Following the puzzlement on how I made the loop on my throwing knife instructable, I thought i'd make one on the things that can be done with hot steel. I've missed a few out because i think the basics are covered here. If you want to make a bar thinner, for example, you only need to use a slight variant on Drawing out the bar. If you try this a bit, you'll get the hang of it.
The only thing you have to know is that you're changing the profile of the bar, but leaving the volume the same. You can beat it out into foil, or forge it into a sphere, but it'll still be the same volume.
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Step 1: Upsetting Steel Bars
Not upsetting as in "Making Steel bars Unhappy", but reducing the length of the bar and making its cross-section larger.
Heat the end of the bar, or the bit you want to be wider to forging heat. Place the bar end-down on the anvil and hit the top, like hammering in a nail. If it cools down too much, put it back in the fire until it gets hot again, then carry on. Upset the bar until it's at the desired thickness.
You can use Upsetting to put bulges into a bar, or to make rivets, nails, bolts, ETC
Step 2: Twisting Steel Bars
You can twist steel by heating up the area you want to twist in, grabbing the steel on either side of that area with pliers and twisting it, it's as easy as that. Again, if it gets too cool, put it back in the fire.
Step 3: Hot Cutting Steel Bars
You'll need a hot cuter for this. Mine is an axe clamped in a vise.
(the axe was on fire, not long ago)
To cut a bar, bring it to the correct heat, set it on the hot cutter and hit the steel over the hot cutter. Each hit from the hammer pushes the steel down and cuts it a little more. Only cut partway through the steel. If oyu cut all the way through, you'll probably damage your hot cutter and there's a good chance that you'll have a piece of hot steel flying off into some obscure corner and causing trouble. When the steel's almost done, the hot cutter will draw heat out of it quite quickly, so you'll see a darker line on the bar. Grab the steel in pliers and pull it apart.
Step 4: Drawing Out Steel
Heat the end of the bar, or the part of the bar you want to draw out to forging heat. Hit it on one side, then turn it through 90 degrees and hit it on the other side, then turn it again and hit it some more. Keep turning and hitting it until it gets to the desired length. This is the polar opposite of upsetting a bar.
As always, don't let it get too cold.
Step 5: Bending and Straightening Steel
Fairly obvious how to do this, but i've included it anyway because it was easy.
To straighten steel, heat up the bend, put it on the anvil and hit it with the hammer until it's straight. Chances are, you'll put some smaler bends in as well, sort them out too. It's really as easy as that.
To bend steel, heat the bit you want to bend, put it over the anvil and hit it till it's bent. Again, really, really simple.
Step 6: Making Loops
I know i didn't do a good job of telling you how to make the loop on the throwing knife instructable, so here's a more complete one.
Get your steel and put a 90 degree bend in it. You'll need to put the bend about 3 or 4 inches in, or more or less, depending on how big you want the loop to be.
Put another 90 degree bend in the steel, facing the other way, so you get a step-like shape. The step-bit needs to be about an inch long.
Bend it again about .75 of an inch up from the step, this starts the loop. By now, you should have a question mark shape.
Heat up the back of the question mark shape and bring the end of the bar around, so it touches.
If needbe, or if you want to, bend it over, or straighten it.
There's more stuff you can do with hot steel, but basically, it's all variants on what you've seen here. Flattening, for example, isn't dissimilar to drawing out.
Thanks for reading.