"Morris Dovey" wrote in message
...
On 1/15/2010 3:33 PM, Leon wrote:
Snip



Fine dust normally does not take up much space, it compacts well.
Would'nt
that be what you actually did find in your shop vac?

That would seem to be a reasonable guess, but I've been using a pair of
cyclone separators in series for almost eight years now - see

I can certainly see how that probably works better... with 2 containers
before the DC. I was referring more to how Brian pictures his set up. His
shows 1 single main collection bucket and a shop vac. I would assume that
what you find in your second bucket would be what Brian might find in his
shop vac.

The syatem pictured here, http://www.oneida-air.com/gorilla_landing.php
shows a main waste collection bucket and at the bottom of the pleted filter
a smaller container to collect the fine dust that does not get caught by the
cyclone.


Your set up would appear to be more closely described as a 3 stage vs. 2
stage collection system.




http://www.iedu.com/DeSoto/Misc/dustcoll.gif

for a photo - to collect dust from the CNC router with results that you
might find surprising: the first barrel traps all of the coarse stuff, and
the second barrel traps the /really/ fine stuff.

Actually, pretty much what I would have expected.


The surprising part is that the DC has _never_ been emptied and that there
is more dust on the outside of the bags than inside...

No doubt.

...and the main reason for the dust on the outside of the bag is that I
sometimes forget (but only for a very short while) to turn on the DC. )

Yeah, LOL.... I noticed yesterday as I was cutting with my BS that there
was dust flying out every where. Took me 3 seperate cuts brfore I decided
to see what was going on. I came to the quick conclusion that the 20' hose
running back to the DC probably should actually have been hooked up to the
BS rather than simply laying on the floor 5 feet away. The DC was sucking
its heart out and I was getting no pleasure, so to speak.