CNC Cut Simulator
Ride the bit. Dial the feeds. This is every feeds-and-speeds mistake you'd normally pay for in ruined boards and snapped bits, running live in your browser. Drop the feed until it rubs and burns. Push it until it chatters. Find the hum in the middle. That's the skill.
Ready to make some chips?
Sound on. The whole point is hearing the difference between a happy cut and an angry one.
What You're Seeing (and Hearing)
Rubbing
Feed too slow for the RPM. The flutes skate instead of biting: dust, a thin squeal, browning walls, and a bit heating toward dull. Fix: feed faster, drop RPM, or fewer flutes.
Dialed in
Chipload in the safe window. Real chips carry the heat away, the cut walls come out clean, and the sound settles into a steady hum. This is what you're listening for at the machine.
Chatter
Bites bigger than the machine can hold rigid. The bit bounces, walls come out wavy, and the sound turns into a growl. Keep pushing and the bit snaps. Fix: slow the feed, raise RPM, or more flutes.
The physics under the hood
Chipload = feed rate ÷ (flutes × RPM)
The simulator runs the same safe-window data as our chipload chart. When you're ready for real numbers on your machine, the feeds & speeds calculator has presets for 24 hobby CNCs.
Simulator FAQ
What happens if my CNC feed rate is too slow?
The flutes stop taking real chips and start rubbing. Rubbing makes heat instead of chips, so the bit dulls fast and the wood burns. In the simulator, drop the feed rate and you'll hear the pitch climb to a squeal, see dust instead of chips, and watch the cut walls turn brown.
What causes CNC chatter?
Chatter happens when the bit takes bigger bites than the machine can hold rigid, so it bounces off the cut and re-cuts its own vibration. Chipload is too high: the feed rate is too fast for the RPM and flute count. Slow the feed, raise the RPM, or use a bit with more flutes.
What is chipload?
Chipload (feed per tooth) is how far the bit advances per flute per revolution: feed rate divided by RPM times flutes. It sets the chip thickness. Too thin rubs and burns, too thick chatters and snaps bits. The simulator computes it live from your settings using the same chipload table as our calculator.
Is this CNC simulator physically accurate?
It's stylized on purpose, but the relationships are real. The safe chipload windows come from the same data as our chipload chart, and every effect moves in the true direction: slower feed means rubbing and burning, higher feed means chatter and eventually a snapped bit. Your machine's exact numbers will differ, so always test on scrap.