WELCOME to the anvilfire Guru's Den - V. 3.3

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 March 16 - 23, 2012 on the Guru's Den
[ THE - GURUS | ABOUT THIS PAGE | Getting Started in Blacksmithing ]

Spontaneous Combustion : This happens in all kinds of materials under various conditions.

Sawmills used to pile huge stacks of sawdust as waste and they would often spontaneously catch due to biological action. Adding water increases the problem if its not enough to thoroughly soak the entirety. Today sawdust is much less of a problem because it is in high demand for making chipboard.

Chips and dust from numerous metals produce heat as they naturally oxidize. Most will take oxygen from water releasing hydrogen and making things worse. So you generally don't put water on a metal fire. Zirconium is one of the worst for this but is mostly used in the nuclear industry.

Consider that rust (red iron oxide) is used as the oxidizer in Thermit when mixed with powdered aluminium. You can end up with both materials in a dust collection system from a belt grinder or in saw swarf.

So it is not just phosphorus and sodium that burn rapidly. Many metals do under the right condition.

The "FIFTH Element" in Chinese alchemy is metal and for good reason.

Chemistry is not just for geeks, its knowledge you need to keep safe in the shop.
   - guru - Friday, 03/16/12 00:39:41 EDT

Chemical Heat : Many chemical reactions create heat and most people do not realize it.

Diluting acid with water creates heat. Add water to undiluted acid and the action is violent (explosive). SO, the rule is to always slowly add acid to water. The larger volume of water provides cooling and disperses the acid.

Epoxy creates heat when it hardens. You do not notice it in small amounts. But mix a full can of resin and it will create enough heat to set the label on the can on fire. As the volume of a casting is increased the amount of hardener added must be reduced to slow the reaction and prevent overheating.

Polyester resin in Bondo does the same. We once made a hand grip shifter knob by covering a small knob with a huge gob of the putty while my friend held it with his hand to make the shape. As it was setting I asked if it was getting hot. My friend said, "What do mean hot? hot Hot HOT *HOT*!!!. . . I knew that much would not get too hot but it was uncomfortable. We pealed his fingers out just as the bondo had become rubber hard. Made a nice custom grip but only fit one person with relatively large hands.

Plaster makes heat when curing and is very temperature sensitive. Minerals in the water used to mix it can accelerate the curing and combined with hot weather can result in plaster that you cannot mix fast enough before it starts to cure. It gets hot enough to produce steam in many cases.

A much lesser known thermal reaction is from curing concrete. When large masses are poured it gets very hot. When we poured a section of dam about 4 feet thick there was a flood and flowing water covered the curing concrete for several days. When the water dropped and we removed the forms the wood was uncomfortably hot to handle and steam wafted off the freshly exposed concrete for hours afterward.

A good rule is, If it hardens (cures) by mixing two ingredients (including adding water), it creates heat that needs to be considered in many cases.
   - guru - Friday, 03/16/12 01:27:09 EDT

Spontaneous Combustion : Dont forget,
Of special interest to us Smiths is, coal and charcoal is a well known Spontaneous Combuster.
(Maybe not if you name is Hank Hill who heats exclusively by propane)
Some coal varieties combust easier than others, and its normally only in large volumes.
Its still good practice for storage as they say in a dry cool location. The worst scenario is being damp.

Actually I am guilty of about the worst possible storage as I have coal bags stacked beside (Not touching the building) the shop, under a black tarp. Mostly for the tarp keeps UV radiation off the cheap 'poly bags which otherwise self destruct within a couple weeks. But it also traps moisture & heat both absorbed from the sun and whatever heat generated by the self oxiditaion of the coal.
With that said, were it to ignite, It would be a SLOW burning event and be easily noticed. About the worst scenario is losing coal that I paid for at about $800/ton !

Its not unknown for a railcar to ignite, even the Titanic reportedly had a coal bunker on fire as it left England.

Carbon is wonderful stuff!
   - Sven - Friday, 03/16/12 02:32:33 EDT

Epoxy : DO NOT reduce the ammount of hardener to slow the setting of epoxy. Use the proper hardner for the temperature range and section thickness You are working with.

Unlike pollyester & vinilester resins, epoxy requires the proper ammount of hardner and resin to cure properly and achive the published strength & hardness. Time or temperature will not overcome an improper mixture.

Epoxy must be mixed thoroughly to cure properly. In this regard as well it is less forgiving than pollyester or vinilester resins.
   - Dave Boyer - Friday, 03/16/12 02:36:00 EDT

Resins and resins : Back when I was working with a lot of epoxy (1960's) the hardener was pure, a thin clear liquid. You could vary the amount by quite a bit to control the rate of hardening. We were doing fiberglass layup and never had a hardening problem. Later we used quite a bit of Devcon metal filled epoxy for molding and had to be careful with thick sections. Same hardener. It was a tad tricky since the ratios were a few drops per cup of resin. A little 2" long tube (about 10cc) came with a quart of resin and was more than what was needed.

Most modern epoxy is equal part stuff with the hardener mixed with inert epoxy filler. I've used very little that I was satisfied with other than the stuff made for bolt and stud anchoring. I suspect the "professional" products are much better than the stuff you buy off the shelf these days.

I've seen a lot more problems with the bondo type products (polyester?). When we first started using it the hardener was a similar clear thin liquid and hard to get the right proportions. The directions said something a "X number of drops per golf ball sized lump". Now. . TRY to equate a tapered gob on a board to a golf ball volume. . This early stuff always hardened well and was never gummy after 12 to 24 hours. Then they came out with the colored paste hardener and the putty never got as hard even though it was easier to mix (now it was a 3" strip per golf ball). Even though the pure liquid hardener was more difficult to judge when it was mixed it tended to diffuse into the mix and not leave any gumminess. The newer stuff has never been as hard but it may be due to manufacturers reducing the proportions of resin to fill. I've mixed gallons of this stuff in a few days and reduced as much as 50% to filings and dust in the following days. I used to be able to mix any size batch and determine the setting time as needed from 10 minutes to just a couple. I never had a batch fail but I've seen a lot that did. Lots of personal experience there.

