So I think it was in Weygers' book. I saw a system once for permitting the thick green smoke to burn off while the fire coked up. I believe it recirculated the smoke through the blower. Anyone had any experience with their own homebrew systems for this? 

Just theoretical for now. I don't have a forge built at all, so we're not trying to make something work with what I already have. Throw your ideas at me!

I remember seeing something in there, but really, it only smokes much when you first start up, and something else to consider, green smoke is flammable and has been known to blow up inside of blowers, bellows, etc and tear them up.

No or very very little smoke when you light a fire off with the coke. What would you do with the coke from the previous fire? Throw it out?

You have a forge fire for x number of hours, ain't 'cha supposed to be making the coke then?

 

If the fire produces flammable green smoke, only when the coal is first lit up, You can try to ignite the smoke with something like a gas fire starter or a propane torch or similar fire source. Keep the cylinder in hand at all times when doing so. Watch your face & hands when doing so ecause the ignited gas may whoosh up. Also do not hold the torch horizontally. it has a tendency to flare up. Bottled flammable gas should be kept well away from the forge fire. (e.g. acetylene bottles).

SLAG.

Edited May 11, 201610 yr by SLAG
Added caveat

Just trying to spark discussion, but I suppose ye olde "What we do now works, and it's not such a big deal anyway" is as valid a response as any. I just hadn't seen Weygers' illustration anywhere else and I wondered if anyone had done any experimenting with the idea of combustible waste gases from the coal fire.

There's some interesting stuff out there regarding how to burn coal more efficiently to produce steam, and thus, electricity. Not really applicable to blacksmithing but interesting nonetheless. 

I'm a process guy, what can I say? Some of us just want to get to the beating of the metal the fastest way possible; I like knowing how things work, and what people are experimenting with. It's almost as much fun for me as the shaping and forming part.

Edit: Not intentionally snarky. I'm saying that pointing out the "this isn't that big of a deal" is -as- valid, if not moreso, than attempting to overthink the problem

Why over complicate simple?

We use bituminous coal and on start up it puts out a smoke screen that would make the Navy proud.  The way to reduce the smoke is to poke a hole in the top of the coal to let the smoke and some fire escape, much like a volcano. The fire ignites and burns the smoke, creating more draft in the chimney and drawing in more air to dilute any smoke that is not burned. Same idea and procedure with a forge that is open with no chimney.

Ah, I like process guys, Mikey is a process guy. We get a lot of folk jumping in with a fabulous new discovery they've just made, some the fantasies of creative young teens. Most by folk who haven't read much, just jumped in. If some of us old Curmudgeons mistook your meaning . . . Oh well. 

There have been a number of smoke control ideas I've seen in blacksmithing books. Weygers was a world traveler who didn't want to pack all his carving tools with so he put together a shop where ever he landed. His book is my hands down favorite boot strapping yourself into a blacksmith book ever.

There are a number that duct smoke back around through the blower to feed back into the fire and burn completely. I've never tried this but the first time I saw the illustration and claims for "superior" smoke reduction, control, or whatever, I had to wonder, A fire needs oxy to burn cleanly how was feeding it smoke going to do anything but make it worse?

What seems to be the most effective method I've seen is the way you build and manage the fire. Kindle the fire how you wish, I use a rolled up strip of cardboard but lots of guys have lots of methods. (that's the origin of a blacksmith saying) I like to cover the kindling with relatively coarse coal the air and flame can blow through relatively easily. I pack around it with wetted fines, up and over the top  leaving a crater in the center. I poke a hole in the center of the crater till the kindling is exposed and the open hot flame ignites the smoke.

From there on I control smoke by how much air and how tight I keep the mound. The active fire is contained in the voids between coal pieces by the fines sealing the exterior. The only easy exhaust vent is through the crater so that's where the unburned volatiles (smoke) escapes where it meats fresh air and finishes burning.

Of course I'm primarily  gas forge guy but that's how I burn coal and minimize smoke.

Frosty The Lucky.

Weygers's smoke catcher was just for catching and reburning the initial smokescreen, not for use during forging.

"The modern improvement of a hinging smoke-catcher is an additional desirable feature for a forge. It is similar to the antipollutant device in some automobiles. In cars it catches oil smoke and leads it into the combustion chambers of the engine. In the forge, the smoke emission, mixed with surrounding oxygen when starting up the fire, is led by the catcher back into the fire by way of the air intake. Once the fire flames up, it consumes the smoke by itself and the smoke catcher, no longer needed, is hinged out of the way. A relatively smokeless fire is maintained thereafter."

"The Complete Modern Blacksmith", page 101