MattBower

I don't have a lot of confidence in my spark testing abilities, but breaker bits are overwhelmingly something in the range of 1040. That's according to Grant Sarver, who used to make the things and got all his major competitors' products analyzed. And it corresponds to the results I got when I had a piece of a bit analyzed.

The stuff from the stove is likely over-charred, i.e., a substantial amount of the carbon has been burnt out. Direct charring in a fire is less controlled than a retort. The quality of charcoal that I used to get from just building a fire in my charcoal grill, then dousing it with water when I thought it was ready, was nowhere near as good as what I get from a top-lit drum, which probably isn't as good as what I'd get from a real retort. Used pallets are an almost inexhaustible supply of wood and can usually be had for free, at least where I am.

By the way, Wayne Coe's grinder looks very impressive, and it's a good deal for what it is. I know he has a lot of satisfied customers. It's still a lot of money for most hobbyists, though. http://www.waynecoeartistblacksmith.com/Grinders.html

I know a lot of people who've gotten by with the Grizzly until they could upgrade to something better, and who don't regret it. I am not a big stock removal guy, and my experience with belt grinders is fairly minimal, but I can tell you a few things. Longer belts wear longer and don't build up heat as fast. 2"x72" belts come in a wider variety of grit and belt options than just about anything else. The wide, horizontal sanders are made for wood and aren't designed to allow plunges. Also, the wider belts are more limiting if you want to do other than wide, flat surfaces. I think just about any maker I know would prefer the upright style Grizzly to the horizontal woodworker's sander. To give you a sense of the range of things, here are a few examples of real knifemaking grinders: http://www.youtube.c...h?v=7j9nkzbAsms http://www.youtube.c...h?v=BYllaxuzMk0 http://www.youtube.c...h?v=BYllaxuzMk0 A nicer option if you're going with the simple, upright style of grinder is the Coote. The cost of a Grizzly will get you a good way to a Coote,http://www.cootebeltgrinder.com/, except that once you have the Coote you still need a motor. Used motors are usually scroungable at a decent price, occasionally even free if you're really good. High quality commercial grinders are very expensive, and not within the budget of the majority of hobbyists. There is a great deal of DIY activity when it comes to belt grinders, ranging from Tracy Mickley's No-Weld Grinder, to a kit made by Polar Bear Forge, to all kinds of individually designed on-offs. The Internet is chock full of plans, many of them free. A good grinder can definitely be made at home, even if you lack welding skills, but you'll still spend a substantial amount of money on it. If nothing else, you'll just about have to buy the wheels (unless you have a decent lathe and know how to use it).

Aluminum oxide does occur naturally in some iron ores. And the x-ray gun apparently doesn't distinguish between oxides, and metals in their pure form.

Lee Sauder says it looks like slag to him. I didn't ask him about the chemical analysis, though.

Funny thing, Thomas. The mental picture I had formed was . . . well, actually, it was Gimli. So I was very close!

Depends what kind of ceramic tile, but probably not. The common ceramic tiles for household use are not engineered to handle the thermal shock encountered in a forge, even if they'll handle the temperatures (which they may not). For the temps a gas forge should be able to generate, you want high alumina refractory ceramics. The usual solution to the problem you're describing is a skim coat (or a bit more) of castable refractory or refractory mortar. Tell us where you are (fill out the location block in your profile) and we may be able to help you find some locally. Otherwise there are many online suppliers, which I'm sure are listed somewhere around here. High Temp Refractory on eBay is one option. High Temp Tools (not related) is another.

It also depends what size holes you want to drill.

Ah, I see Thomas already rejected the slag idea. Hmm. Well, regardless, it's mostly iron and oxygen, and that's all I really need to hear. :)

I thought some of those bigger pieces looked kind of slaggy and molten. The iron content seems high for this, but I wonder if you have a slag heap there. At any rate, 65-70% iron is enough for what I'd like to do. The goal would be something like this: http://iron.wlu.edu/Bloomery_Iron.htm Not melting it, exactly. Just stripping away the oxygen to turn it into metallic iron. If the stuff you sold a couple weeks ago came back 97% iron, I wonder if it was wrought iron. Modern mild steels would be around 99% Fe. Was it really rusty? I'll shoot you a PM about getting some of this to try smelting with. The fines are magnetic as well? I could build a riddle to screen out the bigger stuff.