For many years body filler had marble dust as the fill. That became scarce due to the popularity of the product so they changed to powdered glass. I think the old stuff was better but there is no going back and no choice in the market that I've seen.

After building one Soap Box racer with epoxy and fibreglass and all the work associated with finishing the nasty stuff I built my next two cars using body filler and glass cloth over wood. To do this you have to mix quart sized batches FAST and still have a minimum 5 minute working time. It worked (held up for over 20 years) and was much easier to finish. I'm sure it was not as strong as epoxy but in this application (over solid laminated wood) the result was the same. It held the wood together and let us put on a perfect race car finish.
   - guru - Friday, 03/16/12 03:43:10 EDT

Farrier's anvil : If I want a farrier's anvil and have only a standard blacsmith's one could I make a saddle to slip over the face which has clips welded to it? Do any of the farriers on the site have any observations on the subject?
   philip in china - Friday, 03/16/12 03:49:12 EDT

Farriers Anvils: Phillip, From a forging stand point I do not see a saddle being attached well enough for the purpose.

Originally what we call the standard English pattern or London anvil WAS a farrier's anvil. The size and shape of the horn, the narrow face and the pritchel hole are ALL elements added to make the anvil better for producing horseshoes. Since the industrial revolution coincided with the peak of the horse drawn era all anvils were rooted in the farriers anvil. Prior to that most anvils did not have horns or punching holes.

While a few makers made slightly modified anvils for the farrier the modern "Farriers" anvil did not come about until the 1960's. These had the added clip horn bulge, a narrow face and double pritchell hole. But their biggest difference was their extremely narrow waist and light base reducing their weight for their length to half or less of a blacksmiths forging anvil. POrtability was more important than forging efficiency. Since then there has been a long line of trendy farrier's anvils with various gimmicky features. These have include:
  • Added pritchel holes.
  • Single and double clip horns.
  • V-groove fullering swage in face.
  • Turning cams (two pins to bend shoes between - on the side or end of the heel).
  • Large round chambered "hardy hole" for bending - required a special hardy.
  • Aluminium base to reduce weight.
  • Hollow to reduce weight.
When Hay-Budden made special order farrier's anvils they just took a standard anvil and modified it.
Hay-Budden Farrier's Anvil
Hay-Budden Farrier's Anvil

The above was a Hay-Budden custom farrier's anvil. I owned this one and have seen others like it. It is a two hundred pound anvil with bolt holes in the base, an extra pritchel hole and one side of the table ground off. Most prototype farrier's anvils start as a production anvil then parts are welded on AND/OR reshaped by grinding. The first side cams were welded on. If you need a "clip horn" it looks like you could just round the heel of the anvil.

Many of these features are personal preferences of a particular school of shoeing. They would make their special anvils and the students would have to buy them from the school. Some of the features have been developed for shoeing competitions where speed is of the utmost importance.

   - guru - Friday, 03/16/12 11:59:50 EDT

Phillip, if you have a modern anvil why not just weld on a clip if you need it?

I know of several smiths how have welded on a shelf like for a coachmaker's anvil
   Thomas P - Friday, 03/16/12 13:28:25 EDT

Oily rags : The ones I was referring to are, in fact, rags soaked with polymerizing oils from paints and other finishes. They have to be dried. Oil-soaked rags I simply dispose of as they remain a convenient point of combustion for errant sparks and I have a limitless supply of fresh rags. Otherwise they should be stored in a closed, airtight container as noted by others. I have safety cans for that purpose but don't generally use them. I do use the safety cans for storing dirty solvents.
   Rich Waugh - Friday, 03/16/12 14:22:10 EDT

Fiberglas resins : Probably 90% of the resins used with fiberglass are polyester resins, not epoxy resins. You can vary the amount of hardener to affect curing time on large sections with that stuff. As Dave Boyer notes, however, the true epoxy resins like the West System Epoxy Resin used by a number of boat builders, has a range of different hardeners for different curing rates and should always be mixed to the recommended ratio.

For most of us, the easy, (though not absolutely infallible), way to tell polyester resin from epoxy resin is by the color. Polyester resins are usually tinted a pale amber, pink or purple color and epoxy resin is almost always gin clear. The usual hardener for polyester resins is a benzoyl peroxide compound that acts as a catalyst/accelerator while the epoxy hardener is a polyamine component of the finished epoxy compound. Thus, the shelf life of true epoxies is usually much longer than the polyester resins that ultimately begin to harden on their own, albeit slowly.
   Rich Waugh - Friday, 03/16/12 14:40:56 EDT

Farrier's Anvil : If you want a farrier's anvil mostly for the clip horn, I'd just weld one on a regular anvil or select one corner of the heel and radius it to about the diameter of a quarter and be done with it. Alternately, you could make a clip anvil to fit in the hardy hole and have a sturdy enough solution that doesn't deface the anvil.

