Originally Posted by
Dennis Leahy
... I think what Bill is trying to tell me is that I won't see any dust. I think what Alan is trying to say is to underscore Bill Penz's words, and make me realize that I could have done better with larger ducting, and that there will still be invisible dust particles in the air. ...
Alan has been quoting Pentz's site almost verbatim - nothing wrong with that. There are good points about what both of them are saying but there's also something to be considered in real life situations. Experiences of other woodworkers in their shops should carry as much or more weight than speaking to the pure engineering aspects of a DC system.
In my case, I get excellent collection from the 4" port at the bottom of my tablesaw cabinet. I've added collection above the blade as well. There is no cloud of dust around the saw. Now, when I ran duct to my tablesaw, I took 6" to a 6-5-4 wye under the bench behind the saw. The 5" side runs to a 5" blast gate only a few inches away from the 4" port on the saw. I did this so that, at some point, I can increase the port size on the saw. That modification has taken a back seat to everything else because I don't have the "cloud of dust" surrounding my saw.
For my miter saw, I have a 5" duct off a wye on the 6" main. It feeds to a 5" blast gate and 5" pipe runs to the bottom of my MS dust containment box. I stayed with 5" in this case because the side of the box is MDF that I could cut out easily. I can tell no difference in dust containment between having the 5" hard duct and a 4" flex that I had run to the containment box originally. When I cut a piece of MDF without the DC on, there's a cloud of very fine dust billowing out of the upper portion of the containment box and drifting around the room. With either the original 4" or the 5" I now have running to the box, the fines are drawn into the box and DC pipe immediately.
My system allows me to have multiple ports on a branch open simultaneously. Quite often, I'll have the MS and TS gates open as I work between them. I see no appreciable reduction in dust control in that situation.
You can see my overall duct system (as approved by Oneida) as well as certain details on my website by clicking on my name above, then clicking into my site.
Last edited by Bill Arnold; 12-07-2009 at 1:21 PM.
[SIGPIC][/SIGPIC] Bill Arnold
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