Thursday, October 23, 2014
I looked at a few forge ideas on the web. They all seemed to have a deep fire pot filled with coke. I thought it might be worth scribbling my idea for the forge down here. I didn't see the point in having all that coke burning when the only bit used was up top and I didn't like the idea of burning so much to heat so little.
I had an old circle of 6mm plate, so I drilled that to act as the tuyer, if one can call it that. I welded that plate onto a short length of 120mm diameter pipe cut to a slight angle pointing toward the blower end, then sat the weird kind of top hat shape in the pot over the air pipe and packed the space around the thing with ash. I cut some scraps of fire brick to leave a nice little tapered pit space for coke to burn well insulated and bring the tops level with the barbecue tray.
Fire bricks can then be arranged as needed on the tray (as in the hammer picture) to make different shaped fire areas depending on the work and hold the stack of coke waiting to burn in place where needed. I thought I was going to need a blast of air and was worried my little blower wouldn't cut it, but really the problem is keeping the air flow low enough not to be cooking coke for no reason.
Although smiths are commonly seen working on the tip of a bar, one also needs to work on sections mid bar and on odd shaped pieces too, so flexibility is good and having the fire high up with space around it allows that to happen without having a massive mountain of coke to play around in.
One idea I would incorporate if building again would be a water trough at the front edge with a dipper or wiper squirter pump to cool bar or tongs when they get too hot to be held as well as for quenching work where needed. Between the fire and that I might have a section cut out and covered with course mesh to allow ash to drop down when sweeping out the fire pit, but not course enough to let coke lumps fall through. You can see a selection of buckets under the forge in other photos set to catch ash. Most of the ash can get down the air holes and down through the cinder flap, but a bigger drop zone would be good to have. The cinder flap is just a circle of steel welded to a small bolt head, with the bolt on and the flap in position the nut is welded to the down pipe so the flap can swing out sideways when one is cleaning out.
One advantage of the scaffolding is that the clamps don't have to be tight so the whole thing can be swung out of the way, or into different positions within a given area. I imagine one day I will set up the forge, etc near to the press and make some kind of more permanent arrangement with a hood etc, but this works for now.
I don't have a hood set up yet, but the ceiling is fireproof and there is a big fan set up next to the forge to blow smoke and fumes out the door, so not entirely stupid.