Blacksmithing and Metalworking Q&A : anvilfire Guru page : August 16

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This is an archive of posts from August 16 - 24, 2007 on the Guru's Den

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LG serial Numbers: Dimag, on all LG's that I have seen there is a machined flat on the side of the frame (I cannot remember which) and the numbers are stamped in. The flat is about 2" x 4" and about mid-way up. The stamping is quite shallow and a coat of paint or two especially over dirt will make it hard to find. IF someone has mounted an after market motor setup it is possible to have covered the numbers but I think they are a little low for that.

- guru - Thursday, 08/16/07 07:22:45 EDT

Blower Overrun: That is about right for a blower in good condition but I have seen some roll on for longer. The critical thing is that the gears are quiet. These type gear trains do not need slingers as the oil sticks to the gears and is carried up from one to the other. Some may sling off the high speed end on its own. Cranking speed is from 0 to about 40 RPM resulting in a max of about 1200 RPM on the fan.

- guru - Thursday, 08/16/07 07:26:57 EDT

Silence: Troy, When asked about a specific product that we do not know there is nothing to say. I know the fellow makes a nice line of forges from what I have seen but I have no experience with them or have seen them in operation. They are pretty much a typical light duty (compared to industrial duty) blacksmiths forge in the class of NC, Chile (another advertiser)and Forge Master (sold by the Kaynes) and a little heavier than others.

"Welding Heat" is also a bad term. In mild steel and wrought welding heat is hundreds of degrees F hotter than for high carbon steels. Welds in these also requires better atmosphere control. Small welds are often impossible in a gas forge that will crank out tons of high carbon laminated steel billet. Most gas forges will do this even if they do not reach "welding heat" for wrought iron OR have a well enough balanced atmosphere to do small welds.

- guru - Thursday, 08/16/07 07:38:09 EDT

need info on blueing, (new animal traps)

chach - Thursday, 08/16/07 08:26:28 EDT

chach, Try birchwoodcasey.com

Frank Turley - Thursday, 08/16/07 09:24:43 EDT

Brownells.com is another source for both hot and cold bluing supplies.

Bernard Tappel - Thursday, 08/16/07 10:07:22 EDT

Troy, what he said "I can only offer that I have never used, or seen that brand and know nothing of them." Both of my propane forges are ones that I built at SOFA gas forge building workshops: one blown, one aspirated.

My favorite blower does 3 full revolutions after I let go---gives time to switch out tooling or change hammers/tongs, wipe sweat or get a drink---very handy!
Thomas

Thomas P - Thursday, 08/16/07 11:01:14 EDT

Chach,

For what you need, an inexpensive cold blue would do fine. These are wipe-on, instant-action chemicals that give a blue-black color. Gun stores often carry them.

Matt B - Thursday, 08/16/07 12:16:30 EDT

Can someone here tell me how the heck to find a spring shop in my area? I've tried the Yellow Pages (paper and online) and all kinds of Internet searches, all to no avail. Either I'm looking in the wrong categories, or the local spring shops don't advertise. (It's also conceivable to me that there *are* no local spring shops. There isn't a lot of industry here on the banks of the Potomac.)

The next logical step would seem to be to find someone in my area who buys custom springs, and ask him where he gets them. I'm just not sure who that someone might be. I've tried a couple of places that work on truck suspensions, but they said they use stock springs. Any suggestions? What sort of businesses would be likely custom spring buyers?

Matt B - Thursday, 08/16/07 14:24:54 EDT

Matt, what town/state do you live in?

Thomas

Thomas P - Thursday, 08/16/07 14:59:38 EDT

Thomas,

I live in Northern Virginia, just outside D.C. But I'm not expecting anyone to give me a name. (Of course if anyone has a name handy, that's great!) I don't mind doing the leg work; I just need some leads.

Matt B - Thursday, 08/16/07 15:12:46 EDT

Matt B,

I also live in the DC area and built a treadle hammer about 15 years ago using the original ABANA plans. For this hammer I had leaf springs made at a local shop...regrettably, I have no idea what the name was. However, I just checked the Northern VA yellow pages and I find a number of entries under springs. Most promising would appear to be Chantilly Spring Works at 703-430-7766 or Virginia Spring and Alignment Service at 703-237-3452.

Mike Joy - Thursday, 08/16/07 15:38:59 EDT

Well that's embarrassing. I must be an idiot. But thanks Mike. I'll talk to them. Chantilly's not far from work.

Matt B - Thursday, 08/16/07 15:48:47 EDT

Matt,

Are you a member of the Blacksmith's Guild of the Potomac? We've been successful at getting heavy truck spring drops donated from a local spring shop (I'm not sure which one), and most members probably wound up with a few. If that's what you're looking for and you can make to our meeting tomorrow evening (7:30 at Gulf Branch Nature Center in Arlington), I'll bring a few chunks.

Mike BR - Thursday, 08/16/07 17:01:04 EDT

Rereading my post, I should make sure it's clear -- you're welcome to come to a BGOP meeting whether you're a member or not.

Mike BR - Thursday, 08/16/07 17:20:43 EDT

Mike,

I'm not a member, but I'm aware of you guys and even bought a blower from one of you. I've been meaning to get to a meeting. I'll try to make it tomorrow. I'm not looking for springs for stock, though; I'm wondering about having one fabbed for the linkage on a JYH. ON THE OTHER HAND, you can never have too much steel. :)

Matt B - Thursday, 08/16/07 18:08:14 EDT

Matt I spent 6 years in McLean VA---back when it was still partially rural and I used to ride my bike into town to go to the library...returned a few years ago; only place I found that I could remember was the Three Little Pigs BBQ still in the same place 40 or so years later...

Thomas

Thomas P - Thursday, 08/16/07 18:15:22 EDT

Yep. If I had my druthers we'd be in the Shenandoah Valley, but work keeps me here.

Matt B - Thursday, 08/16/07 18:55:33 EDT

Matt,

That's a good attitude to bring tomorrow -- we'll have a trailer load of shop-move leftovers to pick over. I just threw two of the spring drops in the car so I won't forget them.

I finally made it to Three Little Pigs last month. I think I share Thomas's taste in BBQ (which, if I remember his last post on the subject, does not particularly include that restaurant's style).

Mike BR - Thursday, 08/16/07 18:56:05 EDT

Ooops -- I meant the attitude in Matt's 18:08 post.

Mike BR - Thursday, 08/16/07 18:57:33 EDT

Matt B,
Unless you are doing something wild, you really don't need a fabbed spring for a hammer like the rusty. Almost every truck spring shop has 25/16" wide spring stock, with a center pivot hole. These can be used with the factory arch, but most spring shops can de arch the spring. That center hole is usefull, as you can use that to center and retain the spring on the pivot. A bi-metal blade on the slow speed in the 4" x 6" bandsaws will cut the springs to lenght just fine, and if a hole needs to be drilled, a standard good quality HSS twist drill at 90 rpm and lots of steady feed will drill it dry. The drilling was a tip from my spring shop, 4th generation spring guys.

ptree - Thursday, 08/16/07 18:58:04 EDT

Hello there folks, I was wondering if you knew of any thick primers or paints that might hide grind marks without using bondo. My helper got a little sloppy with the grinding and the client is upset. I thought as long as the paint is not gloss it should be ok. What do you think?
Thanks

Matt - Thursday, 08/16/07 19:42:00 EDT

Miles, Shame on you! a Cannady Otto Royal is the far superior blower. It does not get tired, only wants some oil, and won't rat you out to your wife:)

Seriously, I have one and find it superior to any other I have tried. I know where two are laying and am scheming to buy them. I need a replacement for the demo trailer when the sheet metal Buffalo rivet forge blower packs it in. Mine coasts about 2 turns+

I personally like ATF for my blowers. Good low temp pour point, excellent antiwear package, and easy to find anywhere, cheap.

ptree - Thursday, 08/16/07 19:59:35 EDT

Matt, there are a number of sandable primers in the auto paint industry that are used to cover swirl marks etc. But thats not a great quality idea.

ptree - Thursday, 08/16/07 20:01:18 EDT

Thumper-- un-understand your question Re: "overrun." I'd pour some oil down its gullet every time I use if I were you. You can find more oil a lot easier than you will ever find another Canedy-Otto blower.

Miles Undercut - Thursday, 08/16/07 20:17:58 EDT

Thumper, Jock-- Sorry, had not yet seen Jock's answer to your question re: overruns when I posted the above.

Miles Undercut - Thursday, 08/16/07 20:32:16 EDT

Jeff,

I wasn't thinking Rusty style; I was thinking Dupont style linkage using a bow spring, like the SA-JYH and a couple others on the power hammer page. I wouldn't need it de-arched; I'd need *more* arch. But I haven't entirely ruled out a Rusty style hammer yet. It'd be a lot simpler to build, and simple is good.

