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mikefalkner
08-01-2015, 03:24 AM
I would like to use my CNC to sand the cut edges of 1/2” thick Baltic Birch plywood right after cutting out a piece before picking up the piece off the table. The work pieces are held down with screws and tabs. The cut is made by 1/4" compression bit, leaving over a slot of 1/4" wide to get some type of sanding bit in. So the question is: “What sanding bit would do this?”

I thought of Dremel’s 1/4” sanding bands, but they are thicker than 1/4" and will not fit into the cut slot. Also thought about removing the scrap pieces, leaving the cut-out desired piece on the table, but then there is nothing to hold the piece in place since the screws and tabs would be gone.

Has anyone solved this issue?

ger21
08-01-2015, 07:32 AM
I would forget about the idea of sanding with the router, for several reasons.

Even if you could find a sander less than 1/4", something that small wouldn't last long at all.

There's also the issue of the drum rubbing on the spoilboard. You wouldn't be able to get to the bottom of the part.

And there's also the issue of rpm. For sanding, I'd think that you'd want to stay below 1000 rpm? Maybe 2000 rpm max, depending on the diameter of the drum.

I've seen sanding heads for large industrial routers, but they were several inches in diameter, and were used on machines where the worpiece was supported with vacuum pods above the table.

You'd probably be better off using a spindle sander and hand sanding them while the CNC was cutting the next batch.

minicncuser
08-01-2015, 11:33 PM
Try on onsurd 61-082 1/4" (Solid Carbide One Flute Straight for Hard and Soft Plastics) We cut acrylic But have been cutting lot of plywood too 18000 rpm 150 inches a min one pass climbcut (conterclockwise) the cut we get is our finshed edge no sanding no edge banding

mikefalkner
08-02-2015, 01:05 AM
I want to thank both ger21 and minicncuser for their replies.

After reading ger21 comments, I was brought back down to earth. He comments are common-sense. Gee, wished I would had thought though the issues as well as he presented them. Many thanks.

However, minicncuser has a good idea -- get better bits to see if they reduce the need for excessive sanding.

Thanks for taking the time to reply.

Mike

minicncuser
08-05-2015, 07:37 PM
Hey just cut some today (62-733 Onsurd 3/8 down cut) Dull from cutting acrylichttp://www.cnczone.com/forums/attachment.php?attachmentid=288938&stc=1 Right off the router no sanding