Yeah, crushing it is the hard part. I haven't quite figured that out yet. I have a five gallon bucket's worth that I collected at the site of a very old ore pit out in West-by-God Virginia, but it's in big chunks. It breaks up reasonably easily after pre-roasting, but shrapnel flies everywhere and I haven't yet devised a way to avoid losing a bunch of it. (Not that it should be terribly hard.) I have communicated with Lee a little, but he's a good distance from me. By the way, when you say, "finely," how fine are we talking? I've never had a very good handle on exactly how small it needs to be.

I'm ~90 minutes north of you. I wouldn't pay a lot for this stuff, but I'd sure like to get some. Iron making is in my future, and I have had limited success finding decent quality local ore sources, at least ones that are accessible to me. (I have learned some cool history in the process of searching for the stuff, though.) Shoot me a PM if you'd be willing to part with some. I'm afraid I can't take thousands of tons, though. I'm thinking more along the lines of hundreds of pounds.

Out of curiosity, Larry, what's wrong with the vise? Not that I plan to buy one, but I had read good things about them.

All kinds. You can get good smithing coal from either of those states. But not all coal from those states is good smithing coal.

How big a piece do you need? http://www.speedymetals.com/c-8231-hot-rolled.aspx

Good point.

Drills of this general design go for much less than $375 on eBay, although they can still be a little pricey. It's the drill/vise combo that drove up the price on that set. I may regret this, but I'll mention that there are many varieties, not all were made by Cole, and it doesn't hurt to get a little creative with your searches. A lot of folks selling these sorts of things don't really know what they have. That's all I'm gonna say. :P

As Phil said, they all are. There are easily hundreds of steel alloys, if not thousands, and dozens to hundreds of them are suitable for making knives. Learning to make sense of bladesmithing discussions is going to require that you get fluent with the lingo, which includes the designations for various steels. Here are a few links to get you started. http://swordforum.com/metallurgy/ites.html http://en.wikipedia.org/wiki/Tool_steel http://en.wikipedia.org/wiki/Carbon_steel http://en.wikipedia.org/wiki/Alloy_steel If you want to keep it simple, go buy a bar of 1084 (that's a fairly simple carbon steel containing about 0.84% carbon by weight) from Aldo Bruno, http://njsteelbaron.com/, or another vendor of your choice.

I'm pretty interested in ribbbon burners, too, but according to folks here who've built and/or used them, they don't tune down well. So that's not really what you want for HTing, if that's still your plan.

Larry, as a father of five myself I can barely imagine how you must feel right now. May God give peace to you, your family, and most of all your departed son.

OK, a few other thoughts. First, drum forges are mainly for heat treating swords. I think the design is scalable to a certain extent for smaller blades; if you're planning on doing 10" Bowies or kitchen knives you wouldn't need a 55 gallon drum. You might be able to apply the same principle to a smaller burner in a 5 gallon steel bucket lined with an inch of ceramic wool. As for the thicker refractory stabilizing the temps, I guess that's true, although something the size of a blade doesn't really suck out all that much heat. But it'd also make the temps slower to adjust. (It occurs to me that with a really massive forge you might actually be able to run it up to temp, cut the burner off, and use the residual heat in the forge to HT with. But I've never tried it, or had a forge that massive to experiment with!) I'm not quite sure I follow what you mean about hitting your temps with 1084. Yes, it's fairly easy to HT well, but hot spots will still cause problems. 1084 will benefit from a short soak at austenitizing temps (1-2 min. at the temps you're talking about). If you really want a near-zero soak you'll want to go a bit hotter, more like 1525. 1084 will still make a good blade with what you're planning. Frankly, there's always a certain amount of soak time built into the process, because you're bound to spend a little time eyeballing the blade and deciding whether it is fully up to critical. Roman Landes (German metallurgist) has a post about soak times for 1084 over on hypefreeblades.com. Roman is one of a few people I pay very careful attention to when it comes to the metallurgy of heat treating. If you really want the best of both worlds I think your option B is it. Forges aren't ideal for heat treating, and heat treating furnaces aren't ideal for forging. If you leave heat treating out of the equation it becomes much simpler to design a good propane forge. A thermocouple on the forge seems like overkill to me, but it won't hurt anything. It is possible to build your own electric heat treating furnace, BTW, and it should be quite a bit cheaper than the commercial HIT furnaces I've seen, which are all quite expensive by my standards. Plus, DIY would let you choose the dimensions to suit what you want to do. All the commercial furnaces I've seen seem more or less oversized for blades, even most of the Paragon ones designated as being for knifemakers. (Although having a little extra capacity for HTing tooling and the like isn't necessarily a bad thing.)