Mike BR, I'll be at the meeting tomorrow night.

Matt B - Thursday, 08/16/07 21:17:59 EDT

Grinding Marks: I always reworked welds in the forge rather than using a grinder because no matter what you do ground surfaces look different than the rest of the finish be it forged or mill finished. If you DO grind then if must be with a wheel that leaves no obvious marks such as a flap wheel. THEN you need to heat the area to put on some scale to match the surrounding area. This can be done in the field with a torch.

When smiths finish work with a grinder or file they should plan on finishing EVERYTHING the same way. Many old railings and gate jobs were done this way until they looked like a piece of whitesmith work. Then they were often lightly oiled and left to rust. . The National Cathedral has numerous pieces finished this way that have been poorly maintained.

To change the surface texture of a paint job is easiest when you want smooth. When you want texture then you have to come up with a system that creates the texture. Lacquers can be put on very dry and dusty building up a scale like texture then finished with a sealing coat to hold them all together. You can also get fillers to creat texture. This is one reason I recommend lacquers over enamels. Hard lacquers can be repaired and the finish changed locally as necessary. But it requires skill and practice. It is AN ART. But as I have often noted, the finish is part of THE ART and many smiths fluff over it, under bid it or just don't do it.

- guru - Thursday, 08/16/07 22:58:05 EDT

Guru(s),
I have just bought a little 65lbs anvil and I'd like to find out what I've got. Can anyone tell me about "Attwoods Best" anvils? I'm told that it is forged, not cast, and was likely made here in Australia.
Thanks.

Craig - Friday, 08/17/07 02:42:23 EDT

Grinding Marks,

If they'll somewhat ugly but not extremely deep I would try an automotive high filling type primer that is made for covering up sanding and grinding marks on autobody work. It's most likely a 2 part epoxy type filler so you need to make sure to use a proper resperator with filters designed for automotive paint. Trust me you don't want to use a dust mask, don't ask why I know this.

juterbock - Friday, 08/17/07 07:45:12 EDT

I think it was Miles who posted about tesseracts, a cube existing in hyperspace. I spoke with a friend of mine involved in physics. The original post was real confusing because you used vague terms and improper terminology. A square cubed, the ORTHOGONALLY reproduced (you said diagonally), then doubled (you said "twin that" which confused us). The easiest way to have explained it was to say take a wire cube and present that within a cube attached by the corner points. My frined gave me some research materials and we came up with this:

http://greatnippulini.com/tesseract.jpg
http://greatnippulini.com/tesseract2.jpg
http://greatnippulini.com/tesseract3.jpg

Hope this clears things up. Plus, it's a nice work of art and representation of physics at work.

And yes, guru, tesserae is a form of art using broken tiles.

- Nippulini - Friday, 08/17/07 13:23:24 EDT

Since the Great Nippullini seems to be to bashful to tell us himself, I just wanted everyone to know that he did indeed set a new world record-
70.58 lbs of anvils, lifted with his nipple piercings, live on the radio as well.

My Nimba weighs 260lbs- he will have to practice a bit more before I can hire him to move it from place to place, but he can still lift a whole lot more than I can...

- ries - Friday, 08/17/07 14:01:18 EDT

Aww garsh fellas... thanks.. heh heh. My true goal is to lift 100 lbs. My Wilkinson is a 0-3-8 plus 8, a perfect hundred. I always wondered what the extra 8 hanging under the weight markings was for until I actually put it on a scale.

- Nippulini - Friday, 08/17/07 14:17:26 EDT

Craig: ATTWOOD would likely be English. Listed on Anvils in America on page 72. Not much said about them. Are there stone weight stamps, such as 0 2 4? The ones he documented say ATTWOOD over WARRANTED over the stone weight. Likely same manufacturer. BEST may indicate they used only high quality scrap wrought iron in the body.

- Ken Scharabok - Friday, 08/17/07 16:29:39 EDT

Different steels with different carbon content have different welding heat. correct? So, if your making a pattern welded blade and have two different steels, say; 1085 and 1020. Who do you satisfy both steels different welding temps, without burning one and not getting the other one hot enough?

THANKS!!

- steven M. - Friday, 08/17/07 16:31:33 EDT

TGN-- "vague terms... improper terminology" !!! Fie, sir, I say fie! And pish tosh. We did indeed make wire cubes, back in 12th grade math, and connected them at the corresponding corners. But the connected corners were all on cubes of the same size, and each pair thus connected-- was then twinned. Your assemblage is pretty but it ain't a representation of something raised to the fourth power to my way of thinking, because the something you started with-- A, the line, squared to make a square, cubed to make a cube, has now changed size. The word as we used it back then was tesserac. The dictionary says tessera. Sorry you are confused.

Miles Undercut - Friday, 08/17/07 16:41:54 EDT

Ken,
It only has 65 stamped on the opposite side to the maker's stamp. It's only small but certainly seems to spit all of the shock back into the hammer when I give it a tap, unlike the crappy piece of rail I'm used to!
Cheers

Craig - Friday, 08/17/07 16:46:18 EDT

Thomas P,

When I posted that info about rail anchors, you had a couple questions. That info came from the *second* guy I wrote to. Well, just a couple days ago I finally got an answer from the first guy. It doesn't tell us a lot, but it does tell us which maker uses the 1060ish anchors. Here's what he said:

"the short answer to your question is that we use a proprietary steel chemistry that is most similar to 1060. There is no real industry standard and there are only two remaining rail anchor manufacturers�Unit Rail and Portec. Neither of us are willing to share our chemistry and we both believe we have the best solution for the product."

This guy works for Unit Rail, so that's that. Unit Rail uses something close to 1060. (And after looking at their website again, I strongly suspect that their alloy does have more Mn than standard 1060.) Reading that alongside the other guy's response, I'm guessing that Portec uses something closer to 1040.

Now you'll be wanting to know how to tell a Unit Rail anchor from a Portec anchor. I asked. Unfortunately, he didn't have a good answer. Suggested I send in a photo of the anchor, but that's not a long-term solution. We're still stuck with Junkyard Steel Rules.

Matt B - Friday, 08/17/07 17:07:06 EDT

Should've said "which maker uses the 1060ish ALLOY."

Matt B - Friday, 08/17/07 17:07:49 EDT

Halp! My imagination has advanced beyond my current skill, and I need some advice. I'm trying to make a blackberry bush motif sign holder. I'm having trouble with the blackberry(s) though. Blackberries I want to make a mold or a die so I can make multiples out of 3/4" stock. The problems with the things I tried is that I couldn't get the negative deep enough to make it look good when stamped. Any suggestions?

SteelGeek - Friday, 08/17/07 20:10:18 EDT

Bah link didn't work in previous post - cut and paste to get an idea of what I'm trying to make.
http://img.photobucket.com/albums/v311/Steelgeek/Blackberry1.jpg

SteelGeek - Friday, 08/17/07 20:12:05 EDT

SteelGeek,

You have the classic problem of closed die impression work there; deep relief and the necessity to develop sufficient fill pressure and flow. Unless you have a really big powerhammer or hydraulic press, I sincerely doubt that you can do it with a single die. I think there's a way around the problem though.

You might consider making a positive by carefully TIG welding ball bearings into the master berry, then using it to make *two* sets of dies.

On the first set of dies, you'll need to go in with a burr and create some extra room and plenty of easing of sharp corners and edges. Try to increase the diameter of each bearing inpression by about 5-10% and radius all the edges pretty liberally. This set of dies will be used for the initial impression.

The second set of dies are made by first taking an impression from the first set of dies and then using it as the positive for the second set. Then you re-heat those dies and make the final impression in them with your welded-up positive. This way you should be able to get the depth you need in the die.

When making closed dies, it's important to have the two halves of the die in accurate registration with each other at all times. I make mine as spring or "clapper" dies and often put welded-on ears on one side to overlap the other side for extra accuracy. For dies that need to be perfectly registered, dowel pins are commonly used in industry and are easy enough to do at home if you have a drill press.

To use the dies, you need to first rough your stock to the proper volume for the dies, and get your stock to as nearly as possible a ball or pear-shape. This minimizes the amount the metal has to move to fill the die. You can easily figure the volume you need by using displacement - drop you positive in a graduated cylinder of water and mark the level where the water rises. Then rough out your stock until it displaces the same amount of water plus a hair for scale loss.

You also need a way to register the stock in the dies so you're not changing the orientation of the piece form one die to the next. A simple flat spot on the shaft of the stock should do it.