Not that I'm intrinsically opposed to modifying an anvil - I'm planning to weld a shelf on my big Nimba. :-)

These days, specialized farrier's anvils have narrow faces, wasp waists, clip horns, multiple pritchel holes, turning cams cut into the heel, exaggerated turned-up horns, and possibly other features I haven't seen yet. I assume they're very handy for farriers, but the ones I've seen would not be optimal for general forging.
   Rich Waugh - Friday, 03/16/12 14:49:16 EDT

Many smiths start as farriers and never work on anything except light farrier's anvils. When they work on their first forging anvil they are often amazed at how much more solid and efficient they are. A 125 pound farriers anvil is a big long springy thing. A good London pattern anvil of the same weight is less than half as long and 2 to 3 times more effective due to all the mass being in the middle.
   - guru - Friday, 03/16/12 15:38:13 EDT

I tend to toss iffy rags into the firepot of my coal forge. If they catch on fire they can't harm anything...
   Thomas P - Friday, 03/16/12 19:31:07 EDT

I burn all of my oily rags in the coal forge same day as made oily. Safer.
   ptree - Friday, 03/16/12 20:52:50 EDT

I was going to say that when I was burning coal that the shop was pretty empty of anything that possibly could be used to start a fire OR any trash that was safe to incinerate in the forge.
   - guru - Friday, 03/16/12 22:31:29 EDT

Resins : A few drops of clear liquid to a cup of resin sounds like MEK-P [methel ethel keytone peroxide] and pollyester resin. The cream hardener is benzonol peroxide. Pollyester resins and vinilester resins in commercial use are hardened with MEK-P.

Epoxies are a whole different family chemicly. The 5 minute cure formulas do not achieve the same properties as the others with 30-45 minutes open time [when the proper hardener is used for the temperature and section] and full cure in a day or several days. The equal part formulas have filler added to the hardner as well as the resin to make mixing easy.
   - Dave Boyer - Friday, 03/16/12 23:38:07 EDT

Body filler : In My youth, the filler material was powdered gypsum. There were marine formulas that had glass microspheres, as these hold up better when immersed in water long term. The gypsum is still used to manufacture "cultured marble" counter tops. I don't think I have used any Bondo since the early '80s.
   - Dave Boyer - Friday, 03/16/12 23:46:52 EDT

Clips on horseshoes : The clip horn, the little projection at the base of a farriers' anvil, is not liked too much by farriers. If the shoe is held at at various angles using the clip horn, by the time the clip is drawn, it makes a crescent shaped depression on the foot surface of the shoe. You wind up with an odd blind hole where there should be solid steel, and that is the surface that goes to the plantar surface of the hoof wall. We say that it "guts out" the edge of the shoe's foot surface. That is poor shoeing practice.

When I was shoeing, I started with the clip horn, but was soon shown by my mentor, Al Kremen, that a better job could be done on the off edge of the anvil using the ball of a ball peen hammer. You would pick a relatively sharp edge as opposed to the radiused edge nearer the horn.
The shoe is held at a 45 degree angle and approximately 3/16" above the anvil edge. With the ball, you begin your drawing blows hitting fair and square, some of the blows similar to half face blows. The clip will begin to thin and form over the anvil face and as it does, you slowly lower the shoe angle as you work until as you finish drawing, the shoe is vertical. The clip should be standing up at least twice as high as the shoe thickness. You can dress some of your peen marks with the hammer face. Sometimes, finish shaping can be done with a hot file or cold file. The clip will be thicker at the base than at the tip.

In the UK, the farriers often start the clip with a bob punch. You could use a 1 1/2 pound ball peen with an annealed face, thus turning it into a top tool. The face would become the striking head. An edge of the shoe is often held over the corner of the hardy hole, ground surface upward, and the bob punch (ball) is driven down in that corner. This forms a starting "bump" protruding a little toward the foot surface. The shoe is then turned over and the clip finished over the far anvil edge, as described above. Some farriers prefer a slightly oval bob punch to a ball shaped one.

It takes practice to draw a nice clip, especially between nail holes without boogering up the nail holes.

What are clips? These fairly thin projections are visible after the horse is shod. If there is daylight between clip and hoof wall after nailing, not a big deal. With the foot on the ground, just tap the clips so that they bend till they're tight to the wall.
The mail purpose of clips is to keep the shoe from shifting on the foot, especially on athletic horses, such as hunters and jumpers. Even though the shoe is nailed and clinched, it may shift to one side or become twisted.
   Frank Turley - Saturday, 03/17/12 00:35:18 EDT

Clips : Great description of the process, Frank. I think I could probably make one from that description alone - as long as I didn't have to have anythig to do with the horse itself. (grin)
   Rich Waugh - Saturday, 03/17/12 03:04:40 EDT

We use about 50-60 gallons of polyester body filler a month at the factory in a QA process. Since we try for the least expensive that will serve, I have looked at many many brands and types. Seems there are 3 major makers with many brands and flavors each. The MSDS's for the lot are near identical. All polyester with benzoil peroxide creme hardener, all are either limestone gypsum or glass micro-sphere filled, or some combo of the three. Usually if you see "Lite, Light" or something similar in the brand name they have micro-spheres in the mix.
Not long ago, I was able to make a suggestion to change brand and vendor and reduce the price about $7 a gallon. No change in performance in our case.
   ptree - Saturday, 03/17/12 09:31:57 EDT

Metal Powders : Even reduced iron powder can be explosive in the right condition - one of our competitors Hoeganaes Corp. had 2 major incidences last year at their Galatin Tn plant that resulted in loss of life for employees and temporary plant shutdown - a google search should turn up information. We keep our plant cleaner, (much cleaner since the accident in Tn), so have not had that problem.

When working at Elkem Metals in Marietta, OH we milled electrolytic manganese and electrolytic chromium into powders for further processing. We used ball mills inerted with nitrogen - we did have a small puff in the electrolytic chromium ball mill in the out take area of the mill while I was there. They'd been running it for about 20 years without issue at that point. They immediately shut the mill down and investigated to determine why they had an incident of spontaneous combustion, and the mill stayed down until the reason was determined, corrective actions were taken, and their efficacy verified - the only place I've ever worked that was that committed to safety.
Turned out that the mill in the right conditions with the flow of nitrogen they had and its entry points left a small area that under just the right conditions was on the edge of the explosive limit. Adding an additional nitrogen inlet and increasing flow solved the problem.

