sounds like it could work...you would have to put your actual shop vac unit out side or in a nother room because it just shoots the air raight back at ya... youll need a long hose..

matt

 

... yeah, that was my plan. "...work with the door closed and the shop-vac outside the window."
You are right about me needing a long hose...

-Mondo

 

I tried it with a wet/dry vac, running a hose from the drain opening out a window. In order to get then inlet funnel to pull the smoke in, it was too close to the work and messed with the shielding gas.

 

The shop-vac motor is noisy, and uses brushes which might not last long when used continuously, but it will work. Some years ago, I found a new fan unit which was designed to be installed in a ceiling to supplement the suction fan, pulling moisture-laden air from laundry rooms and such. It had a 6 or 8" diameter, was quiet, efficient and fairly powerful, but I had nowhere to use it so gave it away. New in Grainger's, it cost a fortune but if you could find such a thing at a remodeling project or a surplus store, it would be ideal. You also could construct your own blower unit using a standard fan motor, once you try the shop-vac system first.
If you were working in a corner so the smoke was somewhat contained, this would work better. If the pickup is above you, removal of lots of air is required to get all the smoke.

An ionization filter mounted above, near the ceiling might be a better way to remove the smoke and particulate matter. It might also break down any carbon monoxide; I don't know for sure. So long as the welding isn't putting out any metal-containing gases which you breath as they drift away, this might do what you need and keep the heat in the garage too.

 

A buddy of mine used a box fan in the window. Made a sheet metal shroud for it, and ran dryer ducting over to where he was. Worked pretty well considering he had all of $15 in the whole thing!

 

Haha that reminds me of my grandma...

she used a box fan in the window, dryer tub attached and run up to ceiling with the other end dangling above her..

she was worried about second hand smoke around the children

 

The shop vac is a low cfm but high static pressure device. If you could find an old belt driven squirril cage furnace blower and put a slow motor with a small pully on it, like an old washing machine or dryer motor on it, you would have a quiet system that would give you lots of flow with the minimum pressure you need. When you mock it up, check the motor amps and if the amp draw is too high, block off some of the flow of the blower and the amp draw will go down.

 

Shop vac is a wonderful tool for many things, but sucking up large amounts of air/fumes is not really one of them.

And as Oldiron2 mentioned they are usually noisy. Really, really noisy. And typically not really made for long/continous usage.

A better 'scrounging' low-end choice would be a decent used kitchen range hood. Rig up ducting to exhaust outside.

Another possible choice would be a smaller dust collector, but DO NOT USE IT NEAR METAL SPARKS! You would be using the dust collector just for its air-flow, and again exhaust to the outside and bypass the dust collection bag.

Like imagineer mentioned, you'll have to put a shop-vac intake so close to the welding zone that you will interfere with the shielding gas.

YMMV.

 

there is always this from HF

 

Great tips, all! This is the kind of info I needed. Thanks!
Good coupons, buhler! :cool2:

-Mondo

 

I'm going to mount a bathroom exhaust fan in the middle of my shop. I'll run the exhaust outside using pvc pipe. I'll rig the fan up with a dryer vent hose which I can move around wherever i need it. It's not loud and the fan will last a long time. And the plus is that it won't pull out all of the heat. And if needed I can always install another one.

 

You can get that accordion-style tubing in large diameter aluminum; I think 6 and 8 inch diameter. It can be hung from the ceiling with light wires, can be routed around things if needed, and is fairly cheap too. It may be easier to use that from the fan out to the exhaust port.

 

this is true. it would be lighter and cheaper.

 

Hi, I had the same problems a couple of years ago. I got a fan from a propane furnace, the ones used for exhaust. I mounted it on a small frame, got myself a piece of flex hose at a mufler shop, hooked it all up and works well. I will post some photo's for you when I get home. I wired it up with some electrical receptacles as well, good source of power for my grinders etc.

Guy

 

I use a 120 VAC 4"muffin fan, mounted on a 1" x 12" plank with a 4" hole in it, that takes a suction on
six feet of 4" black corrigated plastic drain pipe mounted on the plank opposite the fan. The plank is mounted on upright 1" thin-wall square tubing that has four outriggers welded at 90 degrees for a base. The plank slides up and down and is held at the desired location by a thumbscrew. The plastic pipe droops about 4" over six feet, but is self-supporting. I usually weld right outside my garage opening and it keeps fumes out of my face and blows them away from the garage interior. Not suitable for a totally enclosed welding area, but the muffin fan and plastic pipe may be cheaper than some of the other suggestions. However, plastic pipe/duct could be a fire hazard if the fan is powerful enough to draw sparks into its discharge path.

 

I did HVAC for many years. We always took the best squirrel cage blowers/ motors out of used furnaces and made bad to the bone shop ventilators out of them. They can run continuous, and are quiet. Plus, they were free, which was the right price for me!!!

 

One of the best fans I have is a little number that came off a junk pile - it's from an old industrial refrigerator or freezer. The motor is less than the size of a softball, made from cast iron, and has about an 8" blade. Whisper quiet, but it moves air nicely.

 

The portable ventillator got me thinking. I already have a Ryobi 40v cordless blower which I can run at the lowest setting using some rubber band on the variable speed trigger. Now I think I can attach some dryer duct on the grill behind the blower and it might work out well and with minimal noise. I will post some pics once I get to do it.

 

Look/ask around at some appliance repair guys for a restaurant hood that's been scrapped. Shouldn't be hard to find and will handle anything a little welder will throw at it. Good volume, pretty quiet. You could rig it up over the bench and make it pivot in a 10-12 foot or so circle. An old body shop exhaust fan will work too since most places have an isolated booth these daze. Spoiled wimps

View attachment P5101727-1024x1024.jpg

 

Yeah, I’ve tried the shop-vac and can validate all that everyone has said.

It’s loud and doesn’t work too well, with its suction you’d think that it’d be great, but it is only strong at limited range. (which is why people say you have to have it too close).

Some good ideas I’ll have to investigate posted here though! Practicing outside has been sketchy with Florida’s random torrential downpours that happen daily.

 

Not enough volume.

 

This is a great thread, good info. I (finally) joined welding web to make a post about fume extraction. Looking into a similar setup - I have a big open air garage, looking to set up an overhead fume hood to shoot the fumes out the back wall.

 

That’s what I’d use. WallyWorld now gets $16 for them but they move a ton of air and actually last a long time. We use them to ventilate the barn for days at a time.. Right now I have 4 of them Force drying the new stain job on my deck before the monsoon arrives. The one thing that absolutely kills them is falling over while running. Breaks the blades half the time so put some sort of base on it as they flip way too easily. Otherwise they work great and run continuously as long as you want unaffected by dirt and dust.

 

1, you are playing in a cold climate.
You can NOT remove what you don't replace. Walk into a restaurant kitchen and you find either a smoke filled room or a makeup air system to replace the smoke filled air the exhaust sucks out.
Kitchens have sufficient waste heat cold replacement incoming air being cold doesn't matter, actually cold replacement air is a plus.

Your little welder doesn't generate much heat, nothing compared to a grill. How will you heat the replacement air?

2, the easiest place to remove smoke is at the source f the smoke. That method requires less removed air because the smoke is more concentrated. Suck smoke as close to the gun as is possible..

3, Shop Vac is engineered to a fairly certain life point. That life is short. The contaminated air you suck in is used to cool the motor.

4, It won't matter if you have a 4 foot diameter turbine connected to a Hemi V-8 in the back yard, unless you replace the contaminated air the fan sucks out, the room will go negitive pressure and the fan stops moving air..
It's more a matter of replacement air than it is a matter of suck.

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