/04 23:26:26 EDT |
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I have a titan gas Kerosene hit and miss engine in 1 HP.I bought it to restore.Both crank shaft babbet bearings are missing top and bottom.I would like to pour new bearings myself.where can I fine info on doing this project?I have babbet.I also have a tourch and a melting furnace and most everything I need.My dad use to do this but he is no longer alive.I am certain I have all the abilities to do this but need some directions.Thank You. George.... |
| George Cook - Monday, 05/10/04 23:44:56 EDT |
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Forge blowers: Thanks for the info. Will save up for the stronger unit. ET |
| - Eric T - Tuesday, 05/11/04 00:49:00 EDT |
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GEORGE COOK; All kinds of how-to info on babbit at Lindsay Publications |
| 3dogs - Tuesday, 05/11/04 05:25:48 EDT |
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A few locations of info on babbit: http://www.jedc.org/wood/Spring_2000.pdf I saw a reference that said the Machinery Handbook had a section on it. I will have to look when I get home |
| Ralph - Tuesday, 05/11/04 09:42:06 EDT |
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Babbiting: Older editions of MACHINERY'S HANDBOOK (1950's) have in depth articles about babbiting. Later editions have short articles. There are two ways. One is to fit the shaft, the other is to fit an undersized mandrel and then machine or ream the babbit to fit the shaft. The second method was probably used on the engine originaly. I will describe the first. Step one is to find a way to hold the shaft in perfect alignment. In old cast journals the alignment is probably NOT the center of the journals but may be. It will take some reverse engineering to find the alignment. Be sure the journals are very clean and oil free. Ocassionaly it is recommended to tin the journals first. But rough cast journals are usualy OK. SOOT the shaft. A candle works and so does a acetylene flame. The soot keeps the babbit from sticking to the shaft and provides oil clearance. It takes quite a bit of soot. Install and align the shaft. Then dam up the edges. Daming is done with daming compound, a heat sticky heat resistant clay. It also helps to use sheet metal cut to fit the shaft. Warm the shaft and housing gently with a torch. A cold housing will chill the babbit and prevent a good poor. Melt the babbit until it is hot enough to char a pine stick. Continue to warm the shaft and housing, putting more heat into the housing. Do not exceed the boiling point. Skim the dross off the babbit. Pour the bottom halves of the bearings and let chill. An uninterupted pour is best, keep pouring until the babbit stops shrinking and you have a raised surface (if possible). Remove the shaft and trim the bottom babbit flush to the case. Clean and resoot the shaft. Install in the lower bearings and seat with a wooden mallet. Install the bearing caps AND shims. You will need a fine shim set for each bearing a total of about .015" thick. These should ALMOST contact the shaft but not quite. Dam up the caps, heat melt and pour as above. Caps are usualy poured through the oil port. Those that do not have a port must be poured from the end which means having the shaft vertical and clamped in place. Remove the caps and shims. Drill out the oil port. Cut oil grooves with an oil groove scraper (you will have to make your own). A rough babbit surface is often hand scraped and the shims used to adjust the running clearance. This is real machine fitters art and VERY picky work. Often the surface of a poured babbit bearing has surface tension lines (like folds). There is not much you can do about these. For perfect bearings they use the mandrel and machining method to have bright clean babbit. The "machining" was often just a reaming process. But this took heavy alignment fixtures (which were often the pouring fixtures). Good Luck! |
| - guru - Tuesday, 05/11/04 11:22:57 EDT |
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Guru - Thank you for the helpful advice, after some deliberation i've settled on building a single door freon-forge with a port opposite, now I have to figure how much kaowool to buy from your most helpful website :-) referring to Daryl's post: [I use just over 7 sq ft of kaowool. It would really depend on your configuration. I think 3"s might even be better,] configuration = what factors? Would another inch of insulation save enough propane(over the lifetime) to offset the extra cost and lost interior space? |
| David S - Tuesday, 05/11/04 11:43:20 EDT |
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I've bought an old cast iron firepot and need some advice about how to make a useable forge from it, I've only used side blown forges before. It is a casting, 3/8" thick about 13"in diameter and is dished(about 3" deep) with a removeable drilled plug,3/4"thick, in the centre (It resembles the bottom of a propane tank). My problem is that it seems designed to sit on top of the forge floor rather than be bolted underneath. Has anyone encountered this design before? I've added a photo to the users gallery, the wrench in the photo is 15" tall. Thanks Bob |
| Bob G - Tuesday, 05/11/04 12:45:34 EDT |
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Bob, That is not a "fire pot" that's an old flat bottomed rivet forge without legs and tuyeer. See the photos on the Kayne and Son store forge page for what a fire pot looks like. Good fire pots are 5/8 to 3/4" (16 to 19mm) thick. Also the image labled "delamination" is common texture found in anvils made of scrap. Many anvils including all the Mousehole forge anvils were made of welded scrap. In most anvils it doesn't show but ocassionaly there was a lot of trash in the billet and it eventualy corrodes out leaving the texture you see. When old anvils fail it is from bad forge welding. I have seen anvils broken nearly through the center where the welds were bad. |
| - guru - Tuesday, 05/11/04 15:05:09 EDT |
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George, if your area has a Model A club, chances are they will have access to a mechanic who does babbiting work for the Model A engines. Other Antique Auto clubs would probably have the same access. I don't think the automotive shell bearing came into use until the mid 1930's..... |
| Ellen - Tuesday, 05/11/04 15:41:14 EDT |
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Kaowool Requirements: I have built several of the propane forges from freon cans but have used scraps and did not closely account for how much was used. To put 2 layers in a freon can forge requires about an 12" x 24" piece to cut circles for the ends. The scrap is used to make the pieces in the ends under the circles by tearing and fitting. Then about two feet by 24" is needed to fill the sides twice (with some left over). So that is three running feet more or less. Propane tank forges are larger and require a little more. I would not try to put three layers in a freon can but three will fit in a propane bottle. Besides the Kaowool and ITC-100 you need a hard refractory brick or two for the floor. In my freon can melters I fit a half of a full thickness or half thickness fire brick into the bottom for the floor. There is 1 to 2" of kaowool underneith and scraps fitted around the square to fill. In forges you want one full layer of kaowool on the sides then a half thick brick floor and then another layer of Kaowool from brick edge to brick edge. The Ron Reil plans call for standoffs supporting the brick but I have had no problem without. It does help to use scraps to fill in between the curve of the tank and the flat of the bricks. You can split the Kaowool into thin pieces for this. A pint of ITC-100 will do several small forges or one large forge and then touchups. Coating the metal surfaces that are going to get hot with ITC-213 will prevent oxidation, reduce rust and act as a primer for ITC-100 if used to glue refractory such as kaowool to metal. |