Also, standard fire fighting for most of the powders we processed there was either cover with sand, use a special dry fire fighting agent to put it out, or just get everyone away and let it burn itself out. The proper agent depended on the material catching fire - chromium was one of the "let it burn out" materials.
   - Gavainh - Sunday, 03/18/12 01:55:33 EDT

The metals fires I've seen moved so fast that the RUN and let it burn advice is the best.

Sand buckets are good, cheap and reliable for putting out many types of fires. You can "recharge" and maintain them yourself. If you have fire extinguishers hanging in your shop there probably should be a sand bucket hanging next to each one as well.

Teen Age Stupidity. . . When we were 16 or 17 my best friend had a big old Austin Heally 3000 and no budget for stock parts. . . It needed exhaust pipes so he fitted two straight pieces of 2-1/4" exhaust pipe coupled to the manifold with some flex pipe. Now . . . not only were these pipes without mufflers they were physically straight. The sound was like it was amplified by a bull horn inside a big tank. If you were into LOUD exhausts this was the ultimate.

We tried to tone it down by packing some steel wool in the pipe held in place with some wire. This reduced the sound by about 20% if you did not stomp on it. So off he went home. On the way he was being followed by some drunk red-necks tailgating him. So he shifted down and punched it. About 3 seconds later a couple big white fire balls exploded from the exhaust like signal flares. This was even more impressive due to being on a dark stretch of road along with the sudden explosion of sound! Good-by red-necks. . .

Then there was the rubber band shock absorbers. . . But that is another story.
   - guru - Sunday, 03/18/12 12:37:37 EDT

Sand Buckets: just watch out for water and cats! Water makes them dangerous for certain types of fires that can crack the water for fuel or even worse if the contents freeze solid during the winter.

Cats are more a smell issue...
   Thomas P - Sunday, 03/18/12 15:57:38 EDT

Fire buckets : To be entirely "correct" a fire bucket should have a semi hemisphercial bottom. (however I seen plenty with flat bottoms)As then it cant stand upright on its own, that prevents it being hijacked to being used on other jobs like floor mopping etc.
Also the reason they are normally seen hanging on a hook, Because they cant stand upright themselves.
Also adding to the comment of Thomas P, Along with certian fires striping oxygen off the sand, Damp sand can flash to steam and blast hot materials & further spread a fire.
Sand is also useful to thrown upon a fuel or oil spill as it absorbs the liquid from spreading & reducing the loose vapours to prevent an ignition.
   - Sven - Sunday, 03/18/12 18:20:46 EDT

Fire buckets : Interestingly, I mentioned this to my friend from Ukraine.
He pointed out their firebuckets are just made as cones with a familiar hoop handle.
As a cone shape they cant be hijacked to other bucket tasks, and be filled more quickly if dipping into a water source if tied to a rope if need be.
Turns out like many otherwise simple things,
There is alot more science to it than the first impression indicates.
   - Sven - Sunday, 03/18/12 21:45:16 EDT

Fire Cats; Clips; Metal Fires : Thomas: I have never tried to put out a fire with a cat; but since the wif has a new cat I'm certainly willing to try. Do you try to beat the fire out with the cat, or just toss the cat on the fire? I guess the burned fur does smell bad afterwards; but at least it's a worthy use for the cat. ;-)

(Just kidding; honest! Merlin is a very nice cat. Still I find the concept interesting. :-)

Frank; just to confuse things, when I first got interested in blacksmithing I had the reprint of the 19th century "Practical Blacksmithing" by M.T. Richardson and some old farrier catalogs from a friend. Between the "clips" on horseshoes and the various "clips" in Richardson's book (whch may refer to the equivalents of U-bolts, staples or collars) I was a very confused beginner!

Metal fires: And then there are those occasional cases where someone grinds aluminum on a grinding wheel, and then goes back to grinding rusty iron, thus providing fuel, oxidizer and ignition source all at the same place for do-it-yourself thermite incineration (or maybe just melting a whole though the floor)! Or, at least, so I have been told! :-)

A lovely climatic spring day on the banks of the lower Potomac. We're scraping the ship's bottom and cleaning and sorting tools for the spring fix-up.

Go viking: www.longshipco.org
   Bruce Blackistone (Atli) - Sunday, 03/18/12 22:49:30 EDT

Fire / Sand Buckets : Sven, Painting them bright red with the word "FIRE" on them is all they should need but people are people. . .

Yes they need to hang at a convenient height to keep them dry and keep out cats. I have also seen them labeled "NO BUTTS" due to people putting cigarettes in them. . .
   - guru - Sunday, 03/18/12 22:52:07 EDT

anvilfire X1 Power Hammer : FINALLY! After 4 years we have finished the anvilfire X1 power hammers. One is complete and the other needs a final modification before paint and assembly. Thanks to all who have made or worked on parts -- Sandy Wilson, Dale Poulliot, Rich Waugh, Jeff Moyle, Dave Baker (the lions share) and myself.

These hammers have a minimum amount of rotational non-working mass. The pitman and adjustable link are the only parts that move side to side. Being counterbalanced makes this a very stable machine that does not rock even though it only has a 16" wide base.

Above Dave is testing flaring stock side to side on the combo dies. We used Big-BLU dies and die holders. Next work session we will take some video.

Eventually I will make plans available. There will be yet a couple more changes. When I was designing these I was in the mind set of building two and sized many parts on what I could get two hammers out of stock lengths. I was also trying to keep the hammer as short as possible to fit into Dave's shop. While these were both good considerations at the time they were not good engineering reasons. The guides need to be a little longer and the frame even higher.

