||[Nov. 27th, 2005|02:30 am]
Finally got everything aligned and assembled for the new forge! Test firing now, got some damascus to make!
Body is a portable air tank, burner is the one from Michael Porter's book "Gas Burners for Forges, Furnaces, and Kilns". It's lined with 2" of kaowool, coated with satanite and IR reflector ITC100. I ended up borrowing the regulator off of the old NC tool forge as the one I bought for the project seems to be malfunctioning (possibly it has some water in it, I'll disassemble it and see if drying it out helps).
First test piece is some wire rope for the xmas project. The rope is "Super Improved Plow Steel" aka 1095 or some close variant thereof. I unraveled a 1' piece of 1.5" dia rope to it's constituent sub-bundles to get the pieces I need. To remove the grease and gunk, I boiled it in a dishwasher detergent/water solution, and when that didn't get rid of the grease, soaked it in solvent, then dried and soaked it in a borax solution to get the flux into all the nooks and crannies.
On firing, I discovered I didn't have much propane left, but was able to weld up the test cable easily. I'm not sure the new forge is as hot as I'd like, but for now it will do.
Since this was just single-twist rope, and only about 3/8' in diameter, I got a rather skinny piece of steel out of it, but rolling it out to 1/8" got me about 18" from the 1' piece. Nice ratio. Next, I tried welding back up a piece of O1/L6 I'd delaminated while playing with the rolling mill. It took a couple of tries, but it seemed to work.
I got another load of propane and cranked the burner up as high as I could get it . . . nope, still not as hot as I'd like. well, I was planning on relining the NC tool forge, looks like I'll be rebuilding the burners as well at the same time. 3 1/2" ejector burners should do the job, and if *that* doesn't work, then I'll build a blown burner that will do the trick.
Some things I've learned while working with the rope: welding up thin section and small diameter stuff is hard -- it doesn't hold the heat very well. Fortunately, the carbon is high enough that it will weld OK at a lower temperature. Getting the ends consolidated and welded up first is a good approach -- otherwise the ends tend to bristle out while you're working on the other bits. The stuff seems to absorb flux, not sure if that's good or bad. It's a good idea to square up the stock before running it through the rolling mill, as otherwise the edges tend to not weld up right. folding it over on itself is a pain. A small forge, possibly one of those single-firebrick forges, may be a good idea for work like this, maybe acetylene powered. it feels silly using a big forge for a knife three inches long and an eighth of an inch thick.
This is still fun, figuring out a new methodology, but we'll have to see how good the pattern looks, not to mention to see if the welding job was good enough to hold together while doing the final forging, grinding, and polishing.