Matt Bower

Where's the slag coming from?

A lot of it's probably coming from the charcoal ash, no?

Jesus, what sort of surface is that little furnace built on? And can you give rough dimensions? (I realize it's flexible; I'm just trying to get a sense of the scale of that one.)

For the record, I've never made a pneumatic chisel of any kind, and I've never worked with the steels that I'm about to mention. Since no one else has chimed, I'll offer a couple thoughts. But I hope someone more knowledgeable than me will eventually respond.

Generally speaking, for your application I think you're going to want a shock resistant steel like S2, S5 or S7, all of which which are very tough at reasonably high hardnesses. I believe a lot of commercial pneumatic impact tools are made from S2 or S5. Unfortunately, finding S2 or S5 as bar stock may be difficult. I've never seen a source for either. S7 is readily available in square and round, in sizes that would work for you. Try onlinemetals.com or mcmaster.com, just to name two. (Neither one of those is especially cheap; you may be able to find better deals just by googling S7 tool steel.)

I haven't worked with S7 myself. Bob Engnath has some heat treating recommendations: http://www.engnath.com/public/harden.htm I imagine you'll want to temper softer than he suggests. He's talking knives; you're talking heavy duty impact tools. I don't have a specific tempering recommendation, though. In The Complete Modern Blacksmith (which is a book you should definitely consider picking up, by the way -- I've found it in the store at Borders) Alexander Weygers describes the forging of various hand tools for stonecarving, and he discusses heat treatment. He's using simpler steels than the shock-resistant steels I mentioned, but his suggestions will probably get you into the ballpark. I don't have my copy of the book handy at the moment, so I can't relay his specific recommendations.

3. Get a stick welder, and weld "porter" stubs onto your stock. For example, weld a 1/2" round stub onto your flat bar. The round or square tongs will grip it just fine. Or forge a stub before cutting off, just like they did in the old days. Be careful of high carbon or tool steel. You have to trust your welds, but when they fail, they usually give you a little warning.

I bought a pair of the OC goosneck tongs for RR spikes (5/8" square) from Blacksmith Depot. RR spikes are easy to come by for free. They make functional porter stubs. It's not a universal solution to all problems, but Eric is right that you can do a lot of work with one set of tongs that way.

Look here

 

They are not used beat up tongs, but they are good, and not expensive.

 

I'd suggest learning to make tongs yourself. It is not terribly complicated. But Tom tongs are relatively inexpensive, and good.

I missed a chance to buy several sets of Tom tongs on eBay a while back, very cheap. I made the mistake of telling the guy that he had listed them in the wrong category. Then I forgot to bid on the ones that were listed. The auction ended, he relisted them where I told him to, and suddenly tongs that he couldn't sell for $5 each were going for several times that. D'oh.

I haven't created any exciting chemical reactions lately, but I want to compliment you on your taste in beer, Peter.

Schwocker, aye!

I try to counterbend, but I rarely get it entirely right. I make up the difference using a wooden "mallet" (more like a club) with a stump for an anvil. The wood is gentler on the edge.

My anvil is "nailed" to its stump with RR spikes. No need to reinvent the wheel.

Your RR track will do for now, but it's not a terribly satisfactory anvil. 32 pounds isn't that heavy, and most of the mass won't be under your hammer. It'll get you started, but you'll waste an awful lot of energy. Keep looking for something better.

Like I said, you should be able to make your own kit for a lot less. The concept is pretty simple; it'll just take a lot of experimentation to get it right.

It's basically a matter of carburizing a very clean steel part in an oxygen-free container at above critical temperature, then dumping the entire contents of the container into water with air bubbling through it. That's a very simple explanation, and in actual fact it's tricky to get right. You can buy a kit from Brownells: http://www.brownells.com/aspx/NS/store/Pro...HARDENING%20KIT

That's the way I'd go if I were serious about it. But you should be able to make the whole setup yourself, if you prefer.

It is an attractive effect, but it's not super-durable.

Also, the salt in the used cooking oil may help with the quench according to info from Wayne Goddard. Good luck!

?? I really doubt it. I can understand the reasoning -- salt added to water disrupts the vapor jacket and speeds up the quench, so why not salt added to oil? But I think there's a good answer to that "why not?": salt is insoluble in oil. At least table salt is. I don't know what other kind of salt might be added to cooking oil.

Unless you plan to start out forging crankshafts for locomotive engines, you are about 2 orders of magnitude too large.

100 times too large? Maybe not quite that much. But yes, a 55 gallon drum is way too big.

http://www.dfoggknives.com/forge.htm

They're good for welding; I'm not sure how flexible a design it is for other things.

The most common recommendation for distilling vinegar is to freeze it. The water will freeze first. When you have ice crystals in liquid, pour off the liquid -- it's a more concentrated form of acetic acid.

