This article is from the Woodworking FAQ Collection 2, by multiple authors.
From: email@example.com (Stuart Friedberg)
Date: 10 Sep 91 22:47:16 GMT
References: <firstname.lastname@example.org.HP.COM> <email@example.com>
firstname.lastname@example.org.HP.COM (Dan McGee) writes:
>I want to use some kind of dust collection system
>to get rid of the maximum amount of sawdust possible but I don't know
>where the majority of the sawdust is comming from.
email@example.com (Howard Cohen) writes:
>I think its safe to say that at least initially the sawdust is eminating
>largely radially, in the same plane as the blade. It probably spreads to the
>left and right of the blade (again, radially) in decreasing distribution.
This might be useful, but applies to a radial arm saw, not a table
saw. I went to the hardware store and bought a 4" to 6" increaser, a
tapered sheet metal tube about 10" long. Using a disgusting hack, I
mounted the 6" end next to the column on my small (Ryobi RA200) radial
arm saw right in back of the blade when the carriage is pushed back.
My new dust collector gets plugged into the 4" end.
When crosscutting (which is all I use the RA saw for), almost all (well
over 95%) of the dust shoots in a distinct stream directly down the
gullet of the increaser. A little bit stays on the table, where a
brush can flick it over the fence and into the air stream, and a little
bit more misses the increaser and lands behind the saw. Very little.
I don't think this would work with a shop vac instead of a dust
collector. BTW, the RA guard has a built in hole for a 1 1/4" shop
vac, mounted tangent to the blade inline with rotation at the top, and
nearly nothing comes out of its own accord.
I built a plywood box with a 4" metal vent on top to replace the chip
deflector on my 12" planer. Instead of dumping the chips on the
outgoing wood and the floor, the machine now shoots them directly into
the maw of the dust collector. A very few shoot out the front of the
planer, and a bit out the sides, but not very much.
What's interesting is that the dust collection box for the planer
surrounds the workpiece and is a fixed distance from the cutter, while
the increaser stuck behind the radial arm saw is, in comparison, narrow
and far away from the saw blade. Yet, each work very well.
(Howard Cohen, again)
>Also, you may be able to achieve a modest air current through the
>various openings toward the collection point, which will hopefully draw
If you're using a dust collector instead of a shop vac, the air
current will be quite respectable, and probably keep the inside quite
clean, even if all you do is block off the bottom with plywood and
stick in a d.c. hose. I don't know if that will have any impact on
the dust generated above the table, but it should suck up any chips
that get carried below the table by the blade.