When you choose the WRONG bit for acrylic


Your depth of cut may be too deep , I use the same bit just slow down a bit and don’t go so deep.

In general, its best to expose as little as possible of the tool as possible to reduce stickout. Longer stickout = more tool deflection = lower edge quality and greater chance of tool breaking :slight_smile:

PS - dont clamp down on the tool cutting edge either :slight_smile:

For plastics I use a 3mm 1F bit with a 6mm long cutter edge = only like 8mm of the tool is exposed.

Good to know. I realized right away that with that amount of tool stick-out, I should have cut the depth in half and sped up, not slowed down. Even cruising at 65ipm, the acrylic melted around the bit and contributed to snapping it.

I had a brain fart on my bit choice because I programmed this in Fusion for a 2F and then ran the Gcode through Easel without remembering that I have a sweet 1F Onsrud upcut bit that I usually use for cutting acrylics.

Once I snapped this bit, my memory jogged and I put in the Onsrud. After that, it cut like butter at full depth (.086" acrylic with a .125" 1F bit). Totally agree with you on tool stick-out and sadly, I knew better (being a machinist) but pressed my luck anyway.

Doh! I like the “F%$#*” as soon as it breakes… although I feel your pain.

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