Coal forge question

[Momatt]

Hello, I’ve been smithing for a few years now as a hobby.  I’ve always used a chili gas forge.  It’s been run hot now for a decade and stored outside. I’d like to switch to a coal forge as I live in the middle of nowhere now on 460 very rural acres. Smoke is no longer any concern and gas is a long way away.  I’d like the ability to heat more specific areas, and not worry about fitting something into the forge.  I successfully forge weld in my forge all the time but it never gets to sparkler heat and I’d like that extra heat level.
 

Ive been watching for an antique to pop up but now leaning to buy one from centaur forge or build one, probably with a fire pot from dave Custer.  How thick should the steel be surrounding the fire pot?  Is a hand crank blower a pain?  I’ve never used one.  Should I buy a new blower or pick up an antique.  Please share your thoughts and insights!

 

matt

[BillyBones]

I built my forge. The steel around the fire pot i used is 3/16". 

A hand crank blower takes a bit to get used to using. I used an old hair dryer till it gave up the ghost. One year around Christmas i jokingly told my daughter i wanted a hand crank that was locally being sold for $400 dollars. She did not get that one but did order one from that online store named after the giant river in S. America. I have been using it since spring and it works dandy. I think it was listed for around $150 or so. Also switching from the hair dryer to hand crank i drastically reduced my coal consumption. 

[anvil]

You can't beat a on line forge firepot setup. I've used them since '79. However, I just purchased a new one from someone who advertised here, but I don't remember his name. Both are ~ 10x14 and 4" or so deep. For me, a twyre and clinkerball are mandatory. 

I prefer cast, but have never used one made a fabbed one. The only difference may be how long they last. 

I recommend blacksmith coal over anthracite. You should have no problem finding it in your part of the world. Check horse shoe supplies or your local ABANA affiliate. Coke works too. Also I recommend buying a ton when you buy coal or coke. Its far less expensive and you only need to make a single trip every year or so. Of course this depends on your own situation.

In my shop I have always used a hand crank, a Champion 400, 14" and swear by it. I've used electric in other shops with no problem as long as there is an air gate to control air. There aren't too many differences. 

My forge was an antique, a 2'x3' rectangle, cast with a flat bottom and no twyre ranch forge. I cut an opening for my first on line forge firepot and it works well. 

The versatility of coking coal/coke over gas is well worth it, as you have mentioned.

[Momatt]

Thanks Billy and anvil!

[anvil]

I reread my post and don't know how this happened: "You can't beat a on line forge firepot setup". Should say You cant beat a Centaur forge firepot setup. Sorry for that.

[ThomasPowers]

The firepot profits from some thickness.  The "table" it sits in doesn't.  So plate for the firepot (or cast iron) and sheetmetal for the table.

[JHCC]

Just as long as the table has enough strength to support the firepot without sagging. That can be done either with a thicker plate or with bracing on the underside.

[Frosty]

My original too large coal forge is 48" x 60" with a 2" x 2" angle iron rim, the table is 14ga with relatively small angle iron bracing across the 48" side. It doesn't have a firepot, it's a "duck's nest" forge. The original fire grate was a piece of 5/16" plate with a series of 3/8" holes in it that laid on the forge table centered over a 3" dia hole in the table. The "tuyere" is 3" x 12" exhaust pipe vertical with a 3" exhaust flap cap clamped to the bottom and a 14ga flange welded to the top end. It's held to the forge table with self tapping sheet metal screws. The air supply is 2" exhaust pipe entering the vertical pipe about 3" from the top, leaving about 7" of the vertical pipe as an ash and clinker catcher. This deep puts the ash far enough below the air blast it doesn't get carried back up into the fire and before it fills enough it might it's heavy enough to self dump through the exhaust flap cap. 

The rendering below is the first take, call it release 1 Do NOT build the flap in the drawing a clamp on exhaust cap works really well without the hassle. It also doesn't show the "bolt" flange on top, I winged that as I built it. 

The air grate I ended up using instead of the hole grate is 1/2" round stock bend like an open hair pin, long enough to overlap the hole over the tuyere. I haven't looked in years but there are enough grate pieces to cover the hole and they're held in place by the clay packed on the table. Later I was gifted a whole bunch of really large fire brick from relining a coal fired powered plant and the table around the air grate is a layer of those. IIRC they're around 3" x 9" x 18". The "duck's" nest is a gap between the boiler bricks, I adjust the fire's size and shape with standard hard firebrick arranged as needed around the grate.

After all that description there are hundreds of lb. of brick and clay on a 14ga. table with two small angle iron braces and it's held just fine for a good 20 years. There is no, as in ZERO need for a plate forge table.

Unfortunately I don't use it, decent coal is just too hard to come by here. You can have it shipped up or go dig it yourself so if I need a solid fuel fire I use charcoal or wood in my Buffalo rivet forge. 

Frosty The Lucky.

[Momatt]

Thanks frosty, sounds like a really neat forge, too bad the coal situation is not great there. I’ve been thinking of cooking a drum of wood inside a 150 gallon oil tank and making batches of charcoal. I am unrestrained by neighbors for the first time in my life and have unlimited wood.  I don’t want to forge with it but I have a  extra large green egg kamado grill that eats a bag of lump every time I use it 

[M3F]

Personally I prefer the hand crank blowers.  I have more control of the heat, I don't need electricity for it, it's pretty effortless to crank and I can quickly get the steel to the anvil without fiddling with on off switches or airgates. I used a cheaper Buffalo forge blower for years till I upgraded to a Champion 400.