Routing Welder Exhaust and Welding Fumes Outside

[bbrown4804]

I have a older Lincoln 400-SAE gas powered welder inside our shop along with a 220v Forney buzzbox and for the past 15 or 20 years the exhaust from the Lincoln hasn't been routed outside as well as the fumes from both. The fumes weren't a problem because almost all welding had been done outside or done with the front doors open. But this is impractical during winter, as well as COLD, and it's a pain to drag my 120ft. leads from the welder (which is in the back of the shop) outside just to weld on a small project; so I have decided to move my operation to the back of the shop where it is protected from the elements and from people tripping on my leads. This would put me where all the exhaust is along with the welding fumes from me welding. For winter we have a real heavy duty tarp that seals the front half from the back half where the big Lincoln is.

I have thought about putting in a dryer vent (the kind which has a cover and a flap that closes when not in use) through the metal wall and running the flexible metal hose the three feet to the Lincoln's muffler, but was wondering if it could stand up to the temperature of the exhaust? About the welding fumes, I was thinking about mounting another dryer vent then having a fan like this one 4" Inline Duct Fan on the other side with about 6ft. of the flexible dryer vent hose to put the inlet right next to where I'm welding. The thing is that I don't know if the fan will pull enough cfm of air because according to my welding books you should have a minimum of 200cubic feet per minute of air flow at the inlet with it being 6 to 8in. inches from the arc when welding with 3/16in. and below rods with more air flow being needed for bigger rods, but my though is something is better than nothing. Also the shop isn't insulated, just I-Beams and the roofing steel. Any questions or comments would be appreciated. :newhere:

FYI about 5ft. to the left from the middle/chimney is where the big Lincoln is. The shop is about 25ft. by 75ft. and was built with the Lincoln welder.

 

[Shield Arc]

I don't know how you put up with all the unnecessary noise!:confused2: I have several SA-200s, I built a 12 x 16 pole barn, with 2-foot eaves (steel roof, and one wall) just outside my shop, ran the leads and remote lead under one of the doors. I can still hear the engines if something goes wrong, but they don't drive me crazy listening to them!

Maybe you should look into the flexible steel exhaust tubbing from your local automotive store?
I also have an industrial louvered exhaust fan cut through the wall, just under the trusses over my CNC plasma table, I turn it on whenever I'm welding / cutting.

 

[grsthegreat]

Personally, id build a little shed outside for the welder unit, as i have a great fear of CO gas poisoning. I had a friend die from it.

Also, the noise in a closed shop...yeiks.

I do my welding indoors, i crack open the door and roll up the 12" door about 1 foot, i turn on a louvered 220 volt fan i bought from a greenhouse supply company, AND i wear a respirator unit (Called a hobby air ) that brings in outside air via a 50' hose to a half face mask i can wear under my hood.

I do most of my welding with 7018 rod and reverse dc. Just reading the warnings on the welding rod box should scare anyone.

I certainly don't think a bathroom exhaust fan would work. Consider a standard 30x40x14' shop = 16,680 CF of air available. Moving even 120 cf/min it would take 140 minutes to circulate all the air. My greenhouse exhaust fan moves 4,900 CFM. so even it would take 3.4 minutes to circulate the air. I use the personal respirator as a safety backup unit. A 25x75 by (14' ?) shop = 26,250 CF. yikes. even at 200 CFM = 131 minutes to move all the air volume.