| - guru - Tuesday, 05/11/04 15:44:44 EDT |
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Babbitt site: http://www.anvilmag.com/smith/011f2.htm |
| - Mike - Tuesday, 05/11/04 16:38:43 EDT |
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David S. I think the Guru has answered your questions. 3"s of Kaowool would add to the insulating value of your forge but the biggest energy saver is the ITC, there is also the trade off in inside dimension that you mentioned. I am making and relining some forges now, I would gladly send you some pictures. I am not saying the way I do things is right or the last word. As for material prices, the store here is better than anything I have found in Canada. If nothing else buying here may help keep this site up. I would rather let the Guru answer your questions, I find he gives well thought out answers. I may know that "A" works and "B" doesn't, but not the reason why. |
| - Daryl - Tuesday, 05/11/04 17:27:16 EDT |
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hi,im an artistic blacksmith in england & have been following the iforge online stuff avidly-my up most praise to all involved- but my question is are there going to be any additional lectures in 2004? |
| matt - Tuesday, 05/11/04 18:14:38 EDT |
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Matt, We hope so, but a lot of work needs to be done first. CSI could use your help. Click on the link at the bottom of the page for more information. |
| Paw Paw - Tuesday, 05/11/04 18:29:42 EDT |
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Seems to me that using oxygen rather than air in a forge could make it significantly more efficient. Air is 80% nitrogen, all of which has to be heated to forge temperatute before it's blown out in the exhaust. You might need a very different forge design because of the smaller, hotter flame. I rather doubt you'd save enough propane to pay for the oxygen, though (air has its drawbacks, but it's hard to beat on price). By the way, I'm not sure what Havok meant by "doping," but mixing fuel and oxygen anywhere before it gets to the burner is liable to, well, wreak havoc. |
| Mike B - Tuesday, 05/11/04 19:30:32 EDT |
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Gas Forges with Air - Some years ago, I modified a Sandia naturally aspirated design by putting a blower on it. In the process, I attached the mix manifold to the chimney back and ran the feed tubes thru the chimney flue so I get some preheat on the mix. It worked well and I am still using it daily. One day, I took the cutting torch and shot some oxygen into the blower intake just for kicks. It made a hotter spot on the floor under the burner but the scale on the steel was so heavy that it looked a little like cutting slag. This was obviously not a scientific test but I suspect a 1/8 or smaller tube attached somewhere in the mix line with a regulator set on very low pressure would allow some adjustment to the flame. It's similar to playing with the mix in a carburetor. |
| - HWooldridge - Tuesday, 05/11/04 20:03:05 EDT |
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iForge demos: we have a few waiting in the wings. Currntly the problem is TIME. iForge demos take a full 10-14 hour day to prepare, demo and edit. I now spend over half my available time tending to the store and paperwork (bills, stock orders and such) in order to keep things going. I would prefer to be writing articles for anvilfire. This is also going to be a busy travel and NEWS year. We have had one issue of the news covering the Boone HammerFest and NC-ABANA at Oak Hill Ironworks. Another editon is in the works covering the West Virginia Armour-In this weekend and Paw-Paws Mini Hammer-In in NC. After that we have Camp Fenby and the ABANA Conference! Thent there is a slight gap and in October I have a big week long demo with Paw-Paw in Norris TN and then will possibly be going to SOFA Quad State the week before again. . . I also have a dozen book and video reviews waiting to be produced and posted. For over three years the anvilfire workload has been such that I have needed an office manager/secretary. The problem has been mounting daily but there is no money. So some things are not updated as often as I would like. Hopefully the new CSI initiative to become a legal non-profit entity will open some doors. Until then, I just plod along. |
| - guru - Tuesday, 05/11/04 20:36:16 EDT |
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Hwooldridge, I adjust the mixture on my atmospheric forge almost exactly the way you describe, except I add propane, not oxygen. |
| Mike B - Tuesday, 05/11/04 21:17:02 EDT |
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Mike, Yes, that's also how I put in propane on my forge - with a small line just after the blower. I was suggesting a second line with O2 to anyone who wanted to play with it. |
| - HWooldridge - Wednesday, 05/12/04 00:06:27 EDT |
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I would think you'd need a number of small burneres with a hot flame, instead of one big burner. I don't know if the oxidisation would still be a problem. This is still sort of a mental exercise for me, at the moment. Wanted to come up with a few different options before I tried building a forge myself. |
| HavokTD - Wednesday, 05/12/04 01:56:06 EDT |
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Hi Guys I have a problem can anyone help while forging some damascus (Chainsaw)I flux the job well some might say excessively but when I take it out of the forge and brush the flux off before hammering I try to brush before refluxing and returning to the forge but by then my brush (wire) is useless as it has become one big solid lump of flux and I have to stop forging to smash all the solid black flux off the wire bristles and then my billet has lost its heat how do you guys cope with this problem othe than an endless supply of brushes or an assistant who's job is just cleaning wire brushes as fast as we clog them up. any info greatfully assimilated. Derek |
| Derek - Wednesday, 05/12/04 12:38:14 EDT |
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Do you know of a source for parts, particulary bearings and an oil seal of a Champion 400 forge blower? If not, how have people been able to recondition them? maybe replace the threaded axle? and use standard bearings? Thanks, Marcus |
| Marcus Wynn - Wednesday, 05/12/04 13:37:16 EDT |
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Do you know of a source for parts, bearings, and oil seals for a Champion 400 forge blower? Thanks, Marcus |
| - Marcus Wynn - Wednesday, 05/12/04 13:41:24 EDT |
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Do you know of a source for parts for a Champion 400 forge blwer, kparticularly bearings and an oil seal? Thanks, Marcus |
| - Marcus Wynn - Wednesday, 05/12/04 13:42:46 EDT |
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Marcus-2 points. A) This is a bulleten board, not a chant. Be patient. B) Check the archives. Blower part questions come up often. |
| Nomad - Wednesday, 05/12/04 14:02:37 EDT |
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Derek, Sounds as if you are using way too much flux. My wire brushes are never clogged with anything ... well perhaps grass or other stuff if I drop them on the ground.....(g) |
| Ralph - Wednesday, 05/12/04 14:24:41 EDT |
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Parts for Champion 400 forge blower? source? |
| - Marcus Wynn - Wednesday, 05/12/04 14:30:27 EDT |
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yes Ralph I think I must be the bottom of my forge is a pool 1/4" deep I am suprised that my refractory base hasn't disolved apparently its pretty well impervious to the stuff I used foseco's pyrocrete 165,for the base and glass matt similar to kaowool and ITC's 100HT for the top of the forge the wire brush (steel bristles) has big black lumps of what look like coal stuck to them when I smash them with the hammer it pulverizes like black glass oh well I'll plod on I spose thanks for the answer mate. ATB Derek |
