CNC Toolpath, bit diameter

No matter what bit I have selected Luban (1.5mm or 3.175mm), the tool path is exactly the same. Luban does not seem to be taking the tool head diameter into consideration, and the features of the design are all lost. The design has ample spacing for 3mm bit, but Luban plunges right on the path of the design, rather than the outside (when using the Fill cutting option). Short of using Fusion, how do I solve this?

Thank you.

PS. Even though the Snapmaker came with a 3.175mm Flat End Mill bit, Luban does not have that option included. I made my own tool with the 3.175mm diameter, but that doesn’t seem to make any difference.

It seems that I almost have to inset my design by the bit diameter amount to get the desired results. If that’s in fact the case, seems like a massive oversight on the part of Luban.

Luban will ignore whatever bit you actually put in, the density/interval is what you’re aiming for. This sets how far apart the spacing of the lines are. It’s pretty much going to ignore what the shape of the bit is. You’ll have to get a competent cam software to actually get it to calculate the bit in for details.

I’m not talking about tool shape, but tool diameter.

For example. I want to leave the a circle shape relief. Luban tool path is moving the tool center to the object shape path (red). I want the tool path (tool diameter) to stop at the shape path (green).


Interval/density has northing to do with the issue

When I said tool shape, I meant diameter as well. It ignores whatever shape it is, and whatever diameter it is. The only time it actually considers diameter is when you use the “outline” path. At least in my testing, I gave up on Luban for CNC quite early.

Seems Luban v4.x does take the bit diameter into account when computing the path (whereas v3.x didn’t). Heck, v3 didn’t even save user defined tools when quitting the app. Libyan V4 seems to be a worthy update, at least for the CNC portion.

I’ve had the snapmaker for just over a year and this is the first time I’ve used the CNC module. I must say I’m very happy with it. I was very disappointed that the laser couldn’t cut clear acrylic. But the CNC was able to do the job that the laser couldn’t.

I’m trying to cut 2D acrylic using the 1.5mm flat-end bit. (Luban 4.3.2). Doing something much like your project above: a shape with internal holes. I’m finding that the “outline” path is running the bit inside the path, making the piece 3mm narrower than I want it to be. “On the path” makes it 1.5mm narrower. Is there any way other than fudging the path size to get Luban to carve outside the outline instead of inside?

Sadly no. I’m still dumbfounded that Luban only supports Outside and On Path, and no Inside for CNC. I pretty much exclusively use Illustrator to create my own paths for CNC.