I’m working on learning how to use the CNC, and I’m having a hard time figuring out the proper chip load, as well as the step-over and depth of pass that I can use.
I got a 1/4" inch 4 flute cutter off amazon hoping to be able to rough more quickly. I set it to 2mm stepover, 3mm depth and 500 mm/s. This is sort of working but I’m getting quite a bit of burning and more dust than chips.
For chip load specifically I looked at the guide here: https://www.cutter-shop.com/information/chip-load-chart.html. This recommends .009” - .011” for a 1/4 inch cutter. When I put that (0.22 mm) into Fusion at 12K RPM I get ridiculously high feed rate of 10K mm/s.
Is this just a sign that I shouldn’t be attempting to use this end mill on the snapmaker, or should I be doing something differently?
And yes, if you want to take .22mm / flute at 12,000 RPM with 4 flutes, then yes, you’ll have to travel at 176mm/s
Perhaps drop the spindle speed, and see if you can take a lower chip load without burning.
Minimum chip load can be recommended as low as 5% of the cutter radius, which would be .15mm for that cutter. At 6,000 RPM that would be a travel speed of 60mm/s, which is getting more reasonable. Not going to be able to get a lot of axial depth of cut with that.
You haven’t told us what wood you’re trying to work on. Makes a huge difference if it’s a softwood like pine or a hardwood like oak.
Also no idea what the bit you have from amazon is. You generally don’t need more than 2 flutes for wood. Doesn’t sound like the proper bit.
If you’re saying your step-down (depth per pass) is 3mm that is way higher than I’ve found to be usable on SM with any type of wood. .5 is my usual and 1mm my max if I"m pushing it.
As far as work rates somewhere between 400-800mm/m
-S
Great, thanks. The min vs. sec is the key thing I was missing for the math.
I’m cutting a piece of scrap wood left over from the shelving when my house was build, so I’m not sure what it is. Harder than pine. Definitely not oak. Maybe poplar or maple?