It is important to use plenty of heat for closed die work. The stock must be as plastic as possible to flow well into the impression. Also, the use of some sort of die lube is a good idea. Oil will work, but is smoky and messy. The best stuff I have found is a water-based lube I got from Jeff Reinhardt, aka "ptree". I believe you can buy it in small quantities from Tom Clark at Ozark School of Blacksmithing.

I hope this helps. Let us know how it works out for you.

vicopper - Friday, 08/17/07 20:37:07 EDT

Making a positive out of ball bearings occurred to me also, but I only have an ol' lincoln stick welder, no TIG.

SteelGeek - Friday, 08/17/07 20:50:26 EDT

Steelgeek,
Everything Vicopper said is right on. In the closed die industry, a normal approach for this type work is at least two impressions and often three or four. The first impression is a buster. It just roughs the billet to a very general blank to start the process. If not making many,this one you can skip and use hand and eye. Next would be a blocker, and that is the loose rounded impression followed by a semi finish or finish die.
In drop forges with an excess of force we still used a 7 degree rule for draft. No vertical surfaces in the die. what would be vertical was cut to 7 degrees to allow flow and the forging to come out of the impression. Good surface finish in the die impressions will also help with metal flow.
Vicopper is very right about HOT, and LUBE. For really fine detail a commercial lube is needed. The newer polymer based alkaline salt lubes make oil and graphite look like sand.
We hear on this forum about how much R & D goes into comercial paints and why should we be amature chemists in paint and varnish fourmulation. I say the same applies to forge lubes.
Tom Clark indeed sells the lube. I do not sell this lube. I used to sell some just to get folks to try it. There are several huge companies making these new lubes but only one will sell the tiny quantities that a blacksmith has any hope of useing in a lifetime. Tom Clark and Glenn went out on a limb and bought some quantity and broke it down to user sized packages. I say good on them for making this neat stuff available.

ptree - Friday, 08/17/07 20:53:29 EDT

steven M.

Weld at a "light welding heat", sometimes called a "sweating heat" with no sparks. Sparks are indicative of the incipient burning range and may cause the high carbon steel to crack or crumble. If the billet edges are protected from oxidation with say, an arc welded "envelope", you can sometimes weld at a lemon or a bright orange heat, especially by use of a power hammer.

Frank Turley - Friday, 08/17/07 21:13:14 EDT

we made a die for machine called tdrill end spinner.it is used to spin the end of copper tubing closed by generating heat with pressure.what is the best method to harden this steel die?

kenneth ferrell - Friday, 08/17/07 21:37:20 EDT

SteelGeek,

If you don't have a TIG welder, you could braze the bearings together if have an O/A torch. It would be a bitof a nuisance getting tenor fifteen small bearings all brazed together, but it could be done with some careful jigging with wire and suing pre-cut bits of flattened brazing rod with liquid flux. The trick is to get the whole works set up to braze in one heat.

You should be able to make your dies from a brazed together master if you don't screw around too long and suck too much heat from the dies and un-braze the bearings.

If you can't braze the bearings together, then your next choice would be to make a master by forging and carving, the way blacksmiths have done for centuries. Thisis easier than it sounds, actually.

Start by forging a roughly berry-like shape, a hair oversize. Next, make a couple of "eye punches." These are nothing more than a piece of round coil spring stock that you taper to the desired diameter and then impress a ball bearing into the end of, forming a hemispherical cavity. You need to make two to do the chasinig on the master berry, as you'll need one clamped in a vise to support the backside after you've chased it. If you just lay the thing on the anvil and try to chase the balls in the back side, you'll mash the ones you already did on the front. You will, of course, have forged the rough with a shank on it for handling, but just clamping that in the vise isn't going to provide enough support to work the berry hot, I don't think. Use the back-up punch, as needed,

After forging the rough, then chasing the balls on it, you'll probably need to do some little clean-up work. This can be done with small, sharp chisels and/or various shaped chasing punches you make as you need them. Then clean the surfaces with a scraper to make it as smooth as is feasible and you're ready to make dies.

Low-tech solutions, and forging solutions in particular, are usually the most appropriate means of solving blacksmithing problems. The TIG welder is just a convenient expedient for production work; the hand-forged and chased master will have more character and natural elegance than welded together bearing balls, anyway.

Go forth now and beat your berries!

vicopper - Friday, 08/17/07 21:51:16 EDT

Kenneth,

What specific alloy steel did you use? Without that information, we can't tell you anything but broad generalities like, "Get it hard enough to be abrasion resistant and take a smooth finish."

vicopper - Friday, 08/17/07 21:53:54 EDT

steelgeek I did blackberrys .I went to Iforge and looked at making apples.I reduced the size down to 3/4 pipe made a guillotine to fit.Once i had the berry formed i had a nother guillotine made up out of 1.1/2 in stock.I dilled a 5/8 hole in it then cut it in 1/2 .Then dimpeled the inside of each 1/2 . I made lots of blackberry jam before i got blackberrys

- jmac - Friday, 08/17/07 23:12:40 EDT

Closed die berries: The berries can only get the texture on the top & bottom [as they lay in the die] or You won't get them out of the die. The resdt of the surface will need to be chased with the eye punch. Draft principals apply to closed dies just like in a mold or pattern.

- Dave Boyer - Friday, 08/17/07 23:12:57 EDT

- jmac - Friday, 08/17/07 23:13:18 EDT

steelgeek I did blackberrys.I went to Iforge and looked at making apples.I reduced the pipe to 3/4 in and made a guillotine to fit.Once I had the berry rought out I made another guillotine out of 1.1/2x 4 stock,i drilled a 5/8 hole thrue it .Cut that in 1/2 then drilled dimpes in that made a real nice berry

- jmac - Friday, 08/17/07 23:33:52 EDT

Forge Lube.

The lube that Tom Clark and iforgeiron is selling works great, but it is very expensive.

There is another lube that works as well, and that you can MAKE yourself. I heard it from Uri Hofi, tried it, and was very pleased.

The ingredients: Water saturated with salt, and a little squirt (for a batch in a soup can) of liquid dish soap. Use it just like the other lube, plunge the hot tool in, pull out quickly, water flashes off and leaves a slick film. There is one drawback. It makes a little salt mist in the air which rusts everything iron in close proximity, but you can set it away and all it will rust is the tool and the tongs.

- Ty Murch - Friday, 08/17/07 23:35:23 EDT

Hi, I'm finally getting my own shop, it was a shed about 10' by 8' or so. My thoughts are that it will be a small shop but I only have a few tools so hopefully not too small. My main question is that if I put a 10 to 12 foot smoke stack with an overhead forge hood will it be sufficient to keep the air breathable. It is a coal forge and I was also considering the side draft hood plans on this sight. If one or the other will work better in a small shop like mine then I would obviously build that one. If I'm going to kill myself in a small shop like this please do tell me.

Stephen - Friday, 08/17/07 23:44:28 EDT

I would pay anything that Tom charged to avoid the problems of salt mist in my shop air. Rusting tools waste time cleaning them and they become less useful over time.

Expensive is a relative term, Tyler. Have you priced a stay inintensive care lately? You see, I don't like to breathe chlorine gas any more than I like my tools rusting, and chlorine gas exactly what you will liberate when burning salt. That sounds like a very bad way to try to save a buck or two, to me.

vicopper - Friday, 08/17/07 23:55:17 EDT

Stephen,

I'd strongly suggest the side-draft hood over the overhead hood. I've seen and used both, and the side-draft out-performs an overhead hood by several orders of magnitude.

As long as you don't use too small a flue (10" diameter or better, for choice), and you have somewhere for make-up air to enter the shop, you should be fine with a properly made side-draft hood.

For safety's sake, spend about thirty bucks and get a carbon monoxide detector. Cheap, smart insurance. That way you'll know if your air is truly safe or not, and it's more humane than tossing in a sacrificial canary.

vicopper - Saturday, 08/18/07 00:00:28 EDT

Salt forge lube.
Rich, I try to make some money with my forging, so Tom's lube is expensive for me. Oh, and about the chlorine gas and rust. So what? Coal makes clinker. Beer goes flat if you leave it open.

- Ty Murch - Saturday, 08/18/07 00:35:19 EDT

Are there any other fluxes I could use besides the mixture of borax and ammonium chloride for my forge welding?
Say, mabye that ash soup or what ever it was that the japanese swordsmiths used.

Thank you very much for answer my silly questions!!

troy - Saturday, 08/18/07 01:58:24 EDT

Ty Murch wrote: "Oh, and about the chlorine gas and rust. So what?"

The answer is simple. There is no reason to use substances that are deleterious to your health and tools when better, safer substances are available. There are some hazards in blacksmithing that are pretty much unavoidable, but I see no good reason to add more unnecessarily.

