Dust collection for 3d

[windsor@muskoka.com]

I've been doing more 3d cutting recently . The biggest problem I have is dust collection . When I'm machining a part out of a block that is 3"-4" thick the regular dust sweep doesn't cut it . ---Has anybody tried to make a down draft table ? --or any other ideas ? Thanks Mike Windsor

[gittel]

Yes, the regular dust sweep is only for flat material. I also am doing 3D cutting and had the same problem, so after a bunch of experimentation, I built a dust shroud out of sheet metal. It works fairly well when cutting 3D material. The shroud is attached directly to the bottom of the PC router, so it rises and falls as the Z axis moves up and down. The air is pulled up three channels which are 1 inch wide by 7 inches long by about 24 inches high. At the top is a pyramid which combines the three channels into a 5 inch dust collector port, which is then connected to a 1.5 horsepower dust collector. The advantage of this system is that as the dust is thrown away from the bit by centrifugal force, it is then sucked up the channels which surround the bit about 4 inches away. For short bits it works well without any further dust skirt, but I'm trying various brush and rubber skirt material in order to lower the zone of suckage. The 3.25 hp PC router fits inside the shroud. I'll try to post some pictures to www.twocats.com/shopbot.
Mike

[shuttle]

Ive had success keeping the stray dust contained by using 8" ducts along the 8'length of the table, sucking air down through a 2 stage furnace filter setup under the table. I use wood to block intake sections and concentrate the airflow in the area of cutting.


4900

[bjwat@comcast.net]

I checked out the pics....Looks good Mike!

I am in the process of redesignng the dust collector with the Colombo. It hits the inside of the legs when it goes to cut anything that is within 4" of either edge of the Y axis....

I didn't want to stop the process while milling my spoilboard so I had to mill it with out it. I am using 4 sheets of 3/4 X 5'X 8' MEDEX (5' X 16' table)...and I have never seen so much fine dust in all of my life! It is ALL OVER EVERYTHING!!!

If only someone saw me chasing the router around with the shopvac! LOL! I filled that thing up 3 times!

I am going to do a similar setup on mine and see how it goes. Dust collector is on the list & I am sure that I will have to cut MDF in the future.

Brady

[gittel]

You should get the book "Woodshop Dust Control" by Sandor Nagyszalanczy. MDF is sawdust and glue. The ShopVac can capture some of the visible dust, but it is the invisible dust and glue pollutants which cause the health problems. You should use a good respirator, especially when cutting MDF.
Mike Gittelsohn

[sheldon@dingwallguitars.com]

I've given up trying to capture dust at the source. I bought a 3000 cfm barn fan and some 1 micron shaker felt and am designing a 150 sq ft ambient air filter to stick at one end of the machine. Other *cough* projects *cough* have gotten in the way *cough* of finishing this *cough* but I hope to *cough* have it done soon.

[rgbrown@itexas.net]

Sheldon,

I've often thought one could build a large V-shaped tray under the ShopBot and put the "Fan" and filter there. The dust would be drawn to the sides and under the table. Chips would occasionally be raked out through a door and into a bag or six.

Ron Brown