[jetvich]

Hello forum,

I work at a place that uses a lot of plastics (.0625”-1.0”) for custom brackets and gears. I'm currently looking for some way to fixate my part and eliminate lifting. I'm open to any suggestions…this problem may be due to wrong tooling or something, I really don't know. I'm new to this profession. I'm currently using double-sided carpet seeming tape, but it is extremely expensive and it gums up the bits and the part. Any suggestions would be grateful. Thank you.

[bluejay_ca]

Most anything can be clamped down, it's tried and true. Use some imagination.

[teamtexas]

Have you looked into using vacuum clamping? Check out this link http://www.nemi.com/square_slider_pod.htm They have some great ideas. If you make the same pieces over and over you could make some special jigs for each.

Dan

[bluejay_ca]

I had considered vacuum for myself but discarded the idea because I am primarily a wood guy. Good for a smooth, non porous area though.
Having used vacuum to hold parts on my robots at work I have much experience with such. The major problem is that although it may lift a 50 Lb. part any jerking motion and the part tends to slide off. If you use the vacuum to hold the part down then provide some dowel pins or other mechanical means you may have something.
Vacuum generators are very easy to make, using compressed air as the power source.

[Clockwork]

Most of the parts I make are in wood. I use drywall shim (gray cardboard) sprayed on both sides with 3-M spray glue to attach the workpiece to the sacrificial board. A small tap with a chisel separates the laminations when the cut is finished.

Removing the remaining cardboard from the workpiece is easy. Dab on some mineral spirits with a brush and about 30 seconds later it peels right off. The remaining sticky residue can be cleaned off with a small amount of mineral spirits on a rag.

The MS has no effect on any wood or plastics I've worked with. In wood, it gives a preview of what the piece will look like after a clear finish is applied.

Also, many people don't realize that up-spiral bits exert a considerable lifting force on the workpiece.

[ger21]

Having used vacuum to hold parts on my robots at work I have much experience with such. The major problem is that although it may lift a 50 Lb. part any jerking motion and the part tends to slide off. If you use the vacuum to hold the part down then provide some dowel pins or other mechanical means you may have something.

I made new pods for our machine at work from Lexan, and used this tape around the perimeter to keep parts from sliding. It's thin, and very hard, so it doesn't noticeably compress under vacuum. These guys are great to deal with, and have al kinds of products for vacuum fixtures.
http://www.allstaradhesives.com/acce...s_zgrabber.php

[martinw]

Most of the parts I make are in wood. I use drywall shim (gray cardboard) sprayed on both sides with 3-M spray glue to attach the workpiece to the sacrificial board. A small tap with a chisel separates the laminations when the cut is finished.

.

Dear Clockwork,

That method works well. I used it to attach the workpiece to a woodturning lathe chuck where the cutting forces are considerable. When you are done, you split the pieces apart down the card or paper.

One thing you should do is put a small rebate in the sacrificial board so that you can get the tip of your chisel under the edge of the workpiece so that you do not damage it when you come to lever the bits apart.

Best wishes,

Martin