| Derek - Wednesday, 05/12/04 14:39:19 EDT |
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Web site's lookin good jock, its been awhile. I've been doing some sculptural work with copper wire from 18 to 8 gauge and ive met with SOME success fuzing pieces together with mapp gas torches ( one fixed, one in the hand) however it's hard to predict how the copper will behave when it already has been heated for annealing or color purposes and sometimes when it looks ready to puddle up it fizzes and begins to break down in what im guessing is a reaction having to do with oxidization. I would appreciate any helpful advice you could give me on the behavior of copper and the use of different parts of a mapp gas torch flame. Thankyou. |
| AdamSmith - Wednesday, 05/12/04 14:40:44 EDT |
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Derek, look in the FAQ's - A bunch of us got into mtrcycle chain damasus a cpl yrs ago. |
| Ron Childers - Wednesday, 05/12/04 15:03:22 EDT |
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Hi Ron I'm not having trouble welding only with brushing off the flux Borax one swipe with the wire brush and i have to put down the billet and clean of the brush I know about the motorcycle chain but here in aus you cannot get chain that doesnt have o rings almost every bike comes with them as standard now and there aint that many old bikes ere besides I find you get a finer pattern with chainsaw blades just my opinion you understand others wiser than I may think otherwise. best rgds Derek |
| Derek - Wednesday, 05/12/04 15:27:23 EDT |
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just outta curiosity, why can't you just toss an o-ringed bike chain in the fire, and burn'em out? they're only rubber, right? |
| HavokTD - Wednesday, 05/12/04 17:57:52 EDT |
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Marcus Wynn: Speaking as one Marcus to another, let me give you some advice. READ first, post second. As someone has already noted, this isn't a chat room. You've asked your question four times now, and there's almost certainly an answer in the archives if you were to do a search. Secondly, here's the answer you are looking for: There is NO source for the parts you are speaking of. I have two of those blowers myself. Your best bet is to find a second blower and hope to come up with enough parts to make one good one. Regarding the oil seal, however, it is important to note that all of these blowers leak oil to some degree, and they aren't designed to be completely filled with oil. You'll need to oil the blower every time you use it, and maybe more frequently than that if you put in long days. (the other) Marcus |
| tanix - Wednesday, 05/12/04 18:07:03 EDT |
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Dear Guru, I am looking for an innovative quench liquid, to cool large "castings" from 1300F to room temperature as fast as possible. I do not want to use water based quenchants, as the quenchant usually forms steam pockets in the deep part recesses. The steam reacts with my "casting" and forms hydrogen defects. I've tried several oil based quenchants, but the oil usually catches fire near the part as it is being lowered into the quench liquid. Aside from the fire issues, the oil usually forms soot on the roof, and a carburized coke layer on the surface of the tank. Do you have any innovative ideas for a liquid I could use? Ideally it has high heat capacity, is a good conductor of heat, and very high flash point. I am looking for a faster quench than standard oil products. I've tried a fluid bed of fine particles to cool the "casting", but dead spaces in the pockets results in slow cooling. Thanks, Steve K. |
| Steve Kenner - Wednesday, 05/12/04 18:29:47 EDT |
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Dear Guru, I am looking for an innovative quench liquid, to cool large "castings" from 1300F to room temperature as fast as possible. I do not want to use water based quenchants, as the quenchant usually forms steam pockets in the deep part recesses. The steam reacts with my "casting" and forms hydrogen defects. I've tried several oil based quenchants, but the oil usually catches fire near the part as it is being lowered into the quench liquid. Aside from the fire issues, the oil usually forms soot on the roof, and a carburized coke layer on the surface of the tank. Do you have any innovative ideas for a liquid I could use? Ideally it has high heat capacity, is a good conductor of heat, and very high flash point. I am looking for a faster quench than standard oil products. I've tried a fluid bed of fine particles to cool the "casting", but dead spaces in the pockets results in slow cooling. Thanks, Steve K. |
| Steve Kenner - Wednesday, 05/12/04 18:30:01 EDT |
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Derek, I would suggest that you cut WAY back on flux. You may find your welds are cleaner and the end result ( pattern in the billet) will have far fewer inclusions and be much nicer all around.... |
| Ralph - Wednesday, 05/12/04 18:32:26 EDT |
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Steve K. , Could you be lowering the parts too slowly into the oil? seems as if it were covered quickly you will have less likelyhood of having it flame up. of course I do not quench complex costings and usually parts I quench are less than 1 inch in thickness so it may be different. |
| Ralph - Wednesday, 05/12/04 18:37:19 EDT |
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HWooldridge, I guess part of my setup *is* like the one in a blown forge, but most of my propane goes through a fixed orifice and pulls a (hopefully) proportional amount of air through a venturi. In other words, a typical atmospheric burner. I've added a second propane line on a separate needle valve so I can bleed in extra gas without pulling in extra air. Your reference to playing with the mix in a carburetor made me think of my setup. |
| Mike B - Wednesday, 05/12/04 19:49:40 EDT |
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Derek, Most of the guys I know who make chain damascus (and cable damascus), don't wire brush the flux off. They pull the hot billet from the fire and just give it a quick flick of the wrist to sling off the excess flux. If you're using plain borax, it will be liquid enough at weldiing heat to flow right off when you swing the billet quickly. Naturally, you want to know what is going to be in the path of the flying molten flux. |
| vicopper - Wednesday, 05/12/04 21:05:57 EDT |
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All, I'll be out of town from tomorrow morning until either late Sunday evening, or Monday morning. Y'all behave while I'm gone, I don't want to have to spank anyone when I get back! (grin) |
| Paw Paw - Wednesday, 05/12/04 21:07:28 EDT |
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Oxy-Propane forge: Ideally, a forge flame should be neutral or VERY slightly off neutral. It doesn't really matter whether the flame is air/propane or oxy/propane or something else, the objective is to have the flame, and the forge atmosphere, as nearly neutral as possible to avoid excess scaling. While air/propane does have a lot of nitrogen in it, the nitrogen is inert and doesn't contribute much to scaling. It does consume some BTu's to heat it, but if yo are reaching a welding heat, then you are getting sufficient heat. The specific heat of nitrogen is very low, much lower than that of the forge body, the steel and anything else in there, so it takes very little extra fuel to heat it. If you use oxy/propane, you won't have the heat loss from heating the nitrogen, but you will have a very hefty oxygen bill. And any imbalance in the ratios will result in a VERY oxidizing flame very quickly. Furthermore, the flame temperature of oxy/propane is so high that you will face a possible problem of spot overheating of your stock and/or your forge lining. One factor that can dramatically improve the overall efficiency of a forge in moderate to heavy use is the residual heat storedin the forge body. Firebrick or kiln shelf floors and/or walls take extra time to heat up from cold, but they hold a large amount of heat that offsets the loss from the nitrogen in air. Furthermore, that residual heat heats the metal by radiatant heating and by conduction with no effect on scaling. Relying on the flame/atmosphere in a forge for all the heating means you are relying on a potentially oxidizing heat source, and one with a relatively low thermal mass. While you are transferring heat to the stock, a lot of heat is being vented along with the exhaust gases. Now THAT is wasteful. |
