WoodWorkCalc guide
CNC Feeds and Speeds for Acrylic: Avoid Melting and Chipping
Acrylic behaves differently from wood. Heat management, chip clearing, workholding, protective film, and bit geometry all influence whether the edge looks clean or melts back into the cut.
At a glance
The shop-ready workflow
- 1
Control heat with a disciplined starting point
Define the inputs before you commit material or time.
- 2
Protect the sheet and hold it flat
Use the calculation to make the decision visible and repeatable.
- 3
Inspect the chips and edge after each change
Turn the result into a protected next action for the shop or client.
Calculator explainer
See what the tool is doing
Bit + material + RPM + feed
Start with controlled chip load
A safer test-cut setting
CNC Speeds and Feeds →RPM + flutes + chip load
RPM × flutes × chip load
Starting feed rate
CNC Feed Rate Calculator →Setup + run time + tooling + material
Machine and labor costs + profit
A repeatable CNC job price
CNC Cost Calculator →Control heat with a disciplined starting point
Use the material and tool manufacturer's guidance, then test conservatively. A setting that creates chips and clears them can behave very differently from one that rubs, heats, and melts the edge.
Protect the sheet and hold it flat
Use an appropriate holding method and consider the protective surface where suitable. Avoid a setup that lets a thin sheet chatter, lift, or release near a final cut.
Inspect the chips and edge after each change
Watch for melting, welding, chipping, chatter, and surface scratches. Change one variable at a time and document the successful combination for that exact acrylic and bit.
Common questions
Answers before you start the job
Why does acrylic melt on a CNC?
Heat can build when the bit rubs instead of making and clearing chips. Bit geometry, feed, RPM, depth, tool condition, and chip clearing all affect the result.
Can I use wood CNC settings for acrylic?
Do not assume so. Acrylic has different heat and chip behavior. Start from material and tooling guidance, then test on matching scrap.
Should I leave protective film on acrylic?
Follow the material supplier's guidance and test the full process. The film can protect surfaces in some operations, but it also changes what is present at the cut.