welding fume extractor

[Maker]

Anyone ever built one? Mum thinks I need some kind of extractor/good ventilation whilst welding in the garage. I'd really rather not leave the door open because it's freezing outside and the prying eyes of the neighbours will look in and probably report me for running a business or something (and get arc eye with any luck).
I was thinking of building an extractor arm thing like a Plymovent or Avani. The arm itself looks fairly simple, just some really light tube with hinged jointy things and flexy tube at the bends but the fan is where I'm stuck, I don't really know anything about it and I've got a few questions. What type of fan do they use, is it something that could be built at home without fancy balancing machines, what kind of flow rate and pressure do they need and how big should the motor be? - just to name a few.
I am really only entertaining the idea at this stage and IMHO I don't really need one, especially with tig welding but it sounds like a fun and interesting project that I'd like to tackle. If this does get to the making stage it will be sometime next summer maybe, I need to turn the garage into a workshop first.

 

[Monkey Harris]

get a henry hoover outside with a long pipe/or 2 joined, near to your welding ,
ive done it works a treat,

 

[J.B. Welding]

A snail shell blower is what to look out for, you need a good bit of suction as otherwise the fumes just waft past the inlet nozzle. I made my own arm and it has a 1/2 horse motor blower on it but still lacks power for some things. If your tigging stainless be careful just now as the chromium etc. is nasty stuff.

 

[chevy2]

I have wall mounted extractor fan about 350mm diameter that generally keeps the air clean in the whole place but still often use a welding fume mask on some stuff.

 

[captain-destructo]

what about an inline bathroom extractor?

 

[Maker]

A snail shell blower is what to look out for, you need a good bit of suction as otherwise the fumes just waft past the inlet nozzle. I made my own arm and it has a 1/2 horse motor blower on it but still lacks power for some things. If your tigging stainless be careful just now as the chromium etc. is nasty stuff.

What did you make your arm from? I've been looking on the Avani website and seen their arms are made of steel or plastic. They also sell blowers by them selves so I was able to see the motor power and CFM.
I'm well aware of the dangers of the highly carcinogenic Hexavalent chromium.

what about an inline bathroom extractor?

There's no way they have enough power to be of any noticeable use, there's someone on another forum who did it with one for an inlet and one for an exhaust and dryer tubing but it looked naff. Half the reason I want to build this is because I want to build it.

 

[sparkysy]

I have a 4inch high flow rate centrifugal extractor for my fumes and 4inch pipe across the roof with shutters for a flexible to plug into works well enough for short sections but on long runs some does flow past, the snail shell shaped ones are excellent, and the blowers farmers use pedistal fans work well too again centrifugal type.

 

[J.B. Welding]

What did you make your arm from? Just a hinged length of 40x40 box with 12mm round above bracing it to a solid wall bracket. I've been looking on the Avani website and seen their arms are made of steel or plastic. They also sell blowers by them selves so I was able to see the motor power and CFM.
I'm well aware of the dangers of the highly carcinogenic Hexavalent chromium.

There's no way they have enough power to be of any noticeable use, there's someone on another forum who did it with one for an inlet and one for an exhaust and dryer tubing but it looked naff. Half the reason I want to build this is because I want to build it.

 

[Kent]

I am looking at putting a system in myself. Thinking of a "push pull" type kitchen extractor such as used on bigger domestic island hoods and commercial kitchens. Have a few contacts for a s/h one as I used to be in be the industry, anyone any experience of this? I feel the well placed over head lighting might also be a help. Gotta put me a new roof on the shop anyhow along with rendering but only doing that when the weather gets better.
Presently working with the top section of the doors open (big double stable doors) and a basic mask, still its about 50 times better than what we used to get

 

[rtbcomp]

Bathroom extractors aren't really upto it.

Vacuum cleaners and those fitted with commutator-type motors are very noisy.

As said, a snail housing type fitted with an induction motor is the best option. I use a Clarke dust extractor (the first one I had was noisy due to a faulty motor bearing).

 

[500e]

http://www.clarkeinternational.com/...le-ventilator/path/cam-industrial-ventilators
These would make a good start

We have 2 of their axial fans in paint room one sucking out with water filter the other blowing in through cloth filter they move a lot of air.
This is not the way if you require a body work finish as there is a to concentrated flow, but for coating steel with primers it really works
http://www.clarkeinternational.com/...24in-hd-axial-plate-fan/path/axial-plate-fans
In fan

http://www.clarkeinternational.com/...20in-hd-axial-plate-fan/path/axial-plate-fans
Out fan

 

[mr migwire]

in my last garage i used an old heater box out of a mk4 escort and some serated field drain pipe, made a goose neck type stand from 1"box and 1"flat bar, even kept the speed controler for 3 settings, work reasonabley well and cost about £10 for stock and fastenings to make.

 

[rtbcomp]

If you do go for a Clarke dust extractor, toilet pan and rubber clay pipe adaptors make a good way to connect them to plastic soil pipe.

 

[Maker]

If you do go for a Clarke dust extractor, toilet pan and rubber clay pipe adaptors make a good way to connect them to plastic soil pipe.

I hadn't thought about using PVC pipe. I could get this, the question is : What diameter?
I'm thinking I could build/buy a snail blower, mount it up on the wall and have an exhaust going through the wall and then build an arm like the one below by making up few hinge things for the joints with flexible tubes in the joints.


I like the idea of the hanging type because it won't take up any precious floor space, like this:

 

[Rocketman]

Health wise you would be better off using a disposable welding fume mask. I say disposable as the cartridge ones are a bit big to get under the welding mask.

 

[wheresmejumper]

I picked up a vent axia inline fan cheap,8 inch fan,10m of 6 inch ducting for less than €100 new.
made a hood from aluminium.cheap but effective.theres a thread somewhere

 

[rtbcomp]

This is my dust extractor setup

http://www.mig-welding.co.uk/forum/media/albums/blast-room.301/

Ignore the gaffer tape connections - I've done the job properly since!

For fumes you wouldn't need the filter bags on the output.

 

[wheresmejumper]

Hey, theres nothin wrong with gaffer tape!

 

[Maker]

I don't think an inline fan would be suitable because there will more than likely be grinding dust go up it and I doubt the motor would be happy about that getting inside it. It probably wouldn't be a bad idea to use some kind of filter for this reason as well.

 

[mr migwire]

switch it off when your not welding. if you want a dust extractor as opposed to a fume extractor then it could get a bit more spendy...