RE: DIY Fume Hood

From: Robert W. Schramm ^lt;[email protected]>
Date: 10/23/05-08:54:44 PM Z
Message-id: <BAY106-F243E3E640EB70324496FDD0770@phx.gbl>


I built my own fume hood about 5 years ago. I started with a large darkroom
exhaust fan designed to exhaust a 12 x 12 ft darkroom. I found a "sample"
storm window about 2 ft x 4 ft with sliding
glass wi ndows which I used for the front. It was screwed to the front and
sealed with silicon sealer.
I built the box out of 1/2 inch marine plywood on a 2 x 4 frame. It sits on
2 x 4 legs. As the plywood panesl were attached (via screws to the frame) I
used pleanty of silicon sealer between the plywood and the frame. The box
received multiple coats of paint. First undercoat and then several coats of
enamel. The box was wired for an AC outlet (outside cover), red light, and
white light and,of course, the blower. I mounted the blower on the back of
the box, caulking it with more silicon sealer and caulking the holes through
which the AC cables ran. The fume hood was bolted to the floor in front of a
window. I made an insert for the window with a hole for 6 inch galvanized
furnace pipe. This pipe was attachwed to the back of the blower and went
through the window and up in the air about 12-15 ft. A rain cap was placed
on top. All of the pipe joints were sealed with tape.
I tested the fume hood by opening the front about 6 inches and placing a
large smoke bomb inside and lighting it. The smoke bomb produced a large
amount of smoke but none escaped the fume hood.
Now I know that the wood and paint are subject to attack by chemical fumes
and spills as is the blower and pipe, but the blower was desigened for a
darkroom. I suppose my homemade fume hood will have a certain lifetime, but
I have been using it for more than five years and I test it evey year. There
is a flow meter you can buy. So far it is still in good shape. BTW
commercial fume
hoods start at around $2500.
The pipe sticking up above the roof looks like the vent for a small wood
stove. My nearest neighbors are about 2000 ft away in all directions. You
could easily insert an activated charcole filter in the vent pipe if you

Bob Schramm
Check out my web page at:

2px solid; MARGIN-RIGHT: 0px'><font
style='FONT-SIZE:11px;FONT-FAMILY:tahoma,sans-serif'><hr color=#A0C6E5
From: <i>Michael Koch-Schulte &lt;;</i><br>Reply-To:
<i></i><br>Subject: <i>DIY Fume
Hood</i><br>Date: <i>Sun, 23 Oct 2005 11:09:17 -0500</i><br>&gt;Does anyone
have plans for a DIY fume hood. I'm going to move my mixing prep<br>&gt;area
above ground to a corner of the garage. Has any on the list built
their<br>&gt;own. What materials work best? How about minimum flow? Piping
d) all of the<br>&gt;above and more. Thanks.<br>&gt;<br></font></BLOCKQUOTE>
Received on Sun Oct 23 20:55:05 2005

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