Acrylic Cutting Help

[Tenson]

I don't think it is just the feed and speed, since the X axis direction is fine at the same speeds. I suppose increasing feedrate might reduce the need for better extraction though? If I push feedrate too high without increasing RPM of course the bit will deflect or break, it is only 3mm dia.

I can probably improve dust extraction (for one, I emptied my vacuum!). I'll have a play and let you guys know how I get on.

[Tom J]

Just broke last carbide single flute 1/8" 3.175mm bit doing 700mm/min at 10.000 rpm, 600mm/min was ok but still poor finish.

[Rye]

I usually cut acrylic with 1 mm passes using a 3.175mm single-flute @ 1050 mm/min - somewhere between 10000-13000 rpm (i think). Will be cutting some tomorrow. Will post RPM here.

[Tom J]

I usually cut acrylic with 1 mm passes using a 3.175mm single-flute @ 1050 mm/min - somewhere between 10000-13000 rpm (i think). Will be cutting some tomorrow. Will post RPM here.

I follow 50%+ rule of DOC which was 2mm in for 1/8" will try less. Going to buy decent Trend bit 1/4" 6.35mm

[Rye]

I follow 50%+ rule of DOC which was 2mm in for 1/8" will try less. Going to buy decent Trend bit 1/4" 6.35mm

Cut some 4mm acrylic today using a 4mm shank/3 mm dia cut single-flute shop-apt bit. Did two passes @ just under 2mm on each with a finish pass. Feed rate 1200 mm/min with spindle speed around 13200 rpm (220 hz). Cut fine leaving a nice finish (just a couple of tool marks on one side.) Not saying that's the correct or optimal speed, but it worked for me. Usually I stick to smaller passes because I have a habit of not properly sticking/securing the acrylic to the spoil; and there's nothing worse than spending ages engraving acrylic just to have it lift from the table when cutting :)

[magicniner]

Several mentions of "Climb V Conventional" in this thread.
If you are cutting a slot when profile cutting a part there is no climb and conventional, the cut direction only affects the deflection direction toward or away from the part, the cutter is cutting both climb and conventional in alternate halves of it's rotation.
Climb V Conventional only comes in when the cutter is engaging less than 100% of it's width in material,

- Nick