| vicopper - Wednesday, 05/12/04 21:20:01 EDT |
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We'll be good top soldier.How many brownie points does a tattletail get? Enjoy yourself, stop at Stuckey's. |
| - Ritch - Wednesday, 05/12/04 22:17:48 EDT |
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Ritch, Brownie points? For a tattletale? Negative 10 for every report. (grin) |
| Paw Paw - Wednesday, 05/12/04 22:31:23 EDT |
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Steve Kenner - I've been a metallurgist for 30 years, ran a in plant heat treat shop for a steel mill, worked for an industrial gas company supporting atmospheres for heat treating - I've seen a lot of different setups for quenching - when using oil, some flame is fairly common until the part or parts is fully immersed in the bath. If its a complicated shape with dead areas, you need some sort of super agitation to get flow into the pockets - commercial heat treaters use baths with venturis, pumps, etc. to get significant agitation. If you still have dead areas you'll get pockets where the material won't quench due to the quenchant going to vapor, and the vapor not being an efficient heat transfer medium. The only options I'm aware of for quenching are: oils, water, water based quenchants such as brine or with polymer additives or air. If you want to austemper then some salts, lead etc. come into play. From my viewpoint, if you're getting dead pockets, I'd suggest going to an alloy that can be quenched in still air to meet your hardness requirements - hard to gues more without detailed information on the part. |
| - Gavainh - Wednesday, 05/12/04 22:32:36 EDT |
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Thought on Quenchant This is going to be way out there, but here goes. Tin. Tin has a melting point of ~230°C and a boiling point of ~2600°C. Quench in molten tin, then oil. This sounded crazy when it ran through my head but... |
| Shack - Wednesday, 05/12/04 23:07:13 EDT |
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greetings! what a cool site. i just want to ask if i can make spring steel from a 1085 or 1095 steel by heat treatment. thanks! more power to you guys! |
| Richard - Thursday, 05/13/04 03:02:45 EDT |
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Richard; Yup, you can make fine springs out of 1085 by heat treatment. "Spring steel" as a term,is usually one of several specific alloys made especially for that purpose but for most uses the diff is almost academic. Unless you meant steel that was made in the spring time..that can be identified by having someone with severe hayfever sniff it for 35 minutes nonstop, then counting sneezes. |
| - Pete F - Thursday, 05/13/04 05:28:04 EDT |
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Steve Kenner, I too am a metallurgist, although my experience is about one tenth that of Gavainh's. In my shop we quench large forgings-20,000 lbs at times. Due to the heavy cross sections and customer requirements we have a quench tank that has many of the features Gavainh described. Our tank holds 50000 gallons and the agitation can be varied from mild to very high. For some critical parts we have developed fixtures that allow us to direct a stream of quenchent down the bore, thereby eliminating steam pockets. We use either water or polymer based quenchents because we to have found oil quenching to be hazardous. In your case my suggestion would be to find a way to get qeunchant into the "dead" areas you describe rather than look for a faster quenchant. A faster quench will not impove the properties of the dead areas because you will still get steam/vapor pockets there. One method you might try is a spray quench, This might provide you with the oportunity to completly flood the part by directing the nozzles into those normally "dead" areas. As Gavainh said, w/o more details thats the best I can do. Patrick |
| Patrick Nowak - Thursday, 05/13/04 08:34:20 EDT |
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Havok: No. Hang the chain doubled, heat it red with a torch with a fan blowing the smoke away from you and when the "O" rings crumble, brush clean with a wire brush. You need to go ahead and use it before the chain rusts and gets too stiff to work with. Derek, If you whack the billet against something hard, some of the gook should sling off. Then dip it quickly in water and more of it will pop off. Whack it on the edge for adl descaling then go to the belt grinder. |
| Ron Childers - Thursday, 05/13/04 09:09:28 EDT |
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Shack; somehow I don't think those are supposed to be minuses! Course if you are getting temps more than 2000C below absolute zero the acadamy of sweeden wants to talk with you! Thomas, still grouchy with a tooth ache |
| Thomas P - Thursday, 05/13/04 10:29:18 EDT |
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Fast Quenches: Steve, The best have answered you question now I will put in my two cents. First, metalurgical quenches rarely need to go to room temperature. They only need to get through the transition phase in the required time. After that the part can air cool. In ferrous alloys that require tempering it is best NOT to allow them to reach room temperature before tempering. This avoids thermal shock AND saves energy. If you are trying to solve porosity problems in a non-ferrous casting then you should consider chills in the mold. I've made zinc castings where the chills were cooled via a heat sink at the same time the rest of the mold was being heated to prevent misruns. Directed or spray quenches have been used since the later 1800's. It was required to make a solid tool steel anvil. Falling water from a mill sluice was used and later pumped water. Very large volumes were required. There have been ocassions when water based quenches required ice water or iced salt water to do the job. However, often the problem is volume and resupply of quenchant. Industry has solved that problem largely with refrigeration and other cooling systems. The only problem is a matter of scale. If the system is not big enough for the part then you need a bigger system. It ONLY money. . . not a technical problem. Liquid metal has been used for tempering and for quenching. Lead in particular. Salt baths are now more common. You did not say what how big (large is relative) or what alloy. I suspect that you have a badly designed casting. Parts that must be heat treated by quenching (in fact all castings) should be carefully designed to avoid big changes in thickness. Where ribs meet a surface it creats a large mass that must often be reduced from the back side with a depresion that looks like a shrink. If this is to be a finished surface then you just have to eat having a larger machining allowance. Ribs that meet are worse and it is recommend they be offset and not meet at the same place (see any book on casting design). Sometimes extra mass is used where you need a thin section and it it then the extra machined off. Sawing can be very efficient. Often a redesign is the only solution to heat treatment related problems. |
| - guru - Thursday, 05/13/04 10:47:33 EDT |
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Thomas. . . those were tildes used as an approxiation mark! Check you glasses ;) |
| - guru - Thursday, 05/13/04 10:50:35 EDT |
