Too many passes, Makercam issue?

Software
1

Hi,

I have a scenario when I’m in Makercam when I create a pocket and I set the step-down to .125 and the target depth to .3. I would assume that this would be two pass-overs, right? However, after 4,6,8 hours and multiple pass-overs, I’m forced to terminate the process because the cut is too deep and/or the amount of time is ridiculous.

Oddly, I don’t have this issue with profile cuts. .125 stepdown on 3/4" wood is six passes.

Any ideas what’s happening? Things I should try differently?

Thanks in advance.

Tim

2

Tim,

Can you provide the SVG or NC file?
Have you looked at the resulting NC file in a simulator, such as https://ncviewer.com/?

If you are using a step down value of 0.125, then a target depth of 0.3 will require 3 passes, one each at 0.125, 0.25 and 0.3.

Peter.

3

Peter,

Thank you for the response. I’ve uploaded 4 files:

http://hjellum.com/Bristol.nc
http://hjellum.com/Bristol.svg
http://hjellum.com/Aurland.nc
http://hjellum.com/Aurland.svg

As mentioned, the issue is with pockets. I’m somewhat coding savvy so I will review it myself but I appreciate your time and assistance. I’m positive the issue is user related :slight_smile:

Thanks!!

4

Tim,

The first thing I see when I look at Aurland.nc is that it makes 15 passes on the pocket, stepping down 0.05" to 0.75".

The outside profile makes 8 passes, stepping down 0.10" to 0.80".

I concluded all of this by loading the NC file. That showed a lot of movement, so I inspected it in a Text Editor (Visual Studio Code in this case).

I would suggest you get into the habit of putting your NC code through a simulator to check just what it is going to do. If it looks wrong, go back to the drawing board & see if you can find the reason and then try again.

Peter.

5

Peter,

Thanks for opening that file and conducting a biopsy. Looks like human error on my part.
:slight_smile: I have VS Code as well so I will get familiar with the format and also run it through an emulator. I found a good one online.

Thanks for your assistance!

Tim

6

One thing that I run into using HSM CAM for Inventor is that I forget to redefine my stock to be the same as what I am using. The default in the program is to add stock above and below with the thinking that it will be removed during the cutting process, so even if I simulate the cut, it looks like it ends up right because that portion above and below are removed, but when I put the gcode into GC and zero the bit on the surface of the material, it ends up cutting too deep because the gcode accounted for the extra top and bottom stock. (I really need to change that default to have the stock be the extent of the model).

Just something to check, though I don’t know if Makercam does that same thing since it was written specifically for the DIY CNC community.