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Dwayne Cook
11-12-2007, 3:50 AM
Hi SMC

I have a company CNC routing some 1/8th in plywood for me and we have been having trouble with keeping it sucked down to the table.

they have a KOMO machine with a table about 5x10 feet they are CNCing
it for me and then I laser engrave it. I guess with such thin Material and the way it warps cutting small stuff is hard.

If anyone has some advise please tell me. there giving me a good piece price and I feel if its too much for them they wont keep doing my orders.

Dwayne Cook
Epilog 45w & 35w

David Epperson
11-12-2007, 12:30 PM
I know of at least one machine shop that uses either a vacuum pump or double sided tape to hold thin stuff to the table.

Neal Schlee
11-12-2007, 2:21 PM
Lot's of variables to deal with here. How big are the parts? Sounds like they're using a high volume vacuum setup, great for sheet stock except when cutting small parts. They may also be loosing vacum thru the ply as it is only .125" thick thus limiting the hold down pressure. There are other options, such as a custom vac. carrier board using sheet foam from AllStar or tabbing might be also an option. They might be able to slow down the cutting speed as to limit parts from shifting, or add another pass, i.e. use a onion skin. What bits are they using, sometimes using a downshear bit helps, it tends to pack the chips into the kerf behind the bit as it cuts thus helping to keep the parts from shifting? Maybe Mike K. will chime in, he's cnc cut a lot of birch ply. I've cut quite bit but only .5" ply

Neal

Michael Kowalczyk
11-12-2007, 5:00 PM
Thanks Neal for thinking of me.
Hope all is well way up there. I already posted on Dwayne's other post in the laser forum. If you read it you'll see we are pretty much on the same page. I would probably stay away from a downshear though so you don't have blow out on the backside unless he has REAL GOOD vacuum. I would try a 2 or 3 flute straight bit. There maybe other limitations we are not aware of that would force us to use a larger radius bit which would limit the amount of flutes. If Dwayne can post the item(s) without giving away trade secrets we could be more specific or maybe there will be enough info here to help him.

Dwayne Cook
11-13-2007, 2:18 AM
Thanks for your help

i tryed to lend some ideas to the company cutting for me. I think they got it under control.

If anyone has vendors that will do CNC cutting on the 1000 to 5000 piece range please let me know.

I am in Okla. but i travel all across the country.

Dwayne Cook
Thanks for the help

Michael Kowalczyk
11-13-2007, 2:25 AM
Dwayne,
This is what I do Full time. The laser business is part Time. You can PM me the files or your phone# if you want to discuss it further and or get a quote. Thanks,