Drilling 1/8 plexiglass

[toddmaci]

I have a request to drill several pieces of 1/8 inchthick plexiglass. Hole size is yet to be determined but I think 1/4-1/2 inch. I am seeking guidance on bit types , feed and speed and any other tips.

Thanks in advance,

Todd

[Brady Watson]

My advice would be to not drill it at all. Use a smaller bit, like 3/16" spiral-O and do an inside profile cut with a spiral ramp.

You could use a plastic drill bit, but you'd have to go another 1/8" deeper to drill it all the way and that often creates swarf under the material that causes your vacuum/hold down to fail.

-B

[nailzscott]

I cut some 1/2" holes in 3/16 acrylic a couple of months ago. What worked best for me in this case was a 1/4 single flute bit. Spiral bit and double flute generated to much heat and ended up melting fragments back together. My router and cut speeds were slow too. I think feeds were around 1 to 1.5 in sec.

[tuck]

Plexi can and will expand and contract outdoors. Cut/drill your holes slightly larger than the diameter of whatever fasteners are going to be used to prevent cracking, assuming that the holes are for fasteners and the panels are for outdoor use. The idea is to let the panel(s) float a little bit in the heat/cold.

[curtiss]

:) Swarf, also known as turnings, chips, or filings, are shavings and chippings of metal — the debris or waste resulting from metalworking (http://en.wikipedia.org/wiki/Metalworking) operations including milling and grinding. It can usually be recycled (http://en.wikipedia.org/wiki/Recycling), and this is the preferred method of disposal due to the environmental concerns (http://en.wikipedia.org/wiki/Environmentalism) regarding potential contamination with cutting fluid (http://en.wikipedia.org/wiki/Cutting_fluid) or tramp oil (http://en.wikipedia.org/wiki/Tramp_oil). The ideal way to remove these liquids is by the use of a centrifuge (http://en.wikipedia.org/wiki/Centrifuge) which will separate the fluids from the metal, allowing both to be reclaimed and prepared for further treatment.

The chips can be extremely sharp, and this creates a safety problem, as they can cause serious injuries (http://en.wikipedia.org/wiki/Laceration) if not handled correctly. Depending on the composition of the material, it can persist in the environment for a long time before degrading. This, combined with the small size of some chips (e.g. those of brass (http://en.wikipedia.org/wiki/Brass) or bronze (http://en.wikipedia.org/wiki/Bronze)), allows them to disperse widely by piggy-backing on soft materials and also to penetrate the skin as deep splinters (http://en.wiktionary.org/wiki/splinter).........

[toddmaci]

Thanks for the tips.

Todd

[gundog]

Like Brady said I would not drill it I would mill it. Careful cutting too slow with plastic it can reweld cutting too slow can cause too much heat just like cutting too fast. IMHO the best thing to do is get a bit designed to cut the material you are working with most good bit manufacturers will give you a recomended chip load once you have that you can calculate the proper speed and feed. The chip size is critical the chip carries away the heat from the bit.

http://www.onsrud.com/xlink/xlProductDetail&xlProductDetail_xcrit1=63-706

http://www.onsrud.com/xdoc/ChipHardPlastic

I picked the 1/8" 63-706 for example it says .006-.008 chip load this is a single flute cutter. I did the calculation shown and came up with 18000 RPM feed rate 1.8 inches a second or 108 inches a minute.

Mike