". . .I'm going to need a top nurse... not a doctor who will argue every little diagnosis with me. And they probably redesigned the whole sick bay too! I know engineers—they love to change things." Dr. Leonard McCoy (Bones), Star Trek: The Motion Picture
   - guru - Sunday, 03/18/12 23:39:00 EDT

Nice tire hammer
   - Dave Hammer - Monday, 03/19/12 00:01:39 EDT

Thanks! Next one I build will not have a tire. Flat belt clutch instead.
   - guru - Monday, 03/19/12 01:29:56 EDT

What is an easy demo that will hold the public's attention? (will be done in a park with basic tools)
   - Ed A. - Monday, 03/19/12 08:14:22 EDT

Public Demos :
Ed, I did public demos for many years and found that what you are making was not very important, it was how fast you could make it. Generally you are dealing with a walking, standing public that has little interest in details. What they want to see is hot iron, hammering hot iron and or bending hot iron. As soon as you stop to cut stock, measure, file or other non-forging work you have lost them.

I made lots of S-hooks from 1/4" (6-7mm) square and round. They are fast to heat up, demonstrate drawing, scrolling. bending and twisting. They are hard to mess up and relatively easy to sell.

I also made quite a few J-hooks but you lose your audience when you go to drill or hand punch screw holes.

Large nails or spikes are similar. However, I have found that demonstrating using a hardy in public can be VERY dangerous. If you use one be sure the piece you are cutting off is aimed AWAY from the public (toward the forge, back wall or absolutely unoccupied space). One blow too many while distracted and that nail can fly off like a bullet and strike someone or something. I made nails from precut lengths of small stock but this is difficult to head unless you use a header that grips the nail such as in a vise.

Always have your material pre-cut to length and lots of it. Stopping to cut stock is usually the end of the demo.

I also forged a LOT of leaves, mostly from 7/16" (11mm) square stock. Often I would make S-hooks with leaves on both ends. But I also forged leaves on larger and smaller stock. At my best I could forge a little 1/2" (13mm) wide leaf on 1/4" (6.35mm) round stock. These made pretty little S-hooks when the mid section was flattened a bit and twisted.

When making things from small stock 3/8" (10mm) or less it is best to work one piece at a time. It heats fast enough the public will wait and you do not burn up work. Larger pieces should be done two at a time.

Even though I am not a farrier I made lots of little decorative horse shoes. The only reason for this is that many audiences expect it. Parents have told their children, "We are going to go see a blacksmith making horse shoes." This varies with the audience and you may need to judge it on the fly. This is up to you.

A demo Dan Boone is famous for is tying a knot in a bar of steel. This is not hard to do in small stock (1/4" or 6mm round). However, it takes a long heat so you need a mature open fire or a gas forge.

I thought that scrolls with ball or long tapered ends would interest the public. I was wrong.

IF you are working a venue where the audience can sit down out of the weather and is close enough to see (but not too close) then you can do slightly more complicated pieces. But in these cases it helps to have two demonstrators to keep things moving. Remember that your audience is NOT other blacksmiths looking for details of technique but people that just want to see hot iron being mashed and bent (things they understand).
   - guru - Monday, 03/19/12 10:04:31 EDT

Demos : Like Jock, I try to do things that move very quickly - one-heat wonders, whenever possible. I've found that it helps a lot to do things that the audience can relate to in their own uses of metal goods. Down here, that's shutter hooks, pintle hinges, hooks and hasps. None of those are really one-heat wonders, so I pre-make each piece in all its steps from raw stock to finished piece, and mount them on a board or table. I have several almost-finished pieces so I can take a heat and do the finish forging, twisting or bending and produce a completed piece on the spot. Over the years I've sold hundreds of 14" shutter hooks so that is one item I often use for demos since I can toss the completed ones on the stock for sale shelf. I know they'll sell sooner or later. The same applies to pintle hinges. For the demo, I'll have the eye already rolled on some stock and forge the taper and bean end, or vice versa. Same for the pintles - I have stock prepare with either the eye or the tapered spike and finish up the other end at the demo.

My demos are done on a per-diem basis and I don't try to sell anything at them. If you're hoping to sell things, you must have a helper to handle the sales or you lose the crowd.

I carry with me a powerful neodymium magnet from a salvaged hard drive and use it as a volume control on the anvil. When things are slow I let the anvil ring like mad to "turn the tip", then stick it under the heel to shut the anvil up while I'm actually working. That way I can work without hearing protection and be able to hear questions.

If there's a bunch of kids at the demo, I'll make nails from 1/4" round stock. I can generally do these in one heat, but if a second is needed it's no problem as they heat in a few seconds. For safely cutting them on the hardy, I have a #10 tin can with part of the side cut away and a bit of sand in the bottom. I set that on the anvil so that the cut-off, if parted suddenly, is caught by the can, not the audience. 95% of the time I get it right and wring them off, but the can is for the other 5%. (grin) I have a dozen or more nails made up ahead of time so each one I make I give to the child watching most intently - if others look disappointed, I can give them one of the ready-mades. Never let a kid go away disappointed if you can avoid it!

I'll be demoing this Saturday 10 am to 4 pm at the St. George Village Botanical Gardens on St. Croix if you want to drop by and see how I do it. :-) http://www.sgvbg.org/art-in-the-garden-2
   Rich Waugh - Monday, 03/19/12 11:31:39 EDT

Round these parts chile peppers from black pipe is a nice demo with lots of room to use "the hottest peppers you'll ever see" and offer to let any heckler tast a glowing red one lines.

Use smaller pipe to speed them up and a good side arm fuller for tooling to pinch in the top and prep the stem.

I spray pain them bright red and sell them as "cat proof Christmas tree ornaments"---"unless you bought your cat a cutting torch for christmas..."