Most importantly, this is a forum attended by literally millions of visitors looking for information. A large number of them are new to this craft and I feel an obligation to present them with the safest possible guidance so that they may enjoy their pursuits in continued good health.

vicopper - Saturday, 08/18/07 06:56:42 EDT

Overhead Hoods: They don't work without HUGE stacks (over a foot of more) OR with an exhaust fan. A side draft is the way to go with min. 10" dia. stack and preferably 12".

Flux: Troy, for ACTIVE fluxes most use borax or boric acid mixes. "ANTI-BORAX" is primarily boric acid. Other patent fluxes use boric acid, borax and iron powder. This is an active flux with a filler. Active fluxes dissolve oxides into and reduce their melting temperatures so they run off or squeeze out leaving clean metal. However, they will not take off heavy scale.

The Japanese use a mixture of rice ash and a refractory (high kaolin or porcelain clay) applied as a slury. This is primarily a cover to prevent oxidation and is not an active flux. The ash is mostly a bonding agent for the clay.

Different Welding Temperatures: You weld at the lowest temperature steels welding temperature. It will bond with the higher temperature steel. The same is true in Mokume' Gane', you braze at the lowest temperature melting alloy's brazing point.

The TRICKY part of laminated steels is defining a correct heat treatment for all the steels and alloys in the billet. There is usually overlap in ranges that can be applied but you need the detailed technical information on each steel. That is where the detail rich ASM Heat Treater's Guide comes in. Much of the information is in graphs that much be carefully read and the information cross referenced. That is, IF you are looking for the perfect heat treat.

- guru - Saturday, 08/18/07 07:05:43 EDT

Salt, NaCl: Not only is this hard on the surrounding steel, tramp bits of it will stick to every tool used. It is like tools used on salt treated lumber then put away. . . TERRIBLE rust. Much worse than normal. Vaporized salt deposits on surrounding cooler steel (including your work) and is VERY difficult to remove. It is not just a dust or gasified salt, it welds to surfaces.

Salt (as flux) is also hard on your forge, gas OR coal. Potters use salt for certain glaze effects and end up replacing kiln linings and heating elements. Coal forges rust bad enough without adding salt.

DIY Die Lube: You can buy the stuff Big BLU sells (I recommend it). It may seem expensive but the little bottle of concentrate goes into a MUCH larger amount of water. Should last a year or so in a typical small shop.

If you want to make your own it is graphite powder, a dash of molybdenum dioxide (a little goes a long way), detergent and a little water (you guess at amounts, I'm not giving away trade secrets). This is applied to tools and let dry or you can dip warm tools in it while you work. The graphite and molybdenum dioxide are good at very high temperatures and both very slick. The molybdenum dioxide is an especially small lubricating molecule and fills pores and microscopic irregularities in metal. The mixture is non-reactive and does not rust your tools. You can apply it in advance to sets of tools so they are always ready to use without an extra step. However, as with many dies lubes reapplication is necessary.

- guru - Saturday, 08/18/07 07:32:47 EDT

Punch lube is available in small quantities in a user-friendly container on eBay. Just do a keyword search on punch lube.

It will also be available to Quad-State on September 21-23.

Ken Scharabok - Saturday, 08/18/07 07:39:23 EDT

Craig: On the ATTWOOD it is possible it was made for the export market to a country using the pound system. RECORDs in England today are marked both in kilos and pounds.

Anvils have a way of traveling around. For example, some HILL (Burmingham, England) have been found in the U.S. However, Richard Postman has found no advertising for them in national mail-order catalogs and such. Most seem to be in the Pacific NW. Speculation is they were exported to Canada and some found their way south of the border. (Someone on eBay advertised a TTIH anvils. HILL upside down.)

Why would a Trenton show up in Australia? Likely shipping from the U.S. there as a purchase would have been rather expensive. Perhaps formerly owned by the U.S. military who left it in country after WW-II? Perhaps included in the household effects of someone immigrating from the U.S. to Australia? Some anvil sellers in the U.S. have implied it was originally brought to the U.S. by an immigrating ancestor.

Oh, if anvils could talk. I suspect some have had VERY interesting histories. How many FISHER & NORRIS anvils saw battle in the Civil War and those since? I suspect several large anvils (probably FISHERS) lie within the USS Arizona today.

Ken Scharabok - Saturday, 08/18/07 07:56:01 EDT

Fie? Pish posh? Sir, no need for such language here at the forum! :) The wire sculpture posted is a representation of a cube in hyperspace, a tesserac (no T, oops on me). U further representation would be an opened cube, then that would be cubed, kind of like a cross made of cubes (see works by Dali). Either way, you should have said "orthogonally" and not "twin that"..... confusing, eh? Don't feel sorry. Thanks for saying my work is purty!

- Nippulini - Saturday, 08/18/07 09:32:10 EDT

Alkaline salt lube for forging.
The alkaline salt lubes represent millions in R & D. Then there was the trials in industry. At the shops I worked at, we spent more on lube than the one can ever imagine. We were using 7 totes of 350 gallons of concentrate a week at the last big forge I worked at. Now that was expensive! That shop had been a graphite shop prior. Everything was black/grey from the graphite smoke, including the people, inside and out.
The graphite needs a binder to stick to the tools, and most of the binders smoke also. We changed to the polymer binder alkaline salt lubes at TWICE the per pound cost, and save huge amounts of money. The alkaline salt lube made the tooling last much much longer, and allowed the metal to flow with much less force, saving wear and tear on the machines.

Cost of the lube is actually tiny in a blacksmith shop. I have the same quart, that has been in use in my admittedly weekend shop since 2002. I do have to add back water as it evaporates, and I did spill a smaller dip pot I had by the vise. I have a stack to remove coal smoke on my shop, and on my demo trailer as I don't want to breathe that stuff, and I will not breathe graphite smoke either.

Last but not least, the graphite and soap combo's stick but flake off leaving no lube. The alkaline salts stick like no other forge lube I have seen. Tom clark was a graphite and soap guy till I gave him a small sample in 2002. He tried it, and has never gone back. Heck he drove several hundred miles out of his way to get some more from me. Vicopper tried it, and went to the trouble to arrange for delivery at Quad State, and then ship it home on his own.
Most of the folks that say this stuff is expensive or not needed or so forth have never tried it. Most of them will spend $100 for a special hammer, and so forth but not less than $20 for what is really a life time supply of excellent safe lube.

ptree - Saturday, 08/18/07 09:59:58 EDT

Guru,

On the DIY lubricant, wouldn't the molybdenum compound be MoS2, molybdenum sulfide, rather than the oxide?

vicopper - Saturday, 08/18/07 10:51:46 EDT

what is the steel content of swords that were used by the british in the late 1700's

donnie ross - Saturday, 08/18/07 11:24:22 EDT

Punch Lube I bought a gallon of the concentrate ptree is talking about it is great stuff and at the time I beleive the cost was $35 or so with shipping it works great I use it for punching and in closed die forgings. If you are in the buisness of making money, then one way to look at making things like punch lube is it will take me 1/2 an hour or so to come up with a possibly toxic mix that will cost some in materials and 50 dollars in shop time or you could spend 35 tax deductable dollars and order a ready made product that is known to work well. then use it to make some money

- Aaron - Saturday, 08/18/07 13:20:29 EDT

Aaron, Glad to here the punch lube works well for you. What % are you running? I have been asking folks and most say in the 5 to 20% range.

ptree - Saturday, 08/18/07 13:33:57 EDT

TGN-- Sirrah! Sheer flapdoodle! Nay, utter balderdash! The unit A is still what is what the model is intended to represent, no? If you change the length of that in the second cube , as you have done, then it becomes not a model of A squared or A cubed, etc., but something altogether else. It becomes 1.5 (A cubed), or 2 (A cubed) or .75 (A cubed). Sorry about that.

Miles Undercut - Saturday, 08/18/07 15:33:12 EDT

Aaron,

Well stated, and absolutely correct. I am a full-time working blacksmith these days and I simply cannot afford to waste time on concoctions that either don't work as well as they should or that have toxicities. The forge lube from ptree/Tom Clark/Ken Scharabok is the real thing and gives me great punching ease and very sharp die impressions. Why mess around with anything less?

Jeff,

I've been using it at about 10% concentration, but I really think I'm running it stronger than I need to. I think 5-6% would do just fine. Great stuff, thanks for putting me on to it.

vicopper - Saturday, 08/18/07 15:46:16 EDT

I just got a Clarke 4 1/2 inch band saw. Yes, I know it is a crappy, cheap tool but for a hobbyist like me it is probably as cost effective as needs to be. I will need to get a better blade as the one that came on it seems to have some flat teeth. I am going to check if the warranty covers that. The saw is much better than hand sawing and the cut off saw I had made out of an old Circular saw. I will make a better vertical cutting table though. the one supplied is about worthless, just a piece of thin sheet metal. Any suggestions on blade sources. I dont think I have the ability to weld up my own yet.

