Know a good SCM DE method ?

[Jake Darvall]

I'm setting up a new workshop and I want to keep the SCM area clean.

The small bag that comes with it of course is inadequate.

Thinking to just suck from the port thats built into the machine and be happy with that , but I think a lot of dust is deflected away from there, and the port seems too small.

I usually have a backing board attached for cleaner cuts, but I'd say it probably make dust extraction harder. Imagine a lot of it would just bounce off the backing board.

appreciate any ideas. I'm about to put it in the too hard basket and move on.
:)

[Mike Cutler]

Jake

Most of the solutions I've seen involve some sort of a box built behind the SCM with a duct collector port in the bottom of that box. This way as the material is discharged to the rear, the box acts as a common plenum and captures and directs the debris to the dust collection pickup.

[John Keeton]

Jack, here are a couple of threads - http://www.sawmillcreek.org/showthread.php?t=74489
http://www.sawmillcreek.org/showthread.php?t=19936&highlight=Downdrafter

I ended up using a box similar to the one Chris Rosenberger used, with a 4" flex coming out of the top just above the exhaust on my CMS. Using a sliding SCM would seem to complicate that arrangement, but the idea is to get rid of the fines at the moment of cut. My arrangement does that very well. I still get heavy dust that settles behind the saw, and I periodically just reach back and pick up a couple of handfulls and toss it up to the port, into the DC collection. Seems to work fine.

I would think the downdraft idea would be best, but it didn't suit what I had already done. If I were planning from the get go, I might consider building a station for the saw, over a downdraft setup. Most of my heavy dust is thrown on the floor of my box, and if my DC port were there, I think it would take most, if not all, of it. Good Luck!

[Joe Scharle]

Piece of rolled cardboard has been working for me for years. Now I see Festool is doing something similiar.

http://www.ncwoodworker.net/pp/data/194/thumbs/SCMS_dust_chute_001.JPG (http://www.ncwoodworker.net/pp/data/194/SCMS_dust_chute_001.JPG)

[Bill Arnold]

Here's my setup:

http://bbarnold.com/images/shop-ga/09gMSBench.jpg

http://bbarnold.com/images/shop-ga/09hMSBench.jpg

[John Keeton]

Bill, I like that! I may get around to modifying mine and steal your design. I had my CMS set up prior to putting in my DC, and really should have redesigned the setup to function better, but was absorbed by the DC install.

I assume you get good collection? What about the small cutoffs that drop, do they get picked up?

[Bill Arnold]

Bill, I like that! I may get around to modifying mine and steal your design. I had my CMS set up prior to putting in my DC, and really should have redesigned the setup to function better, but was absorbed by the DC install.

I assume you get good collection? What about the small cutoffs that drop, do they get picked up?John,

Small cutoffs get sucked right into the pipe at the bottom of the chamber and wind up in the DC bin. When cutting something like MDF, I can see the cloud of fine dust puffing out a bit, but it is drawn back into the plenum immediately.

In my case, the entire chamber was easy to assemble because it's on a wall between sections of my shop. There's more information on my website under "Shop Tour" and "Miter Saw Bench".

The only additions I want to make is: A. some baffles on the sides and top inside edges of the upper chamber to reduce the amount of dust puffing out; and B. a chute angled from upper left to lower right in the lower chamber to funnel the chips and dust to the DC pickup better.

[John Keeton]

Bill, could you address A. by running another 4" port up to the top box? Don't know what your DC run looks like. I have a 4" coming out of the top of my box, which is similar to yours, and it grabs the fine dust immediately. I barely can see any when I make a cut. It is the heavy stuff that remains for me and the bottom chute idea looks like the answer. Maybe leave my top port as is.

[Bill Arnold]

Bill, could you address A. by running another 4" port up to the top box? Don't know what your DC run looks like. I have a 4" coming out of the top of my box, which is similar to yours, and it grabs the fine dust immediately. I barely can see any when I make a cut. It is the heavy stuff that remains for me and the bottom chute idea looks like the answer. Maybe leave my top port as is.John,

I don't have a major problem with fine dust around the top chamber, but your suggestion would eliminate a lot of it. I've been so busy with other projects that I haven't made the final DC piping to the MS. I'm still using a temporary flex to the bottom chamber. The final configuration will come from the ceiling/wall junction and run beside the upper chamber of my MS box. I could easily bring pipe to a wye and split the pickup between the upper and lower chambers.

[Joe Jensen]

John,

Small cutoffs get sucked right into the pipe at the bottom of the chamber and wind up in the DC bin. When cutting something like MDF, I can see the cloud of fine dust puffing out a bit, but it is drawn back into the plenum immediately.

I put some 1/4" wire cloth over the port in the back of my RAS to keep small pieces from getting sucked up. I was concerned that they could create a blockage in the duct.

[Bill Arnold]

I put some 1/4" wire cloth over the port in the back of my RAS to keep small pieces from getting sucked up. I was concerned that they could create a blockage in the duct.Joe,

That's a good thought -- something to consider, for sure. The cutoffs I'm talking about are mostly thin slivers or slightly larger pieces. Pieces with any real size stay on the MS, so I haven't been concerned. It would be easy enough to add some hardware cloth over the pipe before sticking it in the DC hole.

[Jake Darvall]

Thanks kindly for all the advice. Much gained from your posts. ta.