A lot of a good demo is the banter. Some folks could make watching steel rust a fun activity and some folks could make tossing bullion into a crowd boring.
   Thomas P - Monday, 03/19/12 13:42:23 EDT

demo's : I do lots of prep on anything that takes more than a heat or two. As noted banter is critical in keeping the audiance's attention. I keep a small board next to the anvil and I tell folks just cause the iron is black don't mean its cool, and then touch some black but still hot iron and get nice smoke.
I make coat hooks and bar-B-cue tools that have wizard faces in them. I have all the heavy tapers done at home on the PH.
I also make lots of small split crosses, and those I have precut.
   ptree - Monday, 03/19/12 14:23:07 EDT

Banter : I like to offer to "cure your iron deficiency"(sell them something) and that my work is "Dishwasher safe";)
   Willy Cunningham - Tuesday, 03/20/12 15:55:50 EDT

Door-Bolt Keepers : I am currently working on making a sliding door bolt and am having trouble forming keepers (staples?) that forms around the 3/8 bolt. I saw a picture of a "u-shaped tool like a bending fork to straddle the bump" in Ted Tuckers book Practical Projects for the Blacksmith. This seems like a really nice way to form those 90 degree bends around square stock. I am having a lot of trouble making one of these forks though. I have tried heating the end of the tool stock and pounding it over a piece of 3/8 sqaure. I have also tried splitting some stock down the center and bending the sides to shape. The problem is making it very exact so the bolt fits well in the lock. I feel like there is an obvious way to make one of these, but its not coming to me. Thanks,
   - Eric - Tuesday, 03/20/12 16:21:27 EDT

Eric, While what you are making may seem obvious to you it is not to me. Are these drive in staples, riveted keepers, shouldered and blind riveted? What is the cross section of the stock you are bending?

The best tool for making this type of thing is one that fits in a press or is used in a vise (you could also hit it with a hammer but that is hard on the tool.. Depending on the details you may need to make the internal form about 0.007" to .010" larger than the 3/8" bolt. That means starting with a piece larger than the bolt size and making it a little oversize. The edges of the outer forming parts need to have radiused edges so that the stock being bent rolls under those edges - you don't want them to bite in.
   - guru - Tuesday, 03/20/12 17:07:55 EDT

Look for clip making tooling as basically you are making a clip that then doesn't get the ends bent over.

I'd make them with my screwpress
   Thomas P - Tuesday, 03/20/12 18:05:49 EDT

Bolt keepers : You can see one style that I made at my site: www.turleyforge.com, clicking on 'gallery and biography page.' On that particular bolt, I used 1/8" thick strap for the keepers. I purchased two old furniture bolts years ago in New Orleans and the keepers were tenoned to the escutheon. I imagine the sheet metal of the keepers was hacksawed to create the tenons. You do not want an exact fit. You need a tiny bit of slop for the bolt to slide freely. If I were tenoning, before bradding them over, I would slip in a thin, steel spacer between bolt and keeper. I'd remove it after hammering.

I make my squared up keepers in an arc welded jig of mild steel. On a plate, I weld two square sectioned pieces a tad farther apart than the bolt and parallel to each other. In Eric's case, I'd drive a 3/8" square bar onto the hot sheet metal, the latter being at right angles to the parallel bars. The hot keeper sinks into the tool, giving right angle bends. Fine tune and file where necessary.

A typical Hispanic bolt is a barrel bolt of round cross section sliding through three cotter pins, and an escutcheon is not necessary. A decorative washer (concho) can be used with each cotter, thus acting like an escutcheon. The spacing of the cotter pins is done on site. They are driven through pilot holes in the wood and clinched, often double clinched. This latter method means to plier-bend maybe 1/8" to 3/16" of the emerged cotter tip to 90 degrees. Then bucking the circular portion, the clinches are hammer bent, the tip entering the wood. This gives the appearance of a staple when finished. The keepers are made by taking a length of round stock and flat tapering either end. The rounding center is bent into a U shape, dropped over a bolt sized hot rod, and squeezed closed in the vise. Careful measuring and test pieces may be in order.
   Frank Turley - Tuesday, 03/20/12 21:33:15 EDT

Ptree : We used to make the split crosses (Fredrich Cross) for the public at our Empire Mine State Park in Central Calif.
Now that the park is so PC (politically correct) we can't even forge them for ourselves. I used to really enjoy making the large ones.
   Carver Jake - Wednesday, 03/21/12 01:01:25 EDT

Ptree : We used to forge the split crosses (Fredrich Cross) for the public in the blacksmith shop at our Empire Mine State Park in Central California. But now the park is so politically correct we can't even make them for ourselves.
   Carver Jake - Wednesday, 03/21/12 01:08:58 EDT

Keepers : Frank, thanks, your response helps a lot. The photo of your bolt lock on your website is actually the one that inspired me to try this in the first place. Yours is extremely artistic and beautiful, yet simple. And also obviously functional and strong. I'm very glad to know how you put it together. I have seen lots of designs for various keepers, but I like your riveted ones the best. Did you have to create a counter sink for the handle rivet on the backside so it doesn't interfere with the sliding?
   - Eric - Wednesday, 03/21/12 09:57:34 EDT

Keepers : Yes. All rivets were countersunk, so that they didn't interfere with the woodwork mounting as well. An alternative would be to plug weld the shank stubs into their respective countersinks and to sand them flush.
   Frank Turley - Wednesday, 03/21/12 10:35:31 EDT

Riveted Square Bar Keepers :
When I have made that type on a one-off I've made them in the vise. I made the first bend in the vise, clamped a piece of stock in the vise and made the second bend, then the keeper and square bar in the vise with the thickness of the keeper above the jaws and tightened up the fit squaring the corners. After another heat the keeper and the bar was clamped in the vise upside down with the bar raised above the vise the thickness of the keeper material and the flanges bent outward. The loose keeper was then dressed and loosened up a bit working it over the bar on the anvil. One must be careful at this stage because the all you can do at this point is loosen the keeper by thinning it a bit.