JLW - Saturday, 08/18/07 17:20:13 EDT

is there a good way to form a rectangular piece of thick sheet metal into a cylinder in a home shop. It is too thick to bend by hand. I am open to suggesions. I only have a selection of hammers and an anvil for tools. Maybe hammering it around a log or something. If anyone can help me avoid reinventing the wheel I will be grateful.

JLW - Saturday, 08/18/07 17:25:24 EDT

JLW,
The small cut off band saws , once trued to cut straight, really benefit from a Bi-metal blade. All the name brand makers have them. I prefer Lennox, in the Die Master II, in a 10 to 14 tooth variable pitch for thicker sections. For the really thin wall sections I use the same in a "Porta band" style in a 28 tooth, if I recall the pitch correctly.
I get mine from Mike Morrison at Hagemeyer at 502-961-5930. I just bought 10 of each for the long haul, and paid just under $20 Each.

A tip, with these little saws, the table is little help for vertical cutting. They are all too thin, but the blade width these saws use does not allow much other than straight cutting. Use you old blades for cutting on the table as you will dull one side more than the other and they will not cut straight in the cut off mode.

If you always make sure that the stock is tight in the vise, and don't cut too thin stock and strip the teeth, these blades last a very long time and a bi-metal blade far outlasts the plain blades.
Another tip, always use a blade that has at least 3 teeth in the cut. If the blade has less than 3 teeth engaged in the cut they will strip off the band.
Good luck

ptree - Saturday, 08/18/07 18:46:24 EDT

JLW,

I don't know how big a cylinder you're trying to form, so it makes it a bit difficult to offer specific guidance. In general though, it is easiest to start a concave curve using the angle formed by the step of the anvil between the table and the top plate. From there, you can find a suitable piece of pipe to finish forming the cylinder around.

Another way to form sheet metal into cylinders is to clamp one edge of it to a piece of pipe and then roll the pipe on a flat surface. For this, you start with a pipe that is a good bit smaller in diameter than the cylinder you want, to allow for spring back.

vicopper - Saturday, 08/18/07 19:05:25 EDT

Before I had an anvil, I made sheet copper cones by supporting a 1/2" drive socket extension at both ends and working the copper over it with a rubber mallet. Same think could work for steel cylinders, if the piece was of reasonable dimensions and thickness.

Mike BR - Saturday, 08/18/07 19:19:50 EDT

Thanks for the advice. The cylinder is about 9 inches in diameter. Maybe the size of a small compressed gas cylinder. Hmmm.
About the saw, I wonder if I stripped some of the teeth by cutting a piece of thin steel bar on edge, it is about 1/8 inch and may not have had the 3 teeth on the work. I guess I should have had it down flat.

JLW - Saturday, 08/18/07 21:23:12 EDT

I heard forging the edge of a blade at colder tempatures makes it have a finer grain and stronger.
Is this called edge packing or austenite forging or both?
Would you tell me a little about it?
thanks!

- stephen M. - Saturday, 08/18/07 23:34:18 EDT

Steel in Early 19th Century British Military Swords; Donnie Ross:

I'm still unpacking my books from a very recent move, and the relevant volumes haven't hit the shelves yet. I would suggest that you run your question by Sword Forum (
http://swordforum.com/ ) in the "Antique and Military" forum at that site. They can probably steer you straight faster than I will at the present. My best guess, without supporting information, would be plain 60 point carbon steel, or somewhere in that neighborhood.

Cool and light clouds on the banks of the lower Potomac. Boxes and boxes of books to go.

Visit your National Parks: www.nps.gov

Go viking: www.longshipco.org

Bruce Blackistone (Atli) - Saturday, 08/18/07 23:41:59 EDT

Why does carbon content affect welding temp
Thanks.

troy - Saturday, 08/18/07 23:53:31 EDT

JLW: I just use the little plate that is always on My 4x6 saw, it is only a coupple inches square, but hasn't been a problem in the 24 years I have had the saw. It is small enough to stay on for horizonal work, and supports the area just around the cut for verticle work. The 10-14 pitch Die Master II blades work well in 1/8" material [] I have used them on 3/32" & less too] in spite of the 3 teeth rule, just start carefully.

- Dave Boyer - Sunday, 08/19/07 00:30:12 EDT

molybdenum disulfide, yep I got in a hurry. . . .

Troy, The higher the carbon the lower the melting point. Cast iron melts hundreds of degrees F lower than steels due to the higher carbon. The slurry "austinite" range where near solid phase welding occurs is even hundreds of degrees lower than the melting point for high carbon steels and the burning point even lower (carbon burns out of the steel and causes it to burn as well).

Stephen, Edge packing is pretty much a myth IF the steel is heat treated afterward. Thermal packing by heating up to the hardening point and letting cool slowly one or more times IS beneficial and makes a huge difference.

Tube Making, A brake type arrangement of two round bars welded to a plate and a third to bend with can make smooth curves in a variety of thicknesses depending on how you push it and how close you space the bends. In a hydraulic press you could easily do 3/8" thick bar and short plate. In a vise, arbor or screw press you could do 1/8" without great effort. By hand 16ga would not be a problem.

JLW, The Lenox be-metal HSS edge blades are some of the best and make the saw perform a LOT better. MUCH MUCH better than the difference in cost would indicate (which is a lot). I ordered from McMaster-Carr and got Starrett brand which should be just as good (or may be the same blade).

I agree with everything said above about these saws. Note however that I have looked at several that are NOT heavy duty enough to extend the table ANY AMOUNT. If you have light sheet metal brackets then do not try to improve the table, do not try to use it vertically.

NEVER turn thin work on edge, even if you have the 3 teeth minimum. You get much more accurate cuts lying down.

SPENT the day on the road moving tools. . . One tool chest (top only) and a rack of blacksmith's tools was about the maximum capacity of my van. . . Need to make a second identical rack. And this is the SMALL stuff. Working on the hammer-in. . .

- guru - Sunday, 08/19/07 00:43:55 EDT

Several months ago I upgraded from a small garage (4 1/2") bandsaw to a (I think) 7" x 12" one. Sold the small one and now wish I hadn't. I could have taken it off its base, mounted it on a table, and used it for some short-length projects.

Small one was something like a 68 1/2" blade. I talked to Mike Morrison (at Hagemeyer - 502-961-5930). At the time he couldn't locate this size blade from his suppliers. My larger bandsaw is 94 1/1" (IIRC). Lennox does do them. He recommended three blades: For normal mild steel: 47435-CLB7-236. For mild steel fine work (e.g., angle iron): 72100-CLB7-236 (these are only 1/2" wide so allow me to use the saw somewhat in a vertical position as it leaves a bit of the table for resting the stock on). For tool steel: 80310-D2B7-236.

I have ruined a couple of the regular mild steel blades using them to cut thin material (apparently violated the three teeth rule). Once a couple of teeth are knocked off the rest of the blade is doomed. The thin stock ones work nicely on slow speed. I was surprised in the tool steel ones really did work - even for stainless. I did keep squirting the blade with WD-40 though.

On my bandsaw changing the speed of the motor is somewhat a hassle. Have found it works fine at just the slowest speed. Takes longer, but then I'm usually not rushed anyway.

Ken Scharabok (Poor Boy) - Sunday, 08/19/07 08:28:17 EDT

Ken, The lennox blades I buy are factory welded to the lenght I specify. I thinl mine are the standard 4 x 6" size and are probably 68.5 by .5 x .025. I will check in a bit.
The thin stock will indeed strip those teeth. I have started to keep the old blades that have good sections, and I can cut them to lenght and I drill the mount holes to make them into hack saw blades. The course bi-metal blade in a hand hack saw cuts great, and I only spend maybe 2 minutes a blade to make them.

ptree - Sunday, 08/19/07 09:58:44 EDT

I have both sizes of bandsaw in my shop, and while the big one is handy for the occasional piece of 6" square tube, the little 4x6 gets used ten times a day.

I have had good luck with the Jet brand saw- I am on my 4th, which, for 30 years in a 3 man shop, I think is amazing longevity for a $300 tool.

All the big mailorder suppliers, MSC, Enco, McMaster, and so on will sell you 68 1/2" blades, welded to order for these saws.