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I am not technically a smith, but make knives via stock-removal. My question, however, revolves around steel, and you guys seem to know what you're talking about. I have a large supply of big diamond-edge concrete cutting blades. Some are about 21" diameter, and some larger. Most are about 3/16" thick. One person told me it's probably 4130 or 4140 steel. I've experimented with it in various ways. I first cut some test strips, heated them up to non-magnetic, and quenched them in oil. They snapped pretty cleanly in the vise, with a fine grain. So I made a knife, quenched it in oil, gave it a temper, and it just didn't seem to hold an edge. So I made another one, and quenched it in water. No tempering. A new file skates across the surface with almost no bite, and I can't drill it. I cleaned up the blade and did some cutting tests, and it seems to be as good as anything I've worked with. Does anyone know more about this steel, and if I'm going to be disappointed using it for knife stock? Thanks! |
| - Mark - Thursday, 05/13/04 12:38:13 EDT |
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Mark, See our Junkyard Steel FAQ. These are the kind of parts that will be different steels from different manufacturers and may not be the same this year as last. These steels are specified by performance and bought by price. Even is somone knew EXACTLY what alloy one maker used in 2002 it would not apply to other manufacturers and years. Many things of this type are made from medium to medium high carbon steels (40 to 60 point carbon). All these steels will harden plenty hard but they may not have the toughnes you are looking for at a particular hardness. It was not an edge steel, it was specified for toughness. Using scrap steel is always a gamble. I never saw a decent hand made knife that making it from the best NEW steel would effect the price or the profit margin. But it will certainly effect the quality. |
| - guru - Thursday, 05/13/04 13:25:04 EDT |
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Saw Blades - Saws were made of premium steel when the teeth were an integral part of the blade but the trend toward carbide and other applied tip applications has allowed manufacturers to use cheaper materials in the body of the blade. This makes a better sawblade for the intended use but not as good for the scrap content to a knifemaker. |
| - HWooldridge - Thursday, 05/13/04 13:38:21 EDT |
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I apologize; the do look like tildes on "the big screen" probably not so much a glasses issue asa low res monitor issue...there goes the nobel prize... Thomas |
| Thomas P - Thursday, 05/13/04 14:07:49 EDT |
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Two observations on gas forges from a dedicated coal-fired smith: I have watched a few pro knifemakers working with their forges. All have used blown rather than venturi forges. Why? Ease of adjustment and low fuel consumption. Is your mix lean? add more gas. Rich? add more air. Not hot enough? add more of both. I've seen a very large blown forge run hot enough to melt the kaowool on about 3/4 (that's three-quarters!) of a PSI of propane. Another advantge of a blown forge is you can siphon off some of the air blast (before the gas injector) to create an air curtain across the door, dramatically reducing dragon breath. One well-known smith, when he wants a highly reducing atmosphere and doesn't want to bother with adjusting the air/gas mix, tosses a handful of wood chips in the forge every time he puts the steel back in the fire. Think outside the veturi. |
| Alan-L - Thursday, 05/13/04 15:31:25 EDT |
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Errata for the above post: advantge = advantage, veturi = venturi. PROOF, then post... |
| Alan-L - Thursday, 05/13/04 15:33:26 EDT |
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Would old truck parts have any use? I have alot laying around and old oil barrels? Thanks |
| - Bucky Bo - Thursday, 05/13/04 15:57:47 EDT |
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Bucky Bo: Old truck parts and oil barrels have lots of uses, what did you have in mind? Fixing trucks and holding oil come to mind. ;) Springs and suspention bars tend to be good high carbon steel for tools, axles are good for hammers, small anvils, and other stuff, the aluminum parts can be melted and cast, and I'm sure uses could be found for lots of other parts. Cast iron is probably the least useful steel in a truck, but even that can be useful if you're into the right stuff (the cast iron can be used in smelting to make higher carbon content). Barrels can be used for quench tanks, anvil stands, charcoal retorts, forges, garbage cans, etc. Good luck making use of your junk. :) |
| AwP - Thursday, 05/13/04 16:18:18 EDT |
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Red Hot I was wondering if all materials glow the same color at the same temp. Is cherry red steel the same temp as cherry red brass and the same as cherry red fire brick etc? |
| Shack - Thursday, 05/13/04 16:33:50 EDT |
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Yes, something to do with black body radiation I think. But there should be a better (and more accurate?) explanation along soon! |
| Nigel - Thursday, 05/13/04 17:15:09 EDT |
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THOMAS: Try extra strength Anbesol. Good stuff fer yer sore toofie. It's benzocaine, the same stuff the dentist smears on your gums before he hits you with the needle. Works fer me. I feel yo' pain, Brother. |
| 3dogs - Thursday, 05/13/04 18:25:16 EDT |
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Hi all, Just wanted to introduce myself. Hobby smith, small work area, but I have a ton of fun doing it. Enjoy this forum and the info that's availaible here, so I joined CSI to help support it. Thanks! Aaron |
| AaronHoldg - Thursday, 05/13/04 19:02:56 EDT |
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Bucky Bo, As AWP noted there are many good bits in old trucks. As for old drums, do you know what they held? If not, the probability is that there are chemical residues that are lurking inside. Tread with care, lest methlyleethyledeath bite you, or your loved ones. I would always caution persons seeking to reuse drums to ONLY use those that have the original content labels still readable. By the way, plastic drums are often the ones with the nastiest previous contents. Good luck |
| ptree - Thursday, 05/13/04 19:26:14 EDT |
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AaronHoldg, Welcome to the generous brotherhood of smiths that make this site possible. |
| ptree - Thursday, 05/13/04 19:28:45 EDT |
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Welcome Aaron, That blue lettering on your name looks great doesn't it! And now you can check out the members forum and see whats been going on, and don't forget to post there too and introduce yourself, etc. |
| JimG - Thursday, 05/13/04 19:57:56 EDT |
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I found an anvil made by BNC in a junk shop. It is a cast anvil with a weight of 198 lb.s. It has a 1 inch hardy hole, but no punch hole. I would like to find out some information about the anvil. |
| head - Thursday, 05/13/04 20:19:49 EDT |
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My question is about Hossfeld Benders: The first hole back from the main (center pivot) pin is smaller than all the others. On some benders it is tapped out to 3/8" NC; on some benders it is about 7/16" thru. What's this small hole used for? |
| - Jim C. - Thursday, 05/13/04 20:29:19 EDT |
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Hi, my question to you is, what is the process to make new galv. sheet iron look rusty. I have thought about muratic acid in a diluted form,or just plain old vinegar.What is the fastest way to make this process happen? Any info will be very helpful. thanks and have a great day. |
| bud - Thursday, 05/13/04 20:42:04 EDT |
