Luca Nervetti milling some acrylic with ChiliPeppr.

@Luca_Nervetti milling some acrylic with ChiliPeppr. I do a lot of acrylic too and it’s hard to not get it to melt at the end mill. Looks like he nailed it.

@jlauer ​ do you use cast or extruded acrylic?

Hmm. Sadly I don’t know if it’s cast or extruded. Maybe one melts less than the other?

Chemically they are two different materials… And one has an extrusion grain while the other has a crystalline structure… Not sure if it makes much difference with the CNC only used extruded… But with the laser you get a frosty engrave with cast and a glossy/glassy engrave with extruded

I have both on hand and will need to run CP on some wood, will give a try next time that machine is fired up

Did you try using alcohol mist or plain air for cooling?

I have an odd way I deal with this on my mill but it may be helpful John. It takes test cuts and scrap material but works.
I have a RPM reader device and a manually controllable spindle. I do test cuts in one direction at set speed and manually adjust the RPM until I hit a speed that cuts without difficulty but doesn’t burn. I then read the RPM with the doobery and set the output PWM for approximately that.

I use air to cool it, but maybe something more aggressive like mist could help. I was taking 1 mm deep depth of cuts in slots and had to dial that back to 0.5mm. I can take 4mm depth of cut if i’m doing an adaptive clearing. I’m learning the nuances of this material.

Hi to all :slight_smile: this kind of material is very easy to cut. I have also other different pieces of I think is plexiglass and some time it’s melt on the bit. I found that if I use a 3mm double flute end mill I can cut that with no melting. I will do a video comparison of bits and material.