Wednesday, July 12, 2006


Not your dancing, dammit, the blade. Had time this morning to do the work on the blade I forged a few days ago, so here it is.

For heavy stock removal or odd shapes I use a regular wheel grinder, but for this one I can do everything on the belt sander.

It's a 6x48" belt with a 9" wheel on the side. Since I flat-grind almost everything, it's worked very well over time. If I've got a big blade or a lot of stock to remove, I'll use a 60-grit belt to take off the worst, then an 80-grit for the rest of the rough grinding. Remember, each finer grit has to get rid of the scratches from the previous, so if you take it too far down with the coarse ones you may have the choice of either leaving a ratty-looking finish or making the piece too thin.

I would strongly recommend having a bucket of water handy; the piece will get hot, and it's a good idea to cool it off before you yell "Ouch!" or something more expressive and the belt or disk shoots the piece off somewhere.

One more thing: use a sharp belt whenever possible. A sharp belt(or disk) runs cooler and cuts faster. Please note that 'cuts faster' holds true for your body parts, too; accidentally stick a knuckle into a moving belt, or- worse sometimes because it'll cut- the edge of the belt, and I promise you it will hurt. And bleed. And look like hell while it's healing.

This is not where I usually set this up, but with the chance of more storms I decided, for the one piece, to just set it here.

I started on the disk, using it to flatten the back and curve the point down a bit, then flatten the edge and curve it properly up to meet the back and form the point. Then clean up the butt shape, and touch up the bottom of the grip.

Then I used the 80-grit belt to clean up the work so far,

leaving a nice, clean profile.

Now I like to flatten the sides of the tang. I hold the piece by the point and use a push stick to put light pressure on. With a big blade you might need a heavier stick and a lot more pressure, but a sharp belt helps a lot and requires less pressure.

Do one side, then flip it over and hit the other and you wind up with something like this

If you're going for a clean finish, no hammer marks left, you'd take it a bit further than this, remembering to keep the thickness in mind so you don't take too much off. Generally you leave a piece a little thicker all around so you can grind off all the marks and have the piece the final size you want. A lot of times I'll not do that; for some pieces people like seeing the forge marks.

In any case, you you grind the bevels. You're holding the piece flat on the angle from the back to the edge, not level with the tang. So you have to keep that angle steady while you work; takes a bit of practice. And yes, use both hands; I had to take these with the camera in one hand. Use a push stick as needed to hold things in place. You can let a piece get pretty hot at this stage, there's no temper to ruin. I've seen people use either welding gloves or locking pliers to hold the tang and a push stick to put heavy pressure on, and the metal gets hot enough to burn the stick. So start on one side, work it a bit,

then cool it off and switch to the other side. It's generally best to keep the back toward the direction the belt comes from.

That gets you here

I wanted to clean up the shape where the tang & blade meet, so in this case I clamped it in the vise and used a file to touch it up.

Here it is now

Clean profile, bevels cut in, tang flat. I left some hammer marks in the bevels because taking them off now would make the blade thinner than I want it to be for hardening; with a small piece like this it's no problem to grind them out after. With a big blade, or if you left it thick enough, it's best to take it to at least a 120-grit finish, 240 is better. That gives nice smooth surface, less grinding after heat-treating and thus less chance of overheating it.

I took a hand-held belt sander and rounded off the corners of the table on this sander in the center, leaving the corners square ahead and behind. Did the same thing to round off the corners of the face of the anvil for about the first 1/3 to 1/2 of the face behind the horn.

It's a good idea to have a grinder set where, when it grabs something out of your hands(don't worry, it will) you won't have to search through the high grass/boxes/etc. to find it.

I think it was Wayne Goddard who wrote about using a long magnet as a holder for long blades he was flat-grinding; not only protects your hand from the heat, makes it less likely the thing will go shooting off the grinder if your other hand slips. Someone told him about it, so the idea continues on.

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