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Galvanized to Rust: Bud, the point of the galvanizing is to prevent rust. When the zinc coating oxidizes it turns grey then white or if oily black. To make rusty you would have to strip the galvanizing. It would take a LOT of acid. The best thing to do is by new clean sheet. |
| - guru - Thursday, 05/13/04 20:49:34 EDT |
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I have just had built an ornate table stand using flat bar steel. I would like to permanently blacken it to look like the finish on wrought iron steel gates. I'd appreciate your advice. Thankyou Robert |
| Robert - Thursday, 05/13/04 21:00:09 EDT |
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Hossfeld Hole- Jim one of the pins has a smaller tab on the curved over end which you insert into that hole for eye bending operations on very thin stock. I'm sure it has other uses also but I can't check my manual as I loaned it to somebody. Thanks for reminding me to ask for it back! Welcome, AaronHoldg I hope lots of folks folow your example. |
| SGensh - Thursday, 05/13/04 21:01:54 EDT |
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Hossfeld Bender: SOMEWHERE in all my junk I have a Hossfeld Catalog which shows all the die setups. Some bend around the center, other are used like press dies. OK Looked at mine. . That hole is for the circular gauge ring to bolt to. It bolts on there and beyond the last hole. |
| - guru - Thursday, 05/13/04 21:05:21 EDT |
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VICopper I thought your explanation of heat in gas forges was both accurate and well-put. Just one thing to quibble with. I don't think it's really accurate to compare the specific heat of the nitrogen to that of the forge body. The forge body gets hot and stays hot, but the nitrogen keeps changing. I think a more valid question would be how much heat is conducted through the forge walls and lost to the atmosphere versus how much comes out the exhaust. Not exactly scientific, but I can get my hand a lot closer to the side of my forge than I can to the open door. Of course there's radiation too, but no nitrogen could mean an 80% smaller vent area, and maybe correspondingly less radiation loss. I still agree totally with your conclusion that using oxygen would cost much more, not less, though. Of course, I'm slow to catch on to things sometimes. After years of reading your posts, I've only just realized that the second part of your nickname may not relate only to your skill at working non-ferrous metal. |
| Mike B - Thursday, 05/13/04 21:17:54 EDT |
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I’m in my second year of smithing, and have made a number of the projects from the iForge, and I’m quite fond of the roses. I have made two using the pre made petals and riveting them in place. But I find myself making far more using the “Russian rose” method. I upset the rod and use a monkey tool to square the bulb before drawing out the stock for the petals; the ones that don’t end up in scrap heap are gorges! So hears my question, have you or another smith made one out of Damascus using this method? I love the look of Damascus and have made a number of knives and swords using different patterns, and think it would pout a beautiful twist on a traditional peace. I would be grateful for your any feedback you might have. |
| Kevin Brown - Thursday, 05/13/04 21:34:24 EDT |
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Welcome Aaron, glad to have you aboard. Anyone else ready to join CSI and help keep anvilfire.com alive? |
| Nomad - Thursday, 05/13/04 21:58:19 EDT |
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I would like to know what are your alturnitives to a anvil?I'm just a hobbyist and dont want to have to buy an exspensive anvil.Also what is a good first project?thanks for all the help |
| - John - Thursday, 05/13/04 22:04:41 EDT |
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Mike B, I'll agree with you on all counts. True, the nitrogen form th eair is continually being lost and replaced, but the specific heat is so low that I doubt that the loss is overwhelming. Definitely significant, but cheaper than O2. We agree. As for loss through conduction of the forge walls, that is a function of the R value of the insulation and its thickness. Probably considerably less than that lost to "dragon's breath", though I have no hard facts to back that up. Having a smaller vent area would mean less heat loss through venting, but it would also mean fighting harder to get stock through the access area/vent. If you can put stuff in the forge and close the door, then less vent area would probably make a pretty noticeable difference. Enough to pay for the oxygen? I doubt it, but no dragon breath would be a real plus. However, you still have to have some vent area, and the vent gases might be really, really hot if you use oxy/propane. Might be a break-even situation. I think the real goal should be to get the burner(s) adjusted as perfectly as possible so that the atmosphere is right and the exhaust velocity/volume is as low as is consistent with developing the required heat. Again, more and better insulation will make a big difference. I have also noticed that having a few chunks of broken kiln shelf or firebrick in the forge makes for a more even heat and a less oxidizing atmosphere. I suspect the the additional surface area of radiant objects is consuming more excess oxygen and re-radiating more heat to the work. I have come to believe that having a significantly turbulent flow through the forge is a good objective rather than a negative. Just like a slow blast in a solid-fuel fire will give a less dirty fire. Lastly, you surmise correctly regarding my online cognomen. I am a law enforcement officer in the Virgin Islands when I'm not beating iron or pontificating about abstruse subjects. The former is more profitable, the latter two are more rewarding in other ways. (grin) |
| vicopper - Thursday, 05/13/04 22:06:12 EDT |
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Oxygen & Forges - In my misspent 30 years part of it was as an engineer in Industrial gases + 1 disastrous year as a consultant with a reheat furnace manufacturer - learned a lot, but not a lot of fun. With Airco, I did a lot of support of oxygen enhanced combustion - sometimes it was tweaking an existing system with up to 10% O2 bled into the total combustion air. Other times, it was using an oxy-fuel burner to assist the heating process. Things that happen with increased oxygen - 1. Flame temperature increases, gas use drops, more NOX is created. Ususally the decrease in gas use would not pay for the cost of the oxygen. (and that's at a cost of $.20/100 cubic feet a fairly typical cost at the time for a large industrial user.) When coupled with a desired production increase through existing equipment, it often paid for itself. 2. Oxy-fuel burners were usually associated with melting projects when they were associated with metals - a typical application is to place one or more in the cold spots of an eletric arc furnace to help melt the charge - basically think of an oxy-natural gas torch with a tip opening of 2" to 4" - impressive in use. Again - much higher flame temperature - NOX generation may be a problem, higher productivity & natural gas cost versus electricity costs were another factor in the equation. The more odd-ball applications were things like putting an oxy-waste fuel burner in as an assist to a cement kiln - again, more productivity, one positive aspect was that you could use contaminated waste oils - temperature and dwell time in a cement kiln was high enough to break down nasty organic chemicals such as dry cleaning fluids to the constituents of oxygen, carbon dioxide, water vapor, nitrogen, etc. (Note the only time I ran a trial on this was using waste oils from restaurants.) Good chemistry & good use but feedstocks were often erratic, and once someone tied in a feedstock they could see prices go from negative(paid to take and get rid of it) to positive. Sorry if I've rambled a bit much - just general experience with oxy-fuel. |
