DIY fume extractor.

[rkidd]

Looking for some ideas for a diy fume extractor for working in my shop in the winter all closed up with the heat on here in NE Ohio. Looked on You Tube and got some ideas. I just do smaller projects, and will be mig welding not flux core for little fab projects. I would also be painting these items. I am talking like a foot or 18" stuff. Thinking about getting a 150 or 200 cfm bathroom fan, ducting outside, and then hang a hose down close to the work area. Would appreciate any thoughts or experience on this to make sure I get something that will work. Thanks.

 

[flingwing1969]

What is the volume of your shop?

 

[yomax4]

The very lowest cost DIY extractor I have ever seen was a shop vac with no filter sitting outside with the hose through a sealed hole in a partially opened window. He had hooked the hose to a 3'x3' 6" deep pan over his bench. I laughed at it but it was very functional. Drawback is pumping your heat out of the building with the smoke.

 

[RNeumann]

Shop volume would be key if you are planning to move air in the entire shop.

I’d skip the bath fan as it was never designed for that type of use.

I’d be inclined to put in a little kitchen range hood and use rigid ducting to the outside. Don’t forget you will need makeup air if you want it to work properly.
Most welders have a cheap box fan or ten that they keep around the shop to blow fumes away from them while they work. With the box fan and range hood you would have more than 99.9% of home shops.

 

[Gordon Gould]

This is my vent system. Probably not OSHA compliant but neither is any thing about my little basement shop. I can weld down there and not set off the fire alarm that is down there or get fumes upstairs with the door open to let some heat up from the stove. I just remove the filter from the vac and turn it on and off with a foot switch. I put a pvc shower drain fitting in an old galvanized oil pan to use as the hood. Very hi-tech



gg

 

[flingwing1969]

This is my vent system. Probably not OSHA compliant but neither is any thing about my little basement shop. I can weld down there and not set off the fire alarm that is down there or get fumes upstairs with the door open to let some heat up from the stove. I just remove the filter from the vac and turn it on and off with a foot switch. I put a pvc shower drain fitting in an old galvanized oil pan to use as the hood. Very hi-tech
/QUOTE]

Like that except maybe with a long hose leading from the "blower" side of the shop vac to evacuate fumes to the the outside of the house. Make sure the shop vac is NOT one you use for sawdust collection as you may pick up a spark or two. Build an wire hanger onto the shop vac to get the intake hose up out of the way and attach an magnet onto the business end of the intake hose so you can attach it to your work.

Using this, you can move anywhere in the shop with the extractor and work on, say a car frame, and then back to your welding table.

 

[/pine]

bath fan...AKA "fart fan"

I used to do a lot of fiberglass/polyester fabricating and the only thing I ever found that worked truly well was a large fan and louver mounted in an exterior wall...with an equally open window etc. on an opposite wall...

I suggest searching for something like a paint boot ventilator fan etc...

 

[Gordon Gould]

Right in the center of my "shop" floor I have a drain which is vented to day-light. I use it to provide make-up air for the wood stove and the welding hood exhaust.

gg

 

[rkidd]

Thanks for the replies everyone. flingwing 1969, thanks, I should have stated my shop is 24x32 insulated, drywalled and has heat. I do not plan to do heavy enough work to flood the whole shop with fumes as I know what I am trying to do will not work. Just working in a 6x6 ft area of it and try to evacuate the fumes from that area with a hose hanging down close to the work. So come on from there! The reason I was looking at a bath fan was that I could mount it on the ceiling and leave it there,hard duct it outside, have to fab a new lid on the suction side as I know a tinner, with probably a 4" nipple to hook a flexible hose to get close to my work. Just dont know if 200 cfm is enough. RNeumann, thanks, I do have opposing windows in my shop along with the 2 overhead doors, so I can crack the back window for the makeup air. GG, what you have going on there is exactly what I am looking for, for the amount of times I will be doing this. Thought about a shop vac too, and might have to go that way. I was looking for something I could just leave up, and would be quieter than a shop vac running. I appreciate every ones input! So as I am learning about this, is 200 cfm enough to evacuate my 6x6 ft area I am working in, or is there another type of fan I could use to do it, or would I have to get into a shop vac. Bring it back again! Thanks Ron.

 

[Gordon Gould]

Other than being on the hokey side and requiring some safety vigilance the vac does work well. But the only reason it works so well is that I set up the hood directly behind and very close to the weld. I can watch all the smoke getting sucked into the hood. And you are right, it is a pita to set up and the vac is loud. Works for me though, doing my little stuff, and much better than looking out the window at the cold and snow wishing it was warm enough to enjoy some welding out there.

gg