I've also made this type of part in an anvil tool with an appropriate rectangular groove. The keeper is laid over the groove, then bent by driving into a piece of bar, the flanges being worked down as the bends are made. This is easier than a vise but not quite as high production as a press. The rectangular groove could be machined, or forged, but I arc welded pieces together to make mine.

Tools for a press are similar. They can be used in a large vise, fly press, arbor press, hydraulic press or even a punch press. Tools used in presses usually have stock stops to center the work piece. High production dies would have a second stage to punch the poles.

For countersinking rivets on the back of a plate a regular 120° drill bit makes a better rivet pocket than a countersink.
   - guru - Wednesday, 03/21/12 11:18:12 EDT

Bolt Keepers : I just finished a couple of heavy-duty sliding bolts for the Christiansted Fort. The keepers were forged from 5/16"x3/4 flat bar with square corners to fit a bolt 1" wide and 5/8" thick. These were vertical bolts for doors so they have a spring to keep the bolt under tension, which requires clearance and spring action. The keepers are tenoned into the back plate and riveted into countersunk slots.

Forging square corners close to each other with picky tolerances like that is a bit of a challenge, to say the least. I did a couple practice corners to determine the proper allowances so I could get them as close as possible. With the 5/16" stock there was some room for either stretching or upsetting the middle section to get the proper fit, though it turned out that I didn't need to do that.

I wouldn't normally go to the trouble of forging square corners on something like that, but these had to match an existing "historical" bolt so I had no choice.
   Rich Waugh - Wednesday, 03/21/12 11:21:07 EDT

Christiansted Fort Slide Bolts :

Bolt to replicate. Notice the poorly fitting sheet rock screws.

Bolt parts arranged prior to cutting tennon holes.

Detail of decorated keeper.

Lots of picky upset squared corners. Nice job. Will post larger images elsewhere.
   - guru - Wednesday, 03/21/12 12:49:45 EDT

Gurus tire hammer : Guru - Do you know the at rest total horizontal spring force at the linkage?
   Fred Connell - Wednesday, 03/21/12 18:05:13 EDT

X! springs : Fred, I am not sure. We have two leaves on each side from two different sets of springs. The original leaves that were the same thickness seemed too tight on our test assembly so we traded out the short leaf for a thinner one. I may try the heavier pairs when we assemble the X1a again. We have gotten better techniques for tensioning the springs. . .

The exact length of the cantilever and the sum of the two springs is tricky to determine. The force I calculated I needed was 1,000 pounds total at 7° sag but that is a bit sloppy and there were design changes since doing the calculations. I suspect it is more like 3,000 pounds or more from the amount of tensioning we had to do.

The spring sets were 1,250 and 650 pound at their full length of about 30". But the working length is 10" on our hammer which makes them much stiffer. We also re-arced the springs which has an effect.
   - guru - Wednesday, 03/21/12 21:59:48 EDT

Blacksmith in city : I would like to set up a small gas forge in my fenced backyard. The area I have in mind has no grass and is fenced on all sides. Not sure how loud this might be in the city or any zoning rules that I might be up against. Any tips, thoughts, experience or advice is greatly appreciated.
   Michael Joe - Wednesday, 03/21/12 22:29:34 EDT

Michael, Your best bet is to call yourself an "artist". Art studios are allowed in most residential districts. In older locations blacksmith shops, under the guise of a farrier's shop were also allow in residential neighborhoods. Check the zoning yourself. If you ask the zoning people then you will be on their radar. If they do not have a definition for "blacksmith shop" they will classify you under metalworking. . . However, you can generally get away with almost anything as a HOBBY. But make it a business then everyone can stick their nose into it.

Noise is a different issue. Gas forges do not make smoke but many have a distinctive roar and often make a good "whoomp" when they are fired up. Noise can be controlled somewhat by how you work and how your anvil is dampened OR the type of anvil you use. Steel faced cast iron anvils such as Fisher-Norris Eagle anvils and Vulcan anvils are very quiet compared to wrought or cast steel anvils. Other noises can be reduced by screens, walls, various dampening. Grinders such as angle grinders make a more grating, higher decibel noise than anything else in the shop.

Your best bet is to know your immediate neighbors and give them gifts of things you make at the forge. Do not work late at night or early Sundays (use common sense).

Generally a hobby blacksmith operation makes less noise than a leaf blower, less smoke than burning leaves BUT they are different noises. Angle grinders are loud an their noise carriers but table saws and skill saws are worse. Pay attention to the noises your neighbors or their kids make. I have neighbors who's kids race up and down our gravel road on loud 4-wheelers and motor cycles. They tear up the road, cause clouds of dust and so much noise you cannot talk outdoors many times. . . They would be unwise to complain about any noise I make. So I do not complain about theirs. . .

Many places have strict fire laws preventing open fires. A gas forge is fairly enclosed but someone may complain. IF a fire inspector comes to check be sure you are running it on low pressure to avoid dragon's breath. . . One loophole to open fires is an attended cooking fire. A pot of tea or roasting hot dogs in the forge makes it a cook stove. . .
   - guru - Thursday, 03/22/12 00:10:11 EDT

Michael your question has a strong location specific basis; but you have not provided a location---what country are you speaking from? If in the USA what part? Here in NM the fire laws can be quite stringent especially when coupled with air pollution laws in certain places.

I, luckily, live out in the country where the golden rule is "Don't annoy your neighbors". If you tend to be friendly and help them out they tend to support your oddities. When I lived in the city in Columbus Ohio I used a coal forge for 15 years with minimal issues in my city neighborhood. However a student of mine was soundly shut down after merely a couple of months in his neighborhood as he transgressed the rule mentioned above!
   ThomasP - Thursday, 03/22/12 11:29:59 EDT

Square bends close together : Rich Very nice job on the bolt.

