MattBower

I'm sure the guy who made it had a specific use in mind -- but we will likely never know for sure what that was. :)

Unless that's a universal motor, which probably isn't the case, a dimmer will burn it up pretty fast. A choke plate on the blower intake is easy to make with a screw and a piece of plastic or sheet metal. Even cardboard would probably work. I am only an hour or so from you. I'll keep my eyes open for anvils.

There's a reason carbide teeth are *brazed* onto steel saw blades and lathe tooling. Are you trying to say they were TIG welded, perhaps? Tungsten is at least related to (tungsten) carbide.

What is your max service temp? The problem with homemade ceramics is firing them properly. Bricks aren't expensive, and when you figure in the costs of raw materials, labor, energy for firing, and experimental failures, DIY probably isn't saving you anything in the long run.

Welcome Raymond. Here is a thread from another forum that I think you will really like, if you have not already seen it. http://forums.dfoggknives.com/index.php?showtopic=17953&view=&hl=axe&fromsearch=1

If you can't find it locally as cheap or free scrap, you really have to ask yourself how much trouble and expense it's worth. Steel isn't that hard to come by.

One old method is to mix wood glue with sawdust from the handle wood, and fill the crack with that mixture.

Here's a good one, too. Be sure to click through to the next page as well. http://www.georgesbasement.com/Microstructures/CastIronsHighAlloySteelsSuperalloys/Lesson-1/Specimen03.htm

I tend to use the method at the top of Ed's drawing. Countersinking is optional, really. As an alternative to threading the end of the tang, you can also braze on a piece of threaded rod. There are lots of great hardwoods, but I like to use stuff that's hard and durable. A lot of American woods that are hard and durable tend to look pretty boring, in my view. So I lean toward the tropical stuff. But as North American woods go, mesquite and Osage orange (a.k.a., hedge, bodark, etc.) aren't bad. Some of the figured NA hardwoods are pretty nice. I know a guy in Arizona who uses a lot of desert willow, and that looks pretty nice to me. I don't know how hard it is.

I've heard of that method, tried something very similar once, but I guess you have to be pretty quick with the hammering to keep the little spikes from heating up and flattening out. I had trouble with it. The MIG tacks sound much more convenient. :)

Find out the belt dimensions (length/width), horsepower and RPM of the sander/grinder, and how much labor it'd take to get it. Make/model if you can, but that's not applicable if it's a shop-built machine. If you want to do blades, the grinder will be far more useful than the bandsaw and the drill press -- if it's a decent grinder. If it's some silly little 1x42 (not likely if it's variable speed), forget it. The drill press will come in handy if you have to build equipment; hand drills are not much fun for drilling larger holes in thicker stock.

Kitchen oven. Disposable aluminum roaster tray full of sand to even out the temperature swings. (Preheat it before you add the blade.) Oven thermometer to verify temp. (Candy thermometer stuck in the sand, if you can find one that goes to the temp you want.) You should be able to get to 550ish that way.

Thermal Ceramics (the Kaowool people) make a 3000 degree blanket called Maftec, but I haven't figured out where to buy it. I bet it's spendy.

I used to have one of those funky Evergrip screw spikes. I didn't know what it was. Now I'm not sure where it is. :wacko:

Good point. But the "minimum" claim is repeated here, in Table 1 -- and it turns out there's a new standard for all spikes. They've eliminated the HC/LC distinction. It's about 4/5 of the way through the document. http://www.arema.org/files/library/2007_Conference_Proceedings/Improvements_Track_Fasteners_Cope_With_Heavy_Axle_Loads_2007.pdf

As long as we're talking about the blanket, I think the standard grade is rated to 2300 F, and most folks seem to do fine with that, especially with a thin liner of some kind of castable refractory or refractory mortar. There's a grade that's rated to 2600 F, but it's less common. The guys you buy from should know the temp rating, or should be able to find out for you.

Max makes more sense to me because of the bend tests. But if you're going to call them high carbon, it seems you'd also have to specify a min. to distiguish them from the regular spikes. More googling is in order -- later.

What he said. Coal is several times as dense as charcoal (exactly how much more dense depends on a lot of variables), so you'll have to add charcoal much faster than you do coal. I started out with a charcoal forge and used to have to add some fuel after nearly every heat, even using a hand cranked blower. I probably wasn't very efficient, but the point remains. On a per BTU basis, coal is probably more economical unless you're making your own charcoal from free wood. Even then, your labor is worth something.

