I’m in the beginnings of reconstructing my workshop after our move
to new digs and I thought I would try to recreate ad upgrade my
dust/fume collection system. In the process I’ll pass along my
proverbial 2 cents worth.
First, I would never, never use a shop vac because every one I’ve
ever known has been intolerably noisy. I hate noise. One of the joys
of my metalwork is that, generally speaking, it provides a
relatively quieter work environment compared to the 40 years of
woodworking machinery I’ve worked around. Oh sure, tap tap tap and
scratch scratch but no multi-horsepower, howling, brain-scrambling
In my jewelry/metal shop I divide the dust/fume collection chores
into two categories.
First - the areas which did not require high volume/high speed
extraction - pickling and soldering.
The second category area is to do with grinding/buffing and the like
where the machinery tends to throw stuff in all directions.
For the first category I supplied myself with a few of those little
cooling fans that come from computers. They are light, small and
quiet, run on low voltage DC current and, if you know anyone who
repairs and services computers you can get them for nothing or next
to nothing. Local surplus store here was selling them by the
barrelful for a couple of bucks each. To power them rummage through
that pile of old AC/DC transformers that every 21st century
household accumulates in the back of the “miscellaneous” stash. The
ones left over from your kids’ slot-racing cars (remember them?) or
your old cassette players (remember them?) Find the one that
delivers the output your fan needs - usually 12 volts. Or, sigh, you
can buy one at Radio Shack - Cheap! The wiring to the fans can be
very light stuff, like speaker wire. Run it where you want, fix it
in place with tape or staples, no worries about dangerous shocks or
hiring electricians. Install a simple toggle switch (Radio Shack
again) where it is handy. I found some fans that were just the right
size to be a friction fit inside the flexible plastic ducting
normally used for clothes dryer exhaust. Slipped 'em right inside
the duct, wrapped some tape tightly around the outside to hold 'em
in place, poke a hole in the side of the duct for the little wire
ends to stick out and hook up to the power and we’re away. The
outside end of the duct goes through the wall of the shop with the
same dirt-cheap fittings you’d use to install your clothes dryer.
The “business end” of the duct can be adapted to the task it serves.
For my pickle pot - I had the pickle on a small electric hotplate
which sat inside an enclosure - essentially a simple plywood box on
a bench top. The front of the enclosure was hinged like a door. The
exhaust duct came down to a hole in the top of the box and kept
enough airflow going up and out of the shop so I didn’t accumulate
acid fumes and condensing steam on everything. The sound is almost
For soldering - a similar arangement except the “fumehood” at the
business end was made of a galvanized bucket, upside down, with a
portion of the side of the bucket cut away to allow a big enough
opening so I can manipulate torch, solder etc. I used the cut-away
piece of the side of the bucket to make a sort of baffle near the
hole in what was the bottom of the bucket (now the top) to prevent
flame and streams of very hot gas from going directly up into the
duct without first mixing with the ambient airflow. This might not
be sufficient precaution if working with large flames but was OK for
ordinary small soldering operations. The whole bucket was hung from
above with a small pulley so it could be hauled up and out of the
way - or lowered down onto bench top for soldering operations. Never
had a problem and it was also quiet. Also it was relatively dark
inside the bucket so I could more easily see the color of the metal
as it was heated.
The advantage of these small fans, aside from the quietness,is that
they don’t suck all the heat out of your shop in the wintertime.
IMPORTANT - Make sure you test to see that the fans are blowing the
right direction when you install them - to the outside, not inside.
For larger volume extraction I am going to improve on a system I
used in my last shop. In that one I had a squirrel-cage blower
(sucker) mounted under one end of a bench. This blower was salvaged
out of what had been one of those Jenn-Air type cooktops. I ran a 5"
sheet metal duct along the back of the bench and had inlets to it
for buffer, grinder etc. Each machine lived in a box, open at front
for access and with outlet at back into the exhaust duct. The
fittings; elbows, tee’s etc, can be found at heating suppliers. A
pair of tin snips and some sheet metal screws are about all you need
to adapt these to your needs.
The upgrade I am planning is an adaptation of a system I invented to
deal with another problem entirely. We live with a large family of
cats and a few years ago we moved from our large country acreage to
a house in the big bad city where we would not want our cats roaming
free. Thus the use of the indoor catbox escalated exponentially and
also the accumulation of dust and odours therewith associated. What
to do? I had placed the box under a counter in the laundry room,
curtained off the entry to the area, but that just concentrated the
The solution - Under the counter I installed one of those heat and
motion detector lights you see often installed outside houses and
garages. These have two light sockets. I removed one of the lights
and ran the wires from that light to a bathroom exhaust fan which
vented outside. Thus when a cat entered the area it activated light
and exhaust fan which ran on for about 12 minutes after being
activated - long enough for the cat to finish his business and cover
it up. This was also a great help to the humans who had to get down
and scoop the clumps out twice a day - plenty of light and no dust
or smell in your face.
Now I am going to install a similar arrangement with my buffer so
that I don’t have to turn on the exhaust fan (and then remember to
turn it off again) every time I want to use the machine. When I
stick my hands within working distance of the machine, a motion
detector will turn on a light and the exhaust fan automatically.
That’s my fantasy. Again, when I am done it will turn off
automatically fairly soon (the time delay is adjustable) and won’t
be sucking heat out of the shop if I get trancy and forget to turn
What I would do differently if I can find the parts. I’d like to
find a couple of those Jenn-Air or similar cooktops. When you remove
and discard all the burners what you have left is a wonderful sturdy
stainless steel pan - about 20" by 30" and a few inches deep - with
a flange around the edge for easy mounting into a benchtop. At the
bottom of the pan is the exhaust fan -also a drain hole or two into
a reservoir to catch any liquid spills or drips. Very tidy. Instead
of removing the exhaust fan, discarding the rest of the cooktop, and
cobbling together all that ductwork as I described above - I should
have left the fan attached and installed the whole pan into the
benchtop. I could then cover the whole top opening (where the
burners used to be) with a sturdy screen to catch dropped pieces,
set the buffer right on top of that, and have a downdraft extractor
right there in the benchtop - much easier!
What else I would have done differently if I only had a brain - I
would have paid a whole lot more attention to things like dust,
noise, etc when I was an invulnerable macho young hero. Some damage
has been done while I took my sweet time to learn about these
Marty in Victoria where I just put up a few Xmas lights - What a
handy guy, eh?