After reading Lillico I have done some close right angles similar to your bolt by starting with heavier stock and using a side set either side of the bend and then forging out the ends. So you end up not bending the bar just drawing out everything that is not the bend. It means you don't have to upset for the corners.
   - JNewman - Thursday, 03/22/12 16:02:23 EDT

Rasp and File Making Rich sent me this video. Its pretty cool. Hand cutting rasps. Very interesting but I'd like to see some coarser rasps being cut. I've seen film of files being hand cut but rasps are different.
   - guru - Thursday, 03/22/12 23:02:05 EDT

Rivets : What would be the easiest way for a beginner to go about making rivets completely from scratch? I saw this pretty neat brace someone used in a vice where they clamped down some 3/4 inch rod and upset the ends. Also, would it be better to use a torch when making rivets or would a forge work just as well? I apologize in advance if I'm asking something that's already covered, I'm not crazy good at navigating websites.
   - Josh - Friday, 03/23/12 02:02:05 EDT

Rasp and File making : That is an amazing video. Where they are dipping the rasp into a liquid: is that a salt bath for heat treating?
   Milton Rodewald - Friday, 03/23/12 07:31:28 EDT

Rasp and File making : Milton, I am pretty sure that is a salt bath as they has to bead blast it off afterwards. I'll have to watch a couple more times.
   - guru - Friday, 03/23/12 12:02:51 EDT

RIVETS : Josh, There are many ways to make rivets and to rivet. Click the title link for one of several articles.

If you do not have a header a rivet can be made from a larger piece of stock. Say you need a 3/8" shank rivet for a pair of tongs. You could start with 1/2" bar (round or square) and carefully forge the shank like a tennon. This takes practiced hammer control to forge a clean shoulder working half on, half off the edge of the anvil. After forming the shank the rivet would be cut off the bar using a hardy or saw. The head could be finished when installing OR using a simple header with a hole in it.

You can also take a short heat on the end of a bar that is the rivet size and upset the end working off the edge or the anvil. Normally this is done with the end just beyond the edge of the anvil and striking the work toward you as you rotate it to keep the upset even. Quick fast blows are better than heavy blows.

In some cases you use a plain piece of round bar for the rivet. It is centered in the assembly and both ends upset at the same time OR one at a time using a torch to heat them. I usually start this process cold to assure the joint is tight and held in place. They I will heat each side, upset and finish.

Our second riveting demo shows a vice operated upsetting tool.

THEN. . there are commercial steel rivets. These are fast and efficient. The round heads are easy to convert to a rose head in a couple blows.
   - guru - Friday, 03/23/12 13:30:50 EDT

Erin Simmons has a demo where he shows how to make rivets from scratch. Since he got his start without any pre-made tools, he uses a technique that requires only bar stock, a hammer, and an anvil.

Starting with round stock (3/8" minimum for this technique, I think), he upsets it lightly. Then bends the end over about the diameter of the rod to a 90-degree angle. From there. He "hooks" the base of the rivet head (the side pointing away from the bent parent stock) and using half-faced blows, creates a lip on the edge. He then spends some time evening it up.

That's a bad description, I know, but perhaps someone else who knows the steps could help describe it?

I won his storyboard pieces in the raffle at the last CBA conference. I'll try to remember to photograph them and send them to the Guru so he can put them with the other rivet how-tos.
   Bajajoaquin - Friday, 03/23/12 16:00:48 EDT

Rivets: easiest way is to go buy 16 penny nails and clip them to length. (often used in modern medieval armour work...)
   ThomasP - Friday, 03/23/12 18:09:42 EDT

For large rivets I have used and seen hex head bolts, round head screws, and other fasteners. The fastener that looks the closest to a rivet is a button head machine screw. These look nice on assemblies where you cannot hide the bolt head and do not want to make something special.
   - guru - Friday, 03/23/12 18:49:54 EDT

Smiths in Greece : I'm in search of sons and daughters of Hephaestus. There is a possibility that I may take a trip of a life time to Greece, and would love to meet and visit the shops of any smiths that you all could put me in contact with. Athens and perhaps the Peloponnese.

If anyone has some metalworking contacts in Greece please let me know. Thank you.
   Judson Yaggy - Friday, 03/23/12 22:02:40 EDT

Judson, I sold a copy of Anvils in America to a fellow in Greece not long ago. Also, the owner or part owner of ArtisanIdeas.com lives in Italy and knows the area. More by mail.
   - guru - Friday, 03/23/12 22:35:28 EDT

Blacksmith Myths : As you know the Bi-annual ABANA Conference is going to be here in Rapid City, SD this July. Dr West from the metallurgy dept at the South Dakota School of Mines and Technology is doing a seminar on the science of blacksmithing. If you have aparticular blacksmithing myth you would like to have explored or busted, please send them to me so I can forward them to Dr West. Thanks
   Woody - Friday, 03/23/12 23:34:04 EDT

Woody : What kind of myths? You mean, like Apollo appearing before Vulcan to inform him that his wife is froggin' around with Mars? Or how about the horseshoe hanging heels down "so the luck continues to pour forth upon the forge." * Or how about some British shoes have four nails on the lateral side and three on the medial side? Lucky seven? One knowledgable smith says that the very surface of the hot scarfs is molten, and that is what makes the forge weld. I say horse pucky to that. How about the marks we sometimes see filed, especially on entrance hardware, typically a square having an "X" within and a dot in each of the four quadrants. I think it's a hex sign. Is it? Or is Dr. West more interested in dendritic structures, grain size, quenchants, and space lattices?

*"The Village Blacksmith" by Webber
   Frank Turley - Saturday, 03/24/12 00:46:18 EDT

[ Getting Started in Blacksmithing ]
Counter    Copyright © 2012 Jock Dempsey, www.anvilfire.com Cummulative_Arc GSC

Get anvilfire.com GEAR.

International Ceramics Products