And there is no doubt the bi-metal blades are much better. Like Ptree, I use the 10-14 variable pitch Lennox most of the time.
These are not inexpensive blades- usually $25 or so, each. And in our shop, we order 3 to 5 at a time- yep, I spend as much, annually, on blades, as the saw cost.
Saw blades are a CONSUMABLE. They do not last forever. And once you screw up, and drop the saw down on the work, or try to cut too thin of material, or let something bounce while cutting, and knock out a tooth, the whole twenty five buck blade is shot very quickly.

But what you can do with those blades is worth the price of admission- dont cheap out on blades.
In my shop, used daily, mostly on stainless, a Lennox blade can easily last a month or two. Or a day. Which is why I order extras.

- ries - Sunday, 08/19/07 11:41:58 EDT

Blade sizes:The "standard" 4x6 clone saws all use a .025 x 0.5" x 64.5" long blade.

On ALL band saws that twist the blade (cut off types) you use only one size blade. The wheels do not have a rubber tire but have a shoulder for the back of the blade to run against and a chamfer to clear the teeth. If you run narrower than standard the teeth cut into the wheel OR the set is ruined in the blade IF you run wider then the blade is not properly supported and will not stay on.

Quality: On the blade twisters I have found that the weld MUST be perfect and properly trimmed and tempered. I originally started to buy cheap blades from a local supplier that welded them poorly. The welds failed long before the teeth. The fancy bimetal blades like the Lenox require special welders and special care in welding. Lenox is also picky about selling bulk blade to folks without the proper equipment because it reflects on their blades.

The "cheap" blades I was buying cost only $3.50 each in the 1980's. A Lenox bimetal cost $16 (now $22). But the Lenox bimetal blades were MUCH cheaper to operate. One blade would outlast a dozen or more of the "cheap" blades. Besides the cash difference there is also all that labor changing blades.

Using 10-14 HSS bimetal blades I run full speed on everything, stainless, tool steel. . . This is about 220 FPM on my 4x6 saws.

Using too fine a blade lets the blade wander. The fine blades (even the expensive ones) often rely on a wavy edge for clearance. A good set on a coarser blade is much better. So run a coarse blade as often as possible and only change to the fine (18TPI) blades for cutting thin metals.

I cut most angle iron on the diagonal. Somewhere in a book I saw it listed as a NO-NO due the corner. However, if you do not start the saw gently on EVERY cut you are likely to strip teeth. After a gentle cut the angle will cut smoothly at a continuous rate rather than drop through the vertical leg then slow down for the flat. Cutting through the legs on the diagonal also lets you cut thin angle with a coarser blade safely.

In our shop we have two small machines, a 4x6 saw and a 6" lathe. Both get used a LOT more than the big saw and lathes because they are more convenient as long as you are in their capacity. I did occasionally have to get after the guys about waiting 20 minutes to cut a piece of 3" round on the small saw when the big saw a few feet away would do it seconds.

- guru - Sunday, 08/19/07 12:00:13 EDT

What is the difference in a hot and cold cut chisel or hammer

rockingwj - Sunday, 08/19/07 14:15:24 EDT

Rockingwj,

A hot cut chisel generally has a much more acute (narrow) cutting angle that a cold cut, as the cold cut must be able to withstand the greater resistance of cold steel.

With modern hot-work alloys such as H-13, hot cut chisels can be made with an included angle of only 5 degrees and still hold up to the task very well. Older ones made of ordinary 10XX steel have to have an angle of at least 12 degrees or they absorb too much heat too quickly and rapidly lose their edge.

Cold cutters usually have an included cutting angle of about 45-60 degrees for toughness.

vicopper - Sunday, 08/19/07 15:00:50 EDT

Ptree On the punch lube I started at about 10 % but I live and work in Santa Fe NM ,its dry the lube evaporates I add water it seems to work well across any range I have diluted it to.

- Aaron - Sunday, 08/19/07 15:01:15 EDT

JLW: I had a small HF bandsaw that took a 48-1/2" blade which I always had to have made up for us. I found that the 18 or 24 tpi blades with a wavy rake worked best. I found the bi-metal hard baked blades worked best and got them from KBC tools. Only once in 20 years did I get some that they welded up backwards!! As for the useless table for for verticle use (I never used it horz. - I used a big Rigid for that) I took some 1x1x1/8 angle iron and bolted it to the bottom of the stock table with countersunk flathead screws to stiffen it up and it worked great. BTW the saw always cut a little off straight, but always predictably so, so it was never a problem if you fved it right!!
Jeff

Jeff - Sunday, 08/19/07 15:11:47 EDT

JLW: Like -guru says: one high quality blade is much less expensive than 10 cheap ones. I used Lennox or Starrett only. Most of my work was in 10ga. or thinner.

Jeff - Sunday, 08/19/07 15:20:04 EDT

Lennox blades, I paid $19.78 each i think. As i am local and the Hagemeyer truck delivers other stuff to my shop I don't have to pay shipping. I have never had a bad Lennox blade.

Like the Guru, I cut angle on the diagonal. I loosen the movable vise jaw a bit and it rides up over the bottom edge of the angle locking it securly so it does not try to rotate when I cut.

When i got my saws, a Jet and a Jet wannabe, I trued the back vise to the blade with a machinists square, and scribed a line on the table. I then swung the vise and set to 45 degrees and again scribed a line. The angle markings are just a sticker and not near accurate. The lines make for a quick set up.

I always check a new saw of these type to insure the gear box has liquid oil in it. I had one at the valve shop that was filled with grease, and it failed pretty quick.
I also usually add some moly disulfide to the oil.

ptree - Sunday, 08/19/07 17:02:57 EDT

Punch lube.
The comercial shops run 5%, but tend to spray after every hit. More concentration and the lube builds up in the dies, and changes the forging. I am running at about 20%, but since I mixed it long ago, and have used and added water as it evaporated, I am not sure what the % is now. Still works a treat. Mine has frozen many many times as well, and I see no change.

ptree - Sunday, 08/19/07 17:05:34 EDT

Stephen M.

I see this "packing" steel referred to in the older blacksmithing books, especially Holford's "Twentieth Century Toolsmith and Steelworker". A student, Harry Jensen, who worked for the Third Reich as a POW in WW II, dressed mining tools and he swore by it. He said that it definitely worked. I have also heard packing referred to as "refining steel", which sounds like a misnomer.

I think Holford suggests using flat overlapping blows just behind the cutting edge at a faint red into a black heat. He claims that when you finish hammering, the metal should show a bright black surface gloss where hammered. This is done only on relatively flat tools such as axes and chisels. Jensen used the same sort of heat on the mining chisels, did a quick zig zag with the hammering and finally one blow on the left behind the cutting edge, then one on the right, then one a little closer to the edge, in the middle. In any case, the workers were doing this on unalloyed plain carbon, high carbon steel.

I don't know whether packing works or not. To my knowledge, no annealing was done after the packing. Annealing might undo any "grain distortion" or work hardening that the packing blows imparted. I think that after packing, the next step was hardening.

I've written about this, because the subject comes up occasionally. Personally, I do not pack; I most often will normalize high carbon steel after forging to shape.

Frank Turley - Sunday, 08/19/07 21:19:17 EDT

VIOLATING the 3 TEETH RULE: When You do this You need to keep the feed pressure low, and start into the cut slowly. Keep the blade speed up, the 220 fpm on the 4x6 saw is OK. when using My 4x6 saw in the horizontal mode I keep My hand on the saw to relieve the down pressure throughout the cut. I am not advocating using too coarse a blade when You are going to be doing a LOT of fine cutting, but if You were to change the blade every time You needed to cut a little thin stock You wouldn't get anything done.

- Dave Boyer - Sunday, 08/19/07 22:20:41 EDT

Dave is perfectly correct. When you have to cut that occasional piece of thin wall tubing or EMT you can do it without damaging the blade if you reduce the feed rate by holding back on the saw. On these items it tends to start slow on the parallel surface then try to quickly drop through the sides of the tube. If you do not reduce the feed rate at this point you can strip teeth.

A few of the cheap saws have hydraulic feed speed reducers (shock absorbers) that can help in this regard. The old reciprocating saws had a ratchet mechanism that let the saw only feed so much per strike and this helps as well.

- guru - Monday, 08/20/07 07:43:29 EDT

I would like to forge some sickle blades. How do I forge so the edge is on the inside of the curve? Sharp on the outside like a sabre is easy but how do I reverse this?

- philip in china - Monday, 08/20/07 08:02:05 EDT

I would like to forge some sickle blades. How do I forge a curved blade with the edge on the inside of the curve? The edge on the outside like a sabre is easy but I don't see how to reverse the process.

philip in china - Monday, 08/20/07 08:06:46 EDT

Sorry for the double posting. I thought the original one had disappeared. Having a bad week!

philip in china - Monday, 08/20/07 08:08:16 EDT

Philip in China,

I made a sickle once for a museum exhibit, but I don't remember how I did it. I think I would do it the same as a knife or sabre, but I would over-bend on edge into a semi-circle, more or less. Then hammer on the concave flat with angle blows, allowing it to straighten a little.

