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Coolants for machining PMMA

What is the best coolant to use to machine (diamond turn) Polymethyl Methacrylate (PMMA)? We are using mineral spirits but they are hazardous to your health, therefore, we want to use something that is not life threating and something that will not harm the material.

Thanks,

Ruth Jones
- Huntsville, Alabama
2003

Have a conversation with your nearest machine tool sales rep. There is a possibility that you could get by with soapy water with a few % glycerine as a rust inhibitor.

James Watts
- Navarre, Florida
2003

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Well, first of all, plastic doesn't rust! I machine PMMA and I use an air compressor nozzle to cool pieces. I've also used dish soap 30% and water 70%, the soap contains glycerin which helps to adhere to cutting surface and keep cutting cool. Contact lens cutters use air blast to cool parts during cutting at 20,000rpm, with diamond tools, so it must work! If you air cool, use a clean, filtered air line to prevent the parts from "shot" by debris. (Makes a nasty crater)

Good Luck!

Jeff Swayze
Hole Joy! - Kelowna, B.C., Canada
2003