Underpowered forge

[IronJeff]

My brake drum forge seems under powered. It struggles getting the steel hot enough. I'm not sure if the problem is not enough air, too small a Firepot, or that I'm using charcoal. Maybe is a combination of those.

It took all afternoon to make a few nails, and it was hard to get 3/8ths square past cherry red. It is outside under a tree so sometimes when the sun is coming through the trees it is hard to tell.

Here are some pictures so you know what I'm working with.

[Iron123]

is there a door sort of thing on the side of your blower ? also did you clean out any clinkers or crap from the pipes? I don't know much about coal forges but just trying to help.

[Charles R. Stevens]

Charcoal likes a deep fire, say 8" all up. Say a 4" bowl and 4" mounded up around it. The fire it's self needent be more than the size if your fist, too the size of both nested together. A hair drier is more than sufficient with a 2" inlet pipe, and a grate.
You may try sticking a coupe of bricks on edge on eithe side to make a deaper fraught to keep it hot, and efficient.

[Charles R. Stevens]

After looking a bit closer at your pictures, I would suggest a few other things that might be casing you problems. The 90 deg. bend out of the blower should be eliminated, the friction reduces air flow, as should the reducer going to the forge, use that large 90 (after a good some in viniger to get the zinc off of it) now you h e minimum restriction, again you may want to eliminate the small floes flange and go with a 2" with a 1/2" bar across it. Charcoal likes high vallume low presser.

[Glenn]

See the ring around the brake drum in photo #3. Cut a piece of sheet metal long enough to match the circumference of the ring plus maybe 2-3 inches. It should be about 9-12 inches wide. Place it in the ring and clamp the overlap together with a C clamp or what ever is available, including drilling a hole and putting a bolt in it, or using screws to hold it together.

 

Now fill the 3-4 inch deep brake drum with charcoal, and add more charcoal until you are well over 1/2 way up the new walls. Look for the fireball and see if it is large enough to heat the size of metal your using. If not, fill it to the top.  Cut a 1 inch slit down the side of the wall so you can insert your metal into the fireball about 2/3 of the way up the fireball.  Too wide a slit and the fuel can spill out, too narrow and you can not get large steel into the fire. Cutting the slot too deep and you get below the sweet spot of the fire.

 

Fuel does not make heat, AIR makes heat. You can over fuel a solid fuel forge. Play with the air until you get the amount of heat you need. You may find it is a smaller amount of air than you thought was needed.

 

 

Reference material

How much air does a forge require.

[ThorsHammer82]

get rid of the 90* bend out of the blower and get larger pipe. 2" is a good size to shoot for but 1.5"-2" works well. Mine is 1.75" and I can burn metal. are you using lump charcoal or briquets? Briquets have a binder in them that makes them not burn as hot as lump charcoal. 

 

you can use fire clay to shape the fire bowl to help with the airflow and to bring the fire up in the drum to make the sweet spot right at the edge of the drum so you don't need to cut the edge of the drum down.

[IronJeff]

Real wood charcoal. Some that I made some from the store. I will work on the airflow, and I think I can make a bigger area for the fuel. I have an old portable firepit to modify.

 

 

More air, lower flow and deeper fire. I will work on both.

[ThomasPowers]

Since the pattern welded viking swords and japanese swords were forged in charcoal fueled forges it's probably not the fuel; but more likely how you are using it.

[yahoo2]

I do a bit of forging at a museum that uses charcoal. they have made an adapter to spread the air as it comes into the pot. imagine a shower rose instead of straight out of the tap. Its pretty simple they made a steel ring about 3 - 3.5" dia and dropped that over the air hole then cut a bit of plate to just sit on top that has a heap of holes drilled in it, only held in place with gravity and crud. No awards for slick engineering and I hate using it but it does give me a bigger hotspot and a gentler blast to work with on charcoal. Not much good if I forget to take it out and switch back to coke, have to crank like blazes to get any heat.