Fine tune in a bending form. In the Southwest, we make curved firescreens, bending flat stock on edge, for beehive shaped fireplace openings. I made a "bending fork" with a horizontal ¼" plate bottom and top, the distance between plates a tad more that the working stock thickness. There are two vertical pins, one pin fixed between plates and one removable. The removable one gets fit through drilled holes in both plates and hits a welded stop a little below the bottom plate. A welded leg goes into the vise. It's ugly, but it works.

The removable pin allows one to work a long flat on edge, bending the hard way, so that you can quickly remove it without drawing it all the way out of the device. The top plate helps to prevent buckling, although there will be some. For the fire screen shapes, I use it on cold iron, although hot iron could be inserted.

Now I have a question. Most Western sickles have filed[?] lines on one side of the cutting edge, not at right angles to the edge. What's that about, perhaps creating a serration?

Frank Turley - Monday, 08/20/07 08:59:32 EDT

sickle serrations.
It's my understanding that sickles used for cutting grains are supposed to be serrated because they are to be used with a sawing motion to cut the stocks. This reduces the grain that is lost that would be knocked out of the head otherwise.

JimG - Monday, 08/20/07 10:34:53 EDT

Phillip, I would do as Frank suggested and over bend. Often these are are staggered processes. I would start with round stock, flatten some then bend, then draw some more and over bend then draw some more. If the outer edge is hot it can stretch and not compress the inside if it is cooler. If you leave the outer edge thicker than the finished thickness as you work you can flatten it to increase the curve.

- guru - Monday, 08/20/07 11:23:51 EDT

Packing edges: well in the "bad old days" where you had pretty much straight carbon steels with no other alloys and they were often worked quite hot because the smiths did all their other work with real wrought iron; grain growth was a real problem---especially with thin sections like blades which tend to overheat anyway.

Nowdays we add alloying elements that help retard grain growth and help refine it during heat treat---why knifesmiths often normalize a blade three times as the first step in heat treat.

Back then your basic method to refine grain was to hammer it to "break up" the large crystals into smaller ones---(putting in enough dislocations that they renucleate smaller crystals during heat treat)

Unfortunately a lot of smithing "lore" that gets handed down has a basic problem in that things have changed on the metallurgical front and these changes have *not* made it into the collective memory.

When making something like a thin knife blade you can run the risk of damaging it by hitting too hard too cold---though the cracks often then get blaimed on the quench. If you are using modern steels it is better to use heat treat to refine the grain not forging!

Of course edge packing is part of the hype some bladesmiths use to differentiate their product. Note especially that some folk claim that it makes the steel "denser"---this is just wrong.

Thomas

Thomas P - Monday, 08/20/07 11:46:27 EDT

Traditional edge packing involves multiple heating and cooling cycles that end up looking very much like the thermal packing the Guru described. My strong suspicion is that old-time smiths accidentally stumbled upon the grain-refining benefits of multiple normalizing cycles (thermal packing). But they mistakenly believed that those benefits had to do with the hammering they were doing, rather than the heating and cooling that accompanied the hammering.

I'm not suggesting that anyone should edge pack *now.* What the Guru refers to as thermal packing will produce better, more predictable results without the risk of cracking the blade by hammering it cold. (It's very commonly used by modern bladesmiths.) The only point of my little theory is that the old-time smiths probably weren't crazy to believe that edge packing was worthwhile. They just didn't understand *why* it was worthwhile. Real phenomena, misunderstood: I think a lot of superstitions begin that way.

Matt B - Monday, 08/20/07 11:56:10 EDT

Active and passive fluxes: one of the main thing a flux needs to do is to help get the scale out of the joint so that steel can bond to steel.

Now scale will melt---but at a pretty high temperature; a lot of old fluxes were basically passive just helping to protect the surface of the metal until it reaches a temp where the scale melts on it's own. Worked pretty well for wrought iron and wrought iron derrived steels that can generally take a higher temp without burning than modern steels.

So you had things like powdered glass, clean quartz sand, rice straw ashes, (contains silica), dirt daubers' nests even wood or charcoal ash---seems like silica was the "active ingrediant" with a lot of these).

Now with modern steels they often weld at lower temps and burn at lower temps as well; so you want a more active flux to help lower the temp that the scale melts at and help clean the metal as some of those alloying elements form oxides that are hard to get rid of.

Borax is probably the simplist of the active fluxes; then using it as a base you can add in more active stuff like boric acid, flourspar, etc.

James Hrisoulas once posted a flux receipe he likes calling it "Steel Glue":
"5 parts anhydrous borax
2 parts powdered boric acid
1 part powdered iron oxide (the real STUFF NOT the concrete dyes)
1/2 part Flourspar
1/4 part sal ammoniac
This stuff sticks most anything together"

Generally I'm not forge welding high alloy steels and plain borax does ok for me.

Note that fluxes using flourspar and other reactive compounds ARE NOT GOOD TO BREATHE, especially at forge welding temps. Flourine gas does not play nice with your lungs!

"Practical Blacksmithing", Richardson, was written during the switch between wrought iron and wrought iron derrived steels and bessemer/open hearth steels and has several discussions IIRC on having to change fluxes for welding the "new" materials.

Note also that if you need to buy boric acid you can buy it at a pharmacy for a lot of money for a very little bit or go to a hardware store and buy roachproof that is about 98% boric acid with a bit of inert stuff in it. I'm cheap, no roaches in my forge!

Thomas

Thomas P - Monday, 08/20/07 12:09:52 EDT

Matt, multiple normalizing does not refine the grain of old steels *without* deformation to allow it to renucleate new smaller crystals.

Of course most people will never work with such old materials anyway. (we're talking of stuff that is on the order of 150 years old or older) Of course if you are smelting your own from ore in a bloomery process...

I have some 1828 High Carbon steel that I will be making a knife out of that I will edge pack though...

Thomas

Thomas P - Monday, 08/20/07 12:17:30 EDT

Thomas,

Why not?

Matt B - Monday, 08/20/07 12:37:25 EDT

punch lube

I use regular "Never Seze" . Same stuff I ues on the trucks, so we can get them apart again. I't a graphite mixture. I don't punch much,but it works and doesn;t smell to bad. If TC's stuffis better I'll get some.

Steve Paullin - Monday, 08/20/07 13:08:09 EDT

Matt; can we ring in a metallurgist to explain how they tweak the alloying so to make it refine grain theough heat treat?

Patrick, Quenchcrack, ?

The basics IIRC is that there is no reason for the crystals to reform if you just heat and cool, they should just slowly enlarge as they hunt for the lowest energy state; you need something to make them change from large crystals to smaller ones (which are at a higher energy state due to all the boundries) deformation works and there are alloying elements that will work as well. Old steels do not have such elements save perhaps for some specific ore bodies that may include a subset that may or may not make it into the metal produced from that ore body.

Thomas

Thomas P - Monday, 08/20/07 14:00:03 EDT

I just happened on this site and saw where seveal people were asking about forced air gas forges. Riverside Machine (Uncle Al the knifemakers pal) and Darren Ellis at Ellis Custom Knifeworks also sells the forge and all the parts to build one. I used the plans at www.dfoggknives.com to build the one I have. By scrounging around and using the propane regulator I already had, I spent less than thirty dollars. It will reach welding temperature with no problems.

Da;e - Monday, 08/20/07 14:20:27 EDT

Recrystalization of steel: Steel BEGINS to form austenite when heated above 1333F. The austenite continues to form up to the A3 or upper critical temperature which is controlled by carbon content (check an Fe-C phase diagram for details). The A3 temperature drops as carbon content increases to the eutectoid point of about .78% C. It increases again after .78. Above the A3 the austenite can really begin to grow by incorporating its smaller neighbors, like big soap bubbles swallow smaller ones. If you heat to a temperature just above the A3, you will get a fully austenitic steel with the smallest grains BASED UPON THE PREVIOUS GRAIN SIZE. If you heat above the A3, then hammer the piece to crush the austenite, then cool the piece rapidly (not quench), you will form very small ferrite grains in the crushed austenite. When you re-heat above the A3 again, austenite forms at the ferrite grain boundaries and you get a finer austenite grain size. Finer grain size improves toughness but lowers the hardenability of the steel. In plain carbon grades, this can be significant. Modern steels add aluminum, silicon and exotic stuff like vanadium to control grain growth at high temperatures. Al and Si are added to deoxidize the molten steel and the grain size control is kind of an added benefit. They precipitate at grain boundaries and prvent growth of the grain. However, over about 1800F the oxides and nitrides these elements form begin to dissolve and the grains begin to grow again. By the way, the crushing the austenite and rapid cooling is done every day in the steel industry and is called Recrystalization Controlled Rolling. It is used to strengthen low carbon steel plate and strip without further heat treating.

quenchcrack - Monday, 08/20/07 17:34:50 EDT

PS: I just found my forge! It was in the second to the last box we opened in the garage after the move. Figures.

quenchcrack - Monday, 08/20/07 17:37:23 EDT

Bob,

That tells us that forging can alter grain size, which is good to know. (Although I'd expect hammer forging, especially, would tend to produce a very uneven grain size that would require normalizing to sort out.) But is there any reason that you shouldn't also reduce grain size in plain carbon steels simply by thermal cycling? I know beyond a shadow of a doubt that it works on 10XX steels.