You are correct. They are not high carbon in the general sense of "high carbon steel." They are "high carbon" in the world of railroad spikes, as spelled out below. http://notcooperedu.org/~stevansk/Keystone/AREMA/Proceed/1_05p02.pdf Section 2.2 SPECIFICATIONS FOR HIGH-CARBON STEEL TRACK SPIKES1 (1968) 2.2.1 SCOPE (1968) a. These specifications cover high-carbon steel track spikes. b. A supplementary requirement, Article 2.2.14, of an optional nature is provided. It shall apply only when specified by the purchaser. AREMA Manual for Railway Engineering 5-2-5 2.2.2 PROCESS (1968) The steel shall be made by one or more of the following processes: open-hearth, acid-bessemer, electric-furnace, basic-oxygen. 2.2.3 CHEMICAL COMPOSITION (1968) The steel shall conform to the following requirements as to chemical composition: Carbon, min, percent: Acid-bessemer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . 0.20 Other processes (Article 2.2.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.30 Copper, when specified under supplementary requirementArticle 2.2.14, min, percent . . .. . . . . 0.20 2.2.4 LADLE ANALYSIS (1968) a. A determination for carbon and copper, when copper is specified, shall be made of each heat of steel. This analysis shall be made from a test ingot taken during the pouring of the heat. The chemical composition thus determined shall be reported to the purchaser or his representative, and shall conform to the requirements specified in Article 2.2.3. b. When ladle analysis cannot be furnished, the manufacturer shall submit a report of the chemical analysis made on three spikes selected at random from each 10-ton lot. 2.2.5 TENSILE PROPERTIES (1968) The manufacturer may, at his option, substitute tension tests for the chemical analysis specified in Article 2.2.3, in which case the finished spikes shall conform to the following requirements as to tensile properties: Tensile strength, min, psi. . . . . . . . . . . . 70,000 Yield point, min, psi . . . . . . . . . . . . . . . . 0.5 tensile strength Elongation in 2 in., min, percent . . . . . . 25 2.2.6 BENDING PROPERTIES (1968) a. The body of a full-size finished spike shall stand being bent cold through 120 degrees around a pin, the diameter of which is not greater than the thickness of the spike without cracking on the outside of the bent portion. b. The head of a full-size finished spike shall stand being bent backwards to an angle of 55 degrees with the line of the face of the spike, without cracking on the outside of the bent portion. 2.2.7 NUMBER OF TESTS (1968) a. When the option in Article 2.2.5 is exercised, one tension test shall be made from each 10-ton lot or fraction thereof. b. One bend test of each kind specified in Article 2.2.6a and Article 2.2.6b shall be made from each lot of 5 tons or fraction thereof. 5-2-6 AREMA Manual for Railway Engineering 2.2.8 RETESTS (1968) Spikes represented by bend tests failing to meet the requirements prescribed in Article 2.2.6a and Article 2.2.6b may be annealed and resubmitted. If the spikes fail to meet the third test, they shall be rejected. 2.2.9 PERMISSIBLE VARIATIONS IN DIMENSIONS (1968) The finished spikes shall conform to the dimensions specified by the purchaser, subject to the permissible variations specified in Table 2-1. 2.2.10 FINISH (1968) All finished spiked shall be straight, with well formed heads, sharp points and be free from injurious defects and shall be finished in a workmanlike manner. 2.2.11 MARKING (1968) A letter or brand indicating the manufacturer and also the letters “HC”, indicating high carbon, shall be pressed on the head of each spike while it is being formed. When copper is specified, the letters “CU” shall be added.

Extremely impressive work. You should be proud of those. What's your technique for holding the 5160 on the flat face while you heat it for the weld? Or do you heat separately and join them at the anvil? (I always ask this question when I see that sort of weld. )

Most homemade blowers I've seen, including the one I made when I first started smithing, have been crude and not very effective. Yours, however, is pretty slick. Nice work.

For charcoal, call around to your local restaurant supply places.

Bog iron is a raw material -- a form of iron ore. It's not something you pour; it's something you can smelt into iron by exposing it to high temperature in a carbon rich atmosphere, which strips away the oxygen in the ore and leaves behind metallic iron. Depending on the smelting process used, the end product can be liquid iron with high carbon content (which is then poured into "pigs" to solidify, becoming pig iron), or it can be a "bloom" of solid iron (with relatively low carbon content) and slag, which you can then further refine in any number of ways to form various grades of wrought iron, shear steel, crucible steel, etc. Limestone has often been used as a flux in smelting iron ores into pig iron in blast funaces, and in furnaces that convert pig iron into steel. Its purpose in those furnaces is to combine with impurities in the iron and carry them away as slag. Ductile iron is a finished product that you get by adding magnesium, cerium, or various other metals to molten cast iron just before you pour it into a mold. (Pig iron might be the raw material for this process.) This causes a reaction that makes the carbon in the cast iron form into balls (spheres) of graphite. It apparently also causes some pretty impressive fireworks. Ductile iron is not generally a raw material used for producing malleable iron, although I suppose scrap ductile iron could be remelted for that purpose. Malleable iron is a separate finished product that you can get by pouring cast iron into a mold and allowing it to cool fairly quickly, forming white cast iron, then subjecting the finished product to a medium-high heat for a long period of time, which allows the graphite to migrate through the iron and gather together in rough spheres. (Pig iron might be the raw material for this process as well.) It is similar to ductile iron, but not as tough.

In theory, with a severe quench, 0.3% carbon steel could achieve RC 55, which I would consider to be in the lower end of the knife range. Wear resistance would be poor. I would not call it a serious knife by modern standards, but it's not exactly useless. Probably beats most of what passed for knives through a great deal of human history. 0.2% carbon steel can achieve only the upper 40s RC. (That matches up well with Robb Gunter's results of up to RC 48 in 1018 quenched in a lye solution, since 1018 can contain up to 20 points of carbon.) It'd be better than a sharp stick, and a lot tougher than a piece of obsidian . . . My buddy with the spectrometer has run a couple spikes, and they turned out to have 0.25% and 0.3% C. But if you're going to do the work to forge a spike into a knife, for a few bucks you could use a real high carbon steel, do about the same amount of work, and produce a serious blade.

Just remember, what he caught there was recalescence, when the blade was cooling. You want to catch the shift on the way up, which can be very tricky. You need dim ambient light, and it helps a lot to have a forge that isn't much hotter than the temp you're aiming to achieve. A very gentle blast in a good bed of real, glowing charcoal is pretty good.