| - Gavainh - Thursday, 05/13/04 22:38:46 EDT |
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Hossfeld answers - thanks for the help. |
| - Jim C. - Thursday, 05/13/04 22:59:55 EDT |
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Ten Hammers, I just broke down and bought one of the top of the line Jackson autodark helmets you mentioned on Sunday. $309. Actually, my wife was along and approved the purchase. Recently bought a plasma cutter and needed something a smidge darker than #5. With it set on the "torch" setting, it works well on the plasma with my sensitive eyes. I use shade 12 for welding unless it's low amp Tig. The best autodark helmets have 4 light sensors. Not one or two. Less chance of not darkening I'm told. I think it was worth the $309. No matter how hard I try, occasionally I flash myself in the process of setting up the torch or flipping the old manual helmet down. After using the new helmet for 10 minutes, I was not lifting the helmet anymore. With the big view area and as light as it gets when not welding, no need to lift up the helmet even when welding under the truck inside the garage. It's supposed to go dark in 1/25,000 second, but I just set up my torch position, strike/start the arc with my eyes closed and open my eyes to a darkened helmet. No lost weld position and no eye flash. I am gonna seriously kick myself in the butt the first time I drop it on the floor though. I don't know what I'd do without my vision, and the new helmet with the eyes closed at arc start seems like it will help my chances to see longer into old age. I know too many weldors with the center of their vision burned out. I've been watching and using others autodark helmets for quite some time and I think they are now where they need to be. Personal opinion. Now to add supplied clean air to it for best lung protection and away we go. Oxypropane flame will be far more expensive than air/propane. The amount of heat the nitrogen takes out is considerable though. Oxygen should only be used with nozzle mix burners for safety reasons. An Oxypropane flame with proper mixing can be set to reducing and avoid the scale issue. Getting the proper mixing with the right ratio is the key. Not easy to do in a home built venturi burner. |
| - Tony - Thursday, 05/13/04 23:22:22 EDT |
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Last Note on Oxy Assist - Or lack of: Since the 1700's it has been a well known fact that fuel efficiency can increased tremondously by scavaging lost heat. Preheating the intake air and fuel with the exhust gas save a LOT of BTU that goes into heating them from room temperature (or less). This is called a recupritive forge or furnace. Note that you NEVER preheat the fuel air mix! AND preheating the fuel requires some careful engineering but is done in some cases. But preheating the air is relatively easy and can be done on solid, liquid and gas fuel furnaces. A thin walled stainless steel heat exchanger can easily raise the intake air to 50% of the exhust temperature. Increasing the intake air temperature can raise the furnace temperature by 100's of degrees F. This can be the difference in achieving welding heat or not. Although the heat exchanger is an additional cost it is a ONE TIME cost. Good recupritive design often uses a shell outside the furnace to pick up heat AND to help cool the furnace shell. Note that one must be careful NOT to recirculate exhust fumes into the burner. This creates copious quantities of carbon monoxide. Damascus Flowers: Kevin, Many pieces of art are produced in laminated steels. For artistic purposes pure nickle is often used with mild steel or pure iron. This produces the maximum contrast. High carbon steels are not needed since the pieces are art, not blades. There are some fine examples in the Dona Meilach book, Decorative and Sculptural Ironwork. See our book review page. |
| - guru - Friday, 05/14/04 00:57:38 EDT |
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The ARMOUR-IN: I will be on the road tomarrow (Friday) and attending the WV Armour-In this weekend. Was very interesting last year and will report more in the NEWS next week. See ya'll on the flip side. |
| - guru - Friday, 05/14/04 01:01:49 EDT |
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AaronHoldg, Welcome to the CSI family. I hope you learn as much from being a part of this group as I have over these past years. John, Any heavy chunk of steel with a flat surface will work as an anvil. Most of my work is done in about a 4"X4" square anyway. All of those other anvil features are just icing on the cake! Scrounge around at your local scrap yard. I'm sure they'll have something that will work for you on a budget. As for 1st projects, I always recommend iForge demo #132 (EZ tongs). It touches on many of the basic skills and leaves you with something useful for your next project. To develop a feel for how the metal moves, I lean toward simple S-hooks and leaves. As you get good at those, you can begin to combine the two into more ornate hooks and even candle holders and such. The keys are willingness, practice and practice (intentional duplication). I highly recommend reading and following the shop safety section on this site. Hot metal is not very forgiving if you get careless. Have fun, and be safe! Eric |
| eander4 - Friday, 05/14/04 01:35:43 EDT |
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Blown forges and fuel consumption: Adding a blower doesn't really affect fuel consumption by all that much. Those forges running on 3/4psi probably have large gas orifices. Some of the large burner designs I've seen just have an open-ended 1/8" or even 1/4" pipe. So, yes, they run on less pressure, but that pressure is dumping a whole lot more fuel. When I was experimenting with a normal venturi burner, I added a blower without changing the .035 mig tip orifice. I was able to reduce the pressure and keep the same forging heat, but it wasn't all that dramatic, 7psi down to 5. No real calculations, but I expect the added electrical costs of the blower offset any propane savings. One big benefit from using a blown burner with a large orifice is safety. You no longer need to have a 35 psi supply available. If that line breaks, you're filling up your shop pretty quickly with propane. |
| - MarcG - Friday, 05/14/04 08:34:20 EDT |
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Well, I’ve finally caught up on all of the postings while I was away at the Longship Company expedition to the 39th International Congress on Medieval Studies (http://www.wmich.edu/medieval/congress/) at Kalamazoo. Well worth the effort. I bought many books (more books than I had money but the crew provides generous loan terms; of course, if you’re late on a payment, it can get very painful… ;-) mostly on Anglo-Saxon and Viking finds and early medieval technology. I spent some time with AVISTA, the techies of medieval scholarship. (http://www.avista.org/). It is nice to see some folks working on the nuts-and-bolts of daily life. I asked my traditional question on “anvil stones” as to the actual type of rock being used. Nobody ever seems to know; granite, basalt, quartzite, Styrofoam (r)? I did a Google search when I got back, and all I pulled up was some large rock formations and myself on the BBs . Another elusive mystery to be solved. I still have some e-mail to respond to, but should square that away this weekend. Sunny and warm on the banks of the Potomac. Visit your National Parks: www.nps.gov Go viking: www.longshipco.org |
| Bruce Blackistone (Atli) - Friday, 05/14/04 10:07:50 EDT |
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Something wrong with the setup of my MS Word program line spacing. Looks awkward when cut and pasted. |
| Bruce Blackistone (Atli) - Friday, 05/14/04 10:10:07 EDT |
