Yeah, say that 4 times fast. lol Anyway, at Glenn's suggestion I threw together a "super-sucker" for the coal forge in the new shop. Works beautifully! The only issue I have is when I kill the blower, after an hour or two, the smoldering coal makes for a little haze in the shop. Looks like a new environmental engineering project in my future. Currently debating making a "hood" that can be closed up with panels when I'm done forging, but first I'm gonna just try moving some air with fans and see if I can clear up the haze. Remember, I'm 10 feet below ground so there's some issues here with airflow that most people don't have to deal with. Here's some pictures of the box I built, a quick test fire (because I had my doubts) and after the forge was constructed, a real honest run.

J

What is the inside diameter of your flue pipe, and how far does it extend above the highest point of your roof? 

What is the inside diameter of your flue pipe, and how far does it extend above the highest point of your roof? 

8" flue.. goes up another 5.5' until it goes through the outter limestone wall (almost 3') then it goes up about 16' or around 5' above the roof. Like I said, only real issue is the residual smoke from the smoldering embers when it's killed and I think that's because there isn't enough heat in the pipe to really create the convection needed to suck it all out.

J

Hopefully those more expert will chime in, but you might wish to try a larger diameter flue pipe.

Hopefully those more expert will chime in, but you might wish to try a larger diameter flue pipe.

If I could make a bigger hole through the limestone foundation I would have, but I'm constrained to a 10 inch terracotta vent pipe already in the wall. Like I said, while running at full heat it's great - pulls flames and smoke 90 degrees right out the box, it's when the heat dies down after an hour or so and the coals are still smoldering that the little plumes of coal smoke linger instead of getting sucked out. I have even considered putting a small propane pilot inside the box just to keep the heat creating a draw.

J

I saw a guy on youtube called Chandler Dickinson who just the other day uploaded a video where he had welded up a box that fit over his firepot and tight up against the opening for his chimney. 

His idea was to stop sparks straying onto the very old and very dry timbers of his shop. - But in theory you could make something similar that would effectively force any smoke up the chimney once you're done for the day. 

 

Just an idea. 

Andy

I threw together a "super-sucker" for the coal forge in the new shop. Works beautifully! The only issue I have is when I kill the blower, after an hour or two, the smoldering coal makes for a little haze in the shop. Looks like a new environmental engineering project in my future. Currently debating making a "hood" that can be closed up with panels when I'm done forging, but first I'm gonna just try moving some air with fans and see if I can clear up the haze.

Lack of heat to power the draft in the chimney would be suspected but the fire is not out and continues to smoldering.

Drag the fire out of the fire pot and it should die rather quickly. You may wish to put a fan in the chimney to encourage the last remaining smoke to go up and out.

Edited August 20, 201510 yr by Glenn

we used to rake the fire into the bottom of the chimney to both put it out and to have the last of the smoke exit through it.

Try a KISS solution just to see if it resolves---make a quickie tin-foil deflector cover to direct residual smoke to the chimney...maybe with a small air-channel so what little draw there is has some make-up air.  If it works, you can fab us a decent cover to throw on when the hammerin's done.

Must be reading my mind because I just picked up a roll of heavy duty foil to do just that at the end of the day.

J

Put some bricks in the bottom of the chimney.  They heat up while you work and will continue to add a little draft while the fire is idling.  I have a side draft with 12" pipe and four fire bricks sitting on the bottom of the box - it's a rare occasion to see any trace of smoke in my shop.

Did the quick and easy tin foil method, I'll try the firebrick idea when I set up for tomorrow's work. 

J

With tin foil tent you STILL HAVE FIRE in the forge !! You are in effect "banking" the fire so it lasts longer. Rake the coals out of the fire pot to kill the fire.

No fire = no smoke and no problem.

 

It's a sideblast, there really isnt technically a "fire pot".. but I do rake the coal/coak away from the embers to the other side when I'm done..

Just make a sheet steel cover to smother it or shovel it into a bucket of water. The coke/breeze and coal will dry out quickly once you strain it out of the water.

Frosty The Lucky.

If you would put in a "switch" in the air duct from your fan so the air goes in trough a kind of jet at the bottom of the pipe directed upwards you will get an ejector effeect that keeps the chimney going. When you close for the day you just redirect the air and rake out the embers so they loose heat quicker. When the embers have stopped smoking, you stop the fan. You use this device also when starting the fire in order to start the draft. Since I do not know your fan I cannot guarantee that it works but a similar setup works very well for me

Göte 

Edited August 27, 201510 yr by gote

JWS I also am limited to an eight inch stack, and I was curious about more of the dimensions on your side draft hood?  Did you just scale down the dimensions given on the anvil fire blue prints for the super sucker side draft?