I've read that boiling won't work. Something about azeotropes. That's not something I covered in chemistry way back when, so I offer no opinion about whether it's correct or not.

I-beam will not work well at all. Remember: an anvil needs to be rigid and put as much mass as possible under the hammer. I-beam doesn't meet either one of those criteria. You can do better than that. Look around a little.

Your railroad track question suggests that you're not stuck in the mindset an anvil has to look like a London pattern anvil. That's good, because it doesn't. Howard is exactly right: any heavy, rigid piece of steel will do.

RR track is not ideal, at least if it's used in the usual fashion where it lies flat and you work on the top of the rail. The web makes it springy, and that arrangement puts little mass under the hammer. It will work, but you'll waste a lot of energy. Mounting the track on end is much better, but it gives you a very small work surface. Something along the lines of what Tim Lively does will give you good rigidity and mass under the hammer, and a reasonable working surface: http://www.livelyknives.com/basicsetup.htm

Really, though, it all comes down to what you can find. Use your imagination. I saw a pic of a guy who went to the scrap yard and found a big, discarded hydraulic breaker from an excavator. He said it weighed probably 300 pounds, and I'd guess it was probably 5" in diameter. He half-buried that in the ground, upright, and used it as his anvil. For bladesmithing purposes that's probably superior to a 500 pound London pattern anvil (I'll bet it's high quality, heat-treated steel, too), and he got the thing for a song.

Oops.

Thanks, Ken, that helps a lot. I had totally missed the fact that the core of each anvil is a length of tube.

Friday I bought a 20-ton air/hydraulic jack at HF, and Saturday I cut up some 2.5" square tubing that I had lying around. Turns out I'm going to need some more tubing in addition to some other materials. On that note, are any of you folks willing to post dimensions on the stock you used for your top and bottom anvils? TA Toler's original top anvil was very heavy and solid, but it looks like some of you have moved away from that in later versions. (Ken, it looks to me like your top anvil is more or less a square tube welded up out of flat bar. Am I right about that?)

My natural inclination with most things is to seriously overbuild, but I'm going to have to buy some of the materials and overbuilding costs extra. So it might save me a little money to know what's actually working for others.

I tried a multi-turn toilet valve, which I believe is a crude form of needle valve. It doesn't work very well. Definitely go with a good quality needle valve.

Some pottery supply stores carry ceramic wool. But an awful lot of people can't find pottery supply stores near them. (I guess I'm just lucky. I have two within 20 minutes' or so driving distance.)

That's great, Chris. I've been there. I wish I had video of some of my more exciting moments with the oil burner. I honestly can't believe the neighbors have never called the FD on me.

By the way, that was a real rich mix you had going there. It won't produce all that soot when it's burning neutral.

Yes, a nearly out of control oil burner is pretty intimidating. The first time I fired mine up I went pretty heavy on both oil and air, and standing directly in front of one of the doors at a range of fully six feet was extremely uncomfortable. I'm not kidding when I tell folks that I'm pretty sure it could destroy itself.

I'm not a professional in this field, and really barely even qualify as an amateur. So I don't have as large a personal stake in this stuff as many of you folks do. That said, I'd like to ask a few questions as a sort of devil's advocate.

(1) If information is freely shared, does failure to give credit to the inventor really constitute "stealing", so long as the user isn't claiming that he (or she) is the inventor?

(2) In the same vein: at what point does the supposed obligation to give credit to the inventor terminate? Here's what I mean: essentially every useful idea was presumably, at one point in history, new and original. But eventually ideas become so widespread and widely understood that they're essentially taken for granted. And even if history recalls the details of their development, it's certainly not common practice to perpetually give credit to the inventor each time the idea is used. I.e., you're probably not going to find anything in your car's owner's manual about Nikolaus Otto, even though he invented the internal combustion engine. And I tend to think that's OK. So where, exactly, do we draw the line between that situation and a less-widespread (but still publicly shared) idea that was developed a couple years ago, rather than 150+ years ago?

(3) If I, a newcome to a field, run across a technique that seems to be widely used, without realizing that it was "stolen" (in the sense that folks seem to be using that word here) from its inventor a few years before, am I somehow morally culpable for using it without crediting the inventor?

This is probably a silly question but oh well. I just built a coal forge out of an old grill and was wondering why take time to make chacoal from wood when I could just burn the wood and use those coals. Is there a heat difference? Does it burn longer? Any help is greatly appreciated.

 

Thanks,

Doug

Charcoal's definitely cleaner and, unless I'm mistaken, hotter. I believe the volatiles in wood -- water and some other stuff, which are cooked off during the coaling process -- create an overall lower temperature flame compared to burning pure carbon (charcoal).

That doesn't mean that wood won't work.