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One downside to blown forges is they are easier to blow yourself up with. If the forge is hot and the fan dies while the gas is on, bad things start to happen. A little common sense in lighting helps too, i.e. always turn on the air first. John's Anvil question: Remember not to beat on cast iron, but other than that if it's a big hunk of steel, try it. |
| Alan-L - Friday, 05/14/04 10:52:49 EDT |
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Thanks Ralph, Ron, Vicopper, For your answers Re: flux removal I dont have a problem with inclusions or cold shuts the only problem is,I wet forge and if I dont remove some of the flux as you all are probably aware when I strike the flux explodes and goes everywhere. I am starting to look like spotty muldoon (a cartoon Character) as when I started off smithing a while back I made the mistake of wearing a nylon shirt under my apron and we all know how fast flux melts through nylon and skin so I had to find an alternative to the steel brush I might try tapping the billet on the side of my "anvil" as was suggested again thanks all. best rgds |
| Derek - Friday, 05/14/04 11:25:09 EDT |
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John; there are *NO* alternatives to an anvil---BUT, an anvil is a hunk of metal (or sometimes stone) that you can hit hot metal on and there are a *lot* of alternatives to the london pattern anvils that are costly. (though the russial ones from Harbour Freight can be found fairly inexpensively---*not* the cast iron chineses anvil shaped objects they also sell...) Take a look at what the japanese sword smiths forge on---a big rectangular hunk of metal---and their work is generally considered ok... Visit with the neo-tribals and look at their improvised anvils---some cast in a bucket of concrete to add mass. I've done patternwelded billets on a chunk of RR rail and had a broken train copuler that made a great light anvil---all free BTW, asking a RR crew for scraps and explaining that you want to forge with them often works wonders...much safer than scrounging around RR tracks these days!. Alan-L; I've had my blown forge lose power lots of time, all that happens is that the dragon's breath becomes visible yellow propane flame, no biggie just turn the power back on or turn the propane off. How are you going to blow your self up with it? Atli, I guess you are OK until the crew wants to go water skiing...\ Thomas |
| Thomas P - Friday, 05/14/04 11:28:33 EDT |
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Hi guys One quick question I was checking out "Bill Epps" excellent iforge demo on Tong's and my query is I'm in Australia and I dont have a clue what "sucker rod" is what else would be an acceptable alternative to make Tong's out of. ATB |
| Derek - Friday, 05/14/04 11:44:01 EDT |
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Derek, "Sucker Rod" is the shaft that operates the piston in an oil well pump, I believe. It is medium carbon steel similar to 1040 as far as I know. Alternate materials for tongs include, but are not limited to, mild steel, car/truck axles, torsion rods, old sign frame rods, etc. For most tong designs, mild steel, called A-36 here inthe US, is just fine. Preferrable actually, since tongs may get hot and then quenched, which might fracture higher carbon steels. If you are making very lightweight tongs, then a medium carbon steel would be better as it would be less likely to deform. For simple mild steel tongs, I use the Dempsey Twist method most often. I start with 3/8 by 3/4 for medium-heavy tongs and 5/16 by 5/8 for light tongs. If I was using a powerhammer for the drawing, then heavier stock would be an option. For drawing by hand, I like to startwith stock that doesn't require so much work. Welding on reins from 3/8 or 1/2" round stock also saves a lot of hammer work. |
| vicopper - Friday, 05/14/04 13:50:12 EDT |
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Vicopper thank's for the feedback looks like I be visiting a wreckers for some torsion bars, I tried mild steel but the jaws kept bending open in use,like some cheap oriental spanners. sorry the thanks is a bit slow comming just had a power failure for a couple of hrs. bst rgds |
| Derek - Friday, 05/14/04 17:37:35 EDT |
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Where would I find some info on restoring a blower? I have aquired a "Canadian forge and blower co" blower that is seized up, and I would love any info on fixing it up. |
| SHERK - Friday, 05/14/04 19:08:23 EDT |
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Sherk, for the most part you are on your own. Many of these older blowers, while they look the same on the outside are different on the inside, even from run to run within a plant. There are no replacement parts made currently. Best advise I can offer is to disassemble CAREFULLY and slowly so you can save as much as possible. Hopefully it is just gunked up and not truely seized. |
| Ralph - Friday, 05/14/04 19:16:54 EDT |
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Derek, Tongs: if you are having then spread out in use they are made wrong for the stock you are using them on. A correctly fitted pair of tongs take almost no force to hold the stock. When you are holding stock that is too big or wrong shaped for the tongs being used is when you get mis-formed tongs as well as causing injuries to yourself or others due to flying hot metal. |
| Ralph - Friday, 05/14/04 19:19:13 EDT |
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What would be the best type of protectant for metal that will be outside? I've heard that paste wax alone won't quite handle the weather that great. I did ask someone a little while ago and remember them mentioning beeswax plus about two more things to mix together but I didn't write it down at the time and now I can't remeber just what it was that they used. Any suggestions? Thanks. |
| Chad Anderson - Friday, 05/14/04 20:27:03 EDT |
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Chad, Where I live, on an island, nothing less than cold galvanizing followed by primer then two or more coats of good automotive paint will last more than a year. The salt air and high UV levels are hard on any finish. In a more benign climate, proper painting will last for as much as twenty years or more. Wax, or homemade varnishes such as the beeswax, linseed oil and turpentine finish that is popular, may only last a few weeks. They may also last a few months if they are in an are that is not exposed to the elements too severely. Those finishes are, however, better used for interior work only. I recommend you use the 90% zinc cold galvanizing after sandblasting or pickling the metal to remove all scale. Then a coat of red oxide primer, then two coats (minimum) of name brand acrylic enamel or lacquer designed for automotive use. If everything is clean and scale-free, this finish should last a couple of decades with only minor touch-up. If it becomes chipped or abraded, then it will begin to deteriorate unless itis touched-up promptly. |
| vicopper - Friday, 05/14/04 20:42:34 EDT |
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I find that Rust-oleum Crystal Clear works quite well on work that will be left out in the weather. It will wear off after a period of time; reapply as needed. |
| Limbo - Friday, 05/14/04 20:53:02 EDT |
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Comment on Quenching: Martensite, the stuff you are trying to form when you quench steel, begins to form around 700F. You usually have to quench quickly to get there or another microstructure will form and you will not get the part hardened. Between about 700F and what is called the Mf temperturature (Martensite finish) the martensite forms. The Mf temperature can be be anywhere from room temperature to -100F depending on the exact chemistry of the steel. If you do not know what kind of steel you have, it is difficult to know when to stop quenching. The safest bet for full hardening to to cool it in the quench down to room temperature. However, there are times when you can pull the part out of the quench hot and let it self-temper but youmay not get full hardness when you do this. |