The death of a forge, the start of a new era!

[Gundog48]

I built a 55 Forge a few months ago after I became really interested in the art. I was really excited when I first saw something that I made heat a piece of steel up to that glorious red and then watching the scale fall of as I hammered or bent it. My parents were took a bit of convincing (I'm 16), but my Dad was quite happy that I wanted to do something like this as most of my interests lie with computers and electronics. To me, it's the same thing but a different medium, I just love making things!

After making myself some tongs, a punch and a chisel, I forged my first knife from a 1/2" square ring gear. It was kinda jumping in at the deep end as the ring gear took a lot of work to get the the flat state that I needed, but it was the only high carbon steel I had at the time. Anyway, everything went well and I was rather proud of my first knife. I've been making more, but I'm waiting on a belt grinder to finish them off as the bench grinder I used on the first knife was hard to use for what I needed.

Anyway, I recently switched to coke and found that my blower wasn't up to the job. I was using one of these: http://www.spalautomotive.com/eng/products/view_centrifugal.aspx?id=006-B39-22, a bus demister fan that operates at 24V. I built an adapter box so it would pump the air through a nozzle to which I fixed a hose to the forge itself. I was powering it on 12V from a PC power supply I put in a box with the blower, along with a switch to turn the PSU on or off. I was looking at 24V transformers to get the most from the blower when I remembered we have a variable load car battery charger that basically supplies however much current is needed at either 12V or 24V. So I hooked it up and it was crazy! On full blast it pumps 700CFM, and the way the adapter works, the pressure is huge. I toned it down and got forging, my coke was now getting hotter and I was actually getting flames, whereas last time I had to give up because it just wasn't getting hot enough.

The heat was incredible, I could see the paint burning on the bottom of the 55 Forge which I never got before, and I could see it starting to sag. At this point I knew that this forge was no longer capable of supporting the heat that I needed, so I knew it would fail soon. About 20 minutes in, the air pipe drops off, the aluminium piping had melted through and dropped out. It was a bit of a safety mechanism as it cut the air off, because if the bottom of the forge went, it would be pretty dangerous. When I raked over the coals the heat was like nothing I've felt before, more the sort of heat I would expect a proper forge to have. Anyway, after it cooled and I reclaimed the angle iron legs, this is what was left. Note that the forge has the standard bottom of the barrel reinforced with 2x2mm steel plate with a further 2mm steel plate for the nozzle.







So, what now? I've started work on a more manly forge now! It will be able to cope with the blower at full blast which will be ideal for some light foundry work as well. Obviously I'll normally be running at around 400CFM, but this forge should be able to cope with just about anything. I've fabricated a proper frame complete with casters for moving it around with a tool holder and a holder for the blower housing. It's made from a bus brake drum with holes cut in the side for access. I'm bolting down some really thick steel plate, not sure what I'm going to use yet, but I have access to anything between 1/4" to 2"! I've welded up a nice stainless piping system for the air and possibly a ceramic nozzle. I'm then lining the whole thing with 1-2" of proper refractory clay to make the thing virtually bulletproof. I'll post some pictures of the new forge soon. Needless to say that I am incredibly excited to use this new forge as smithing has become my favourite hobby by far. And now I've done my GCSEs at school, I'm on holiday till September so I want to clock in some serious shop hours!

[pkrankow]

Clay it, get back to work. Drill for a 3/8 rod in the pipe as your grate.

3 parts sand
1 part portland (active ingredient in cement)
optional 1/2 part clay

Use just enough water to make it pack into a ball, and break when you pinch (instead of squishing, too wet)

I guess you'll need an iron pipe instead of the aluminum.

Phil

[Gundog48]

Thanks Phil! I did consider this, but to be honest I want something a little more professional now, the new forge is looking good, bulkier with a proper stand and holders etc. The only problem is that it is flat bottomed, so I plan to make a firepot with the clay, only 2" or so deep as I can stack the coke like I normally do on the old one. I'll post some pictures later today so you can see where I am!

[Rhettbarnhart]

i would still suggest that you line it with clay i have a forge that is probly 100 plus years old and i line it with plain old clay and you can forge for hours without the pan getting too hot to touch

[Glenn]

The original 55 Forge had the pipe stick up an inch or so above the 1/4 inch bar going across the pipe and acting as a grate. This did two things, one it allowed ALL the air going to the forge to get to the fire with no restrictions. Second it allowed a couple of inches of ash to collect in the bottom of the pan acting as insulation.

The side blast version has a 3/4 or 1 inch pipe horizontal pipe resting on a brick and extending into the forge. This allowed ash to accumulate in the bottom of the pan acting as insulation.

Either way the end of the pipe is a consumable that as it burns, just push a bit more pipe in to replace it. You may need to raise the air inlet higher off the bottom of the forge if you use big fires at high heat. This is just tweeking your system to your needs.

I would suggest to open your air inlet full size, extend the pipe about 2 inches above the base of the forge, allow ash to accumulate and insulate the bottom of the forge (no air should be getting to the bottom anyway) and try not to over engineer simple. I use one 3/8 rod on a 2 to 2-1/2 inch pipe and 2 each 3/8 or 1/2 inch rods on a 3 inch pipe opening. This is a very large air opening and all the air from the blower can reach the fire. You will find you need to use much less air as there is no restrictions. The amount of air now controls the heat of the fire. You can build a large fireball and heap coal or fuel up on top and still the amount of air (not the fuel) is the controlling factor.

Always keep a 5 gallon bucket of clean water at your forge. It is great for putting out small fires and just large enough for the entire foot when a hot one goes into your shoe (grin) Always plan for but try to prevent the unexpected, it is called safety.