brake rotor forge AND corn as a fuel

[Randy Rue]

apologies for poor punctuation and typing, I'm too lazy to sit at my desk so I'm thumb typing from my phone

my homebuilt gas forge doesn't reach welding temps and can't do a localized heat so I built what I thought was a pretty good brake rotor forge. I also got excited about corn as a fuel as coal is hard to find in the Seattle/Everett area

after two sessions now of forging with it I'm realizing a) why folks stress that a brake forge is mostly good as a cheap entry point and b) why I've only found a little mention of corn along the lines of "sure, it works I guess" but nobody claiming to use it full time

I did find anthracite at Tractor Supply and had a much easier time with it. for example, corn has a big old flame above it. corn doesn't get hot enough with the blower damped but blows loose if I crank up the air

but when planning for corn I built the forge with a simple disc with drilled holes for the tuyere. with coal I can work for about 45 minutes before the clinkers kill the fire

also, with both fuels it's hard to get the right spots on my stock hot, as the fire pot (brake rotor) has a flat bottom with air coming up the center

so I'm thinking of "coning in" the pot with refractory cement, and adding a clinker breaker

I welcome feedback and have a specific question: I'm using 2" square tube below the pot (had it on hand). should I use a cubical block on a shaft for the breaker? if so, how big?

ok another question. I have some Rutland 211 dry mix refractory mortar on hand. was gonna try that mixed 50/50 with sand to fill in the pot. worst case is it fails and I break it out?

[The Jeff]

You can use wood, it will burn down to charcoal.

But go easy on the blower or you will blow the smaller peices of charcoal out of the forge.

[Daswulf]

You could try using lump charcoal and go really easy on the air(you probably have read not to use the formed briquettes). Anthracite coal can work but it is not ideal and takes more air to keep going.  

One thing I notice is that you dont have pass through holes in the fencing of the grill to get the stock lower in the fire. Those will help. 

Also build up the fire if need be. 

On my brake rotor forge the bottom outer edges just build up with ash or fuel so I've never felt the need to fill that in. It never seemed to be an issue. 

I dont have a clinker breaker but use a few different tools to maintain the fire. One is a curved poker to poke down in the holes in the tuyere if it seems to be getting plugged up. Another is a angled end poker to work the fire and pull out any clinker. The other is a larger long handled spoon to add fuel and for general poking around the fire. It is also good for cleaning out the forge pot when needed. 

Fire maintenance is important with a solid fuel forge like this.  Every once in a while youll need to keep some hot coals going and clear out the clinkers then build the fire back up. 

What size holes are in the tuyere? Too small and they get plugged up faster. You just want them small enough to keep the fuel from falling down and out.  That may vary depending on what size the fuel is. 

Also what size is the inside of the rotor? I find that around 8-9" dia. And around 2-3" deep work well.