Any innovative ideas for cutting acrylic flat sheet into discs?

[SRT Mike]

I am putting together some prototype parts - I have some sheets of 1/8" acrylic sheet, 12" x 12". I need to make about 20 discs, 1.30" in diameter.

I have various tools at my disposal - CNC lathe, CNC mill, drills, sanders, etc.

If this product goes to production, we will get these laser cut or water jet cut, but I am scratching my head trying to come up with a way just to make a few *easily* that won't scratch up the surface and make them look bad.

You guys have come up with some very innovative ideas before - any suggestions? Only thing I've come up with so far is trying to hot-glue a square of the acrylic to a piece of sacrificial stock, routing it on the mill, hoping the protective paper is stuck to the acrylic well enough to stop it flying around, then pulling the paper off it once I'm done.

There's gotta be an easier way... I just lack the brainpower to think of it

[Gary55Ford]

We cut .020 acrylic were I work, we use double sided carpet tape to hold it down on a piece of wood and c-clamp the edge. Then we put it in the cnc mill vise-works great

[Geof]

I have done exactly this by rough cutting the discs on a band saw. Then holding them between a piece of bar faced off in the lathe and a cap held in by the tailstock. Provided you take a gentle cut the tail stock pressure will clamp the acrylic against the end of the bar tight enough to face it off.

If I remember correctly you have a gorilla of a lathe, you should have no problem holding the discs to turn the OD.

[cam1]

Nice: I call Geof's method pressure turning, whe sometimes stack a few pieces together, and turn in one shot. Just make sure to use as large a disc as possible (finish OD-1/2") on both sides, and clamp the tailstock tight.
Works great and it's fast.

[cam1]

PS: If you have a live center with various exchangeable centers such as flat serrated plate, it serves nicely to hold the cap in place.

regards

[skottc]

You're on the right path. Use something like mdf and use your mill. Use double sided tape(3M 4032) to hold down. The paper or film on the Acrylic is designed to hold while lateral force is applied. Conventional cutting with as high a rpm as possible. We laser cut and machine 100's of thousands of similar
parts. When routing, if we are just making just a few we use tape, on large production we use vacuum tables to hold down parts.

Scott
www.ocip.com

[MFassler]

clamp it too a piece of aluminum or something similar in your cnc mill and interpolate the OD
and cut almost full depth leaving like .020 or some thing so they dont come flying out and you will just have too do some minor deburr too em and your done. vacuum fixture works well too.