garage exhaust fan

I have designated an area to put my workbench on one corner of the garage near the garage door, and will be using this to weld
occasionally, too. Here is the picture of the corner:
http://www.sfu.ca/~rhui/house/garage/DSC00974.JPG
My walls and ceiling have drywall installed so would like some kind of fan I can turn on and off to extract the fumes, probably directly above the workbench I think. I could also use it to clean the air if a car needs to be idling in the garage.
I would like to know what kind of fan to get, here is one I found and the installation should be simple enough as I don't have to mess with the roof.
http://www.tamtech.com/garagefanGV7.htm
Please let me know what you think. I know it's tempting to go have 1200 cfm or something like that but I'm only a hobbyist and it would be overkill. Also I'm looking for something that is reasonly energy effecient.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
jeremy snipped-for-privacy@my-deja.com (jj3000) wrote in

snip > My walls and ceiling have drywall installed so would like some kind of

How much fan you need depends on what type of welding you do, how much fumes you get. If I where to do it, as I will once the basement is fixed, I would have some kind of flexible hose for the fan to get the maximum workarea ventilation from the fan. I would not keep the car running with just the fan for ventilation, keep the door open. Henning
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 4 Feb 2005 13:55:53 -0800, jeremy snipped-for-privacy@my-deja.com (jj3000) wrote:

if this is a garage that is attached to your home , I think the best thing you can do is to install a standard 34-X36 " double pane sliding window , which slides up and down.
then place a $10-$30 dual fan window fan unit in it, walmart target or other s sell it. later you can build a small welding boot or welding hood around it.
advantage of a window over a designated fan you have a link above.
1; you have a window/glass, which will provide needed light 2; should you ever need to sell your house it looks good , and adds to the value, and your garage does not look like a shop. 3 fan can be removed any time and window can be shut = no cold air draft. 4 these fans normally allow change in fan speed (3 speed normally) and air dirrection ( in/out) with a flick of a button. very usefull when you want to extract air from the garage or you want to pump fresh air in from the outside. 5 if the fan goes south, you can simply fit an other one in its place at low cost, if you installed a designate fan you are stuck with the size or hole you cut in the wall.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
acrobat-ants wrote:

Heh, I have a medium duty blower belted to a 1/2 hp motor, ducted via 16" flexible duct (think plastic dryer hose only bigger) to a chunk of 1/2" plywood that's sized to fit just inside the basement windowframe. crank open the window, stick this in the frame, open the window on the windward side of the basement, and fire it up! (intake of blower is ducted to a point near where I weld with the plastic, and I then switch to aluminium semirigid ducting in case it inhales liquid metal.
Hunt around scrapyards for belt-drive blowers, and salvage a motor for it somewhere, weld up a frame and away you go.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
jj3000 wrote:

Looks like a drier booster :-) I think the volume is to small.
How about an attic fan at the end of the shop. These are several feet in diameter and are often thermo and switch controlled. The switch is often just used to enable the thermo. Switches are in series. So one can turn off the noisy (if it were) fan at night but allow it when wanted or needed.
Martin
--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer snipped-for-privacy@pacbell.net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
careful on a few things.
1. large diameter fan blades have more chance of building static charge and then a spark can jump. if you're a serious solvent sprayer then you need a "explosion proof" fan.
2. just calc your garage cubic footage. i dont think you want to match your garage CF per minute, wind tunnel. maybe 1/2 or 1/3 your garage CF for a CFM fan.
3. you have a outlet, now you need an equivalent inlet or else you wont move much air and it will be a "low pressure garage". what i've seen most often is a exit up high in one corner and a inlet down low in the opposite corner.
4. i filter my outlet air before the fan. i had my basement 140CFM unit working for 3 days now and the filter has already turned colors. i sprayed just a couple of items with spray can, and i sprayed some poly from my hvlp. the filter keeps the fan blades clean. without the filter you will get crud on the blades making them heavy and less efficient.
hope this helps some with your project...

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Assume a 20' x 20' garage with a 10' ceiling. That is 4000 cubic feet. It would take over a half hour to change the air in the garage. Would this be sufficient for your needs?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.