On 6/12/2019 5:26 PM, pyotr filipivich wrote:
Meanie on Tue, 11 Jun 2019 20:34:38 -0400 typed in
rec.woodworking the following:
I'm tired of the sawdust induced filter in my shop vac and decided it's
time to get a better filter, which I assume there isn't anything to stop
sawdust clogging, or make a cyclone separator. Thus, anyone have any
suggestions for a filter or easy plans for a cyclone separator?

Easy plan is that somewhere upstream of the filter, put a "box"
which is much larger than the hose, where in the 'larger' chunks fall
out. With baffles you can cause eddies in the air flow which will
allow more dust to "fall out".

That's what I did with my regular dust collector. That was way before
the internet telling me it wouldn't work without huge horsepower, and
all that stuff.

I figured when the high pressure/velocity in the small intake hose hit
the 40 gallon drum (essentually a 22" hose) the pressure drop would
cause the sawdust to drop out into the drum. Next, I figured the intake
hoses should direct the dust in a circular manner, around the outside of
the drum, causing the heavier stuff to fall to the sides. This has
served me well over the years, and I hook all my large machinery up to
it w/o problems, including jointer, planer, TS. Almost no sawdust gets
to the collector which is about 25 feet away, though all sorts of turns
and twists.

http://jbstein.com/Flick/dc1020457.jpg
http://jbstein.com/Flick/dc1020458.jpg

I have since these pictures added a 4" hose for my 15" planer, and 3"
hose for my 6" jointer. It never clogs up, but the collector does get
fine powder in it and needs cleaned a couple times a year. I don't hook
my 48" belt, 10" disk sander to it anymore, but just use the shop vac as
that fine powder does get through more than I'd like.

This collector doesn't have a 200 hp diesel engine powering it however,
and would be what most would consider under powered, but it sure works
and that's what I care about. My collector is high volume, low pressure
whereas a shop vac is low volume high pressure.

Or buy a small cyclone unit to do the same thing.

I've seen lots of Youtube videos of these, including the Thein baffle,
and they don't seem to work any better than my system, some a little
worse. I've been thinking of making a smaller setup like this for one
of my shop vacs, but really, I don't empty them but once it a while
since most of the work is done by my big collector. The fine dust
(powder) you get from sanding is going to get to your filter without
Herculien effort to remove it first. That's why they have filters on
them. My shop vacs can handle the dust on the filters rather well, and
I can easily fill up the small 5 gallon can with dust covering the filter.

Also, my pictures show el fittings in the drum, but I noticed my shop
vacs just have a straight pipe with an endcap, and a hole/notch cut in
the side to direct the air around the outside of the drum, that would be
easy to implement as well.

--
Jack
Tolerance is the virtue of the man without convictions.