Let me just say that I do my heat treating in a solid fuel forge because I also don't have the room for a drum forge, and I have not been satisfied with the propane forges that I've tried for blades. Even using a pipe muffle in a propane forge, I have never been able to achieve the sort of gentle, even heat that I want for heat treating. But I have not tried one exactly like what you're planning, so perhaps I shouldn't have been so forceful in saying it won't give the results you want. I don't think it will, but that's just speculation on my part. Not entirely uninformed speculation, but speculation nevertheless. WIth that said . . . Even with the burner coming in on a tangent to create a swirl, you're going to have direct flame impingement on the interior that's going to create a hot spot. So while the rest of the forge is heating by conduction/convection, you'll have an area there that will be putting off a lot of radiant heat, and the closer you get to that spot the hotter it'll be. The hot spot may be bigger than with a burner that's oriented toward the center axis of the forge, and you won't get direct flame impingement on the blade, both of which are good things. But it'll still be a hot spot, and I think it'll still cause you problems. However, as I said, that's just informed speculation. I could be wrong. I have given some thought to how to reproduce the effect of a drum forge in a smaller package, but all my ideas are untested theory so I'm a little reluctant to throw them out. I will offer one suggestion that you might try if your design doesn't work out as hoped. I have tried a muffle in a propane forge with poor success -- the muffle just developed a hot spot where the hot spot in the forge was -- but the muffle was fairly thin. A thicker muffle might do better, especially with your design. I have considered a ceramic muffle of some sort, but the prices of mullite and similar tubes are pretty intimidating just for experimentation. You might be able to do it with castable refractory. The drum forges usually don't have any castable in them. Just some ridigizer to lock own the fiber particles. (I suspect the rigidizer is just sodium silicate or something similar.) I'll try to get to your other questions later.

On further reflection, forget my last question. Regardless of how you're planning to set and hold the temps for heat treating, that forge isn't going to do it for you. I'm sorry to say it, because I know you've done a lot of hard work on this thing so far, but it's just not the thing for what you want to do. It'll be good for forging big stuff -- it'll work for forging blades as well, although it's excessively long for that. But the burner coming in the side like that is always going to create a hot spot, and because of that the temperature inside is going to vary a fair bit from one spot to another. The temperature your thermocouple reads will depend on where it's placed in the forge. For long, thin stuff like blades, you'll have serious problems obtaining even temps across the whole blade. It's the nature of the design. For heat treating, especially blades, you want as even a temperature as posslble throughout the entire interior of the furnace, and you want that temperature to be very close to the temperature you're trying to achieve in the steel. What you want is something like this: http://www.dfoggkniv...S/DrumForge.htm See how the burner comes in from the end and points down the long axis of the forge? No direct flame impingement on the side, or the blade itself, and the large interior volume lets the temperature even out. No hot spots.

Good work. 2" of castable is way too much, IMO. It'll take a very long time to get up to temp, and waste a lot of fuel, assuming you aren't planning to run this thing 16 hours a day. 1" is more than enough, and less would do fine. Are you planning to try to set your temps by adjusting the burner by hand?