Matt B - Monday, 08/20/07 18:16:17 EDT

Er, I meant, "shouldn't also BE ABLE TO reduce . . . "

Matt B - Monday, 08/20/07 18:27:27 EDT

3 tooth rule and the stripping of bandsaw teeth.
Being a good scrounger, I bought one saw and the other was surplus to the needs...
I keep a 24 tooth fine blabe on one and a 10 to 14 variable on the other. Also handy to cut angles that are different on each end of a production run of parts.
I too have done the low feed and a prayer, with a course blade. And I too have ruined several expensive blades.
One of the things that takes longest on changing the blades if twisting the little knob to remove it to open the cover. I replaced mine with a short peice of 10 Ga copper bare wire bent about 100 degrees. In and it stays out in one second. Not a forethought thing, I lost the knob:)

ptree - Monday, 08/20/07 19:04:42 EDT

Matt: Note my comment: "If you heat to a temperature just above the A3, you will get a fully austenitic steel with the smallest grains BASED UPON THE PREVIOUS GRAIN SIZE." The answer to your question is clearly yes. Simply normalizing CAN reduct grain size but you need to normalize at the lowest temperatures for the carbon content of the steel. Normalizing too hot will allow grain growth and the just defeats the purpose.

quenchcrack - Monday, 08/20/07 19:55:53 EDT

Thanks, Bob. I wasn't sure what you meant by "based upon the previous grain size." I thought perhaps you meant something like "no smaller than the previous grains."

Matt B - Monday, 08/20/07 20:05:33 EDT

If working with a known steel alloy I would urge You to follow the manufacturers suggestions regarding heat treatment, including normalizing after forging. Specifically, A2, A6 & D2 normalizing after forging is not recommended by Carpenter, I would tend to take their word on it lacking the R&D department that they have.

- Dave Boyer - Monday, 08/20/07 21:25:17 EDT

Why does carbon content affect forge welging heat???

Please respond.

troy - Monday, 08/20/07 22:25:38 EDT

Troy, the Guru answered your question immediately after your original post. Instead of getting bent out of shape (bs pun intended) take your time and Read What Others Have Posted

- Charlie Spademan - Tuesday, 08/21/07 08:00:50 EDT

"Bent out of shape"... is that an arcane blacksmith term thrown into modern vocabulary? When I accidentally bend metal out of shape I get a little angry. Same thing if I lose temper. I've had to test my metal as well. I try not to have too many irons in the fire.

- Nippulini - Tuesday, 08/21/07 10:36:10 EDT

Hi, i want to start doing my own hot dip galvanizing, what will i need?

markj - Tuesday, 08/21/07 10:47:20 EDT

Matt B, remember most modern 10XX steels have a pretty substantial manganese content. Mn helps control grain growth to an extent, but also greatly increases hardenability.

For the record, it seems that what you, Thomas, and QC are dancing around (well, Thomas actually said it) is the issue of grain refinement in pre-bessemer steels and how sub-critical forging might help edge retention in such steels. Is that basically it?

If so, I'd suspect a crucible or "cast" steel a'la Huntsman would behave most like modern steels, rendering the whole edge-packing thing of little use. However, if you're talking shear steel produced by carburizing wrought iron, there may be something to it. The laminated structure of shear steel might do odd stuff to grain growth patterns, with the slag stringers acting as physical boudaries preventing grain consolidation. Whaddaya think?

Incidentally, the iron ore bodies around my area are so high in manganese that some were used as dual-purpose ores for either! Makes some darnedly tough wrought iron that was valued for wagon tires back in the day, and no doubt produced a good shear steel.

Alan-L - Tuesday, 08/21/07 11:52:02 EDT

How are sheet metal cones roll formed. I have a 3 foot Pexto slip roller with standard rollers and have tried unsucessfully to play with loosening one end of the roller assembly.

I have seen hints/references that spcial conocal rollers are required. Basically I am currently forming half circle blanks into cones by hand over a mandre,l with good results, but it is to slow for the quantity that Ineed to fabricate.

Any advice will be appreciated

Dan

Dan - Tuesday, 08/21/07 12:11:04 EDT

Alan-L, as regards to a Huntsman steel acting more like a modern steel - I've got to believe it would be more dependent on the chemical composition than the manufacturing method. I'd suspect that the early Huntsman steels were nearly carbon iron alloys and as such might have reacted similarly to shear steels of the period.

- Gavainh - Tuesday, 08/21/07 12:24:41 EDT

Alan,

My theory was that the cold(ish) forging involved in so-called edge packing had very little to do with grain size, but that the repeated thermal cycling that was involved in the process very well *might* have produced a grain-refining effect, just as many modern bladesmiths refine the grain of forged blades through multiple normalizing cycles (sometimes multiple quenching cycles) at progressively lower temperatures. Thomas suggested that that sort of thermal cycling wouldn't affect the grain of, for want of a better word, primitive steels. (Pre-Bessemer is probably a better way to put it.) I didn't -- and don't -- think that was right, but since I'm no metallurgist I thought it'd be best to let Thomas explain why he thought that. Thomas punted to Quenchcrack, who seems to say that both forging *and* thermal cycling can reduce grain size, apparently even in very simple steels without manganese or other alloying elements. That makes sense to me. So I think we're done.

Matt B - Tuesday, 08/21/07 13:22:53 EDT

Alan, by the way: I don't mean to blow off your slag stringer theory. I just don't know enough to have a worthwhile opinion on the merits. Perhaps Bob will.

Matt B - Tuesday, 08/21/07 14:44:29 EDT

I am a blacksmith, 66 yrs young, and have a huge, 8 1/4 inch wide jaws, post vise that I have actually never put into service and wondered if anyone has ever seen one this large, I have not.
Probably weighs around 200 lbs. never weighed it.
Thanks
Dave

Dave Plowman - Tuesday, 08/21/07 15:54:39 EDT

I think that we still have a definition problem since Huntsman steels are about a century pre-bessemer (the commercialization thereof).

Shear steels are made by carburizing wrought iron into blister steel and refining by repeated forging and welding.

Crucible steels (Huntsman process) were made by taking blister steel and melting it so it loses the ferrous silicate content of shear steel (floats to the top as slag...) and becomes a more uniform product

And as Alan has mentioned local ore content can affect final alloy content---*BUT* production methods can greatly affect uptake, mainly dependent on temperature. I know of a study that showed that comparing bloomery produced and indirect produced wrought iron from the same ore body the indirect method metal had close to twice as much Mn in it as the lower temp smelted bloomery method.

It would be interesting to do a simple experiment on thermal cycling to see if it does a good job of grain reduction on early steels. I can provide a piece of 1828 steel and some plain wrought iron including a piece I helped smelt from ore using a Y1K short stack bloomery. Anybody know a student in MatSci that needs a research project?

I would suggest overheating the samples to get large grain growth, polish, etch and photo. Then thermal cycle a number of times and polish, etch and photo and look at the relative change for each sample.

Thomas

Thomas P - Tuesday, 08/21/07 16:08:31 EDT

Thomas, I wouldn't be all that surprised if someone has already done what you're proposing, or at least something very close. What we might need, to start with, is someone with access to some of the research databases that taunt me when I run Google searches on metallurgical questions. You know: the ones that give you a promising abstract, but won't let you read the article unless you fork over $30 or are working in a university library?

Matt B - Tuesday, 08/21/07 18:07:38 EDT

I did not say forging reduced grain size. It must be incorporated into a process that produces austenite, crushes the austenite, then cools fast enough to form ferrite within the crushed austenite grains. Forging alone only flattens the austenite grains but does not increase the grain boundaries. This is like squashing chicken wire: the length of wire around each hole is the same whether it is flat or in a normal hexagonal shape. By cooling rapidly to form f