(Solved) Profile: How to get rid of the last pass?

Here's the place for discussion related to CAM/CNC and the development of the Path module.
Forum rules
Be nice to others! Respect the FreeCAD code of conduct!
Post Reply
User avatar
pathfinder
Posts: 315
Joined: Mon Oct 04, 2021 10:27 am

(Solved) Profile: How to get rid of the last pass?

Post by pathfinder »

Hello,

when I cut a profile, there's always a last pass with zero additional depth, so the machine does a pass that doesn't really cut anything and is unnecessary for my current work. I guess it's a clean-up pass? This happens at different thicknesses of material. How do I disable this?

TIA
Last edited by pathfinder on Sun Oct 17, 2021 8:32 pm, edited 1 time in total.
chrisb
Veteran
Posts: 53930
Joined: Tue Mar 17, 2015 9:14 am

Re: Profile: How to get rid of the last pass?

Post by chrisb »

No problem here. Add your FreeCAD info and a simple file showing the issue.

OS: macOS 10.16
Word size of FreeCAD: 64-bit
Version: 0.20.25943 (Git)
Build type: Release
Branch: master
Hash: a65464b722a846bd2999aa2fecdff1132b15b297
Python version: 3.9.7
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.2
Locale: C/Default (C)
Attachments
profile.FCStd
(11.98 KiB) Downloaded 27 times
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
User avatar
pathfinder
Posts: 315
Joined: Mon Oct 04, 2021 10:27 am

Re: Profile: How to get rid of the last pass?

Post by pathfinder »

Sure thing:

OS: Debian GNU/Linux 9 (stretch) (openbox)
Word size of FreeCAD: 64-bit
Version: 0.20.25943 (Git) AppImage
Build type: Release
Branch: master
Hash: a65464b722a846bd2999aa2fecdff1132b15b297
Python version: 3.9.7
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.2
Locale: English/United States (en_US)
Attachments
triangles.FCStd
(142.93 KiB) Downloaded 32 times
GeneFC
Veteran
Posts: 5373
Joined: Sat Mar 19, 2016 3:36 pm
Location: Punta Gorda, FL

Re: Profile: How to get rid of the last pass?

Post by GeneFC »

It looks like there might be a rounding or precision problem. The stepdown is set to exactly one-half of the total depth, but it seems there is some slight difference in calculation.

One pass is at a depth of z=-8.000000 mm and the last pass is at z=-8.000458 mm.

I have displayed 6 digits. You may not see this if you have less digits.

The solution is to slightly adjust the stepdown so that only two passes are needed.

(There is also some sort of problem with an extra Dressup Tag outside the normal hierarchy. Probably not an issue for the extra pass, but something is wrong.)

Gene
User avatar
pathfinder
Posts: 315
Joined: Mon Oct 04, 2021 10:27 am

Re: Profile: How to get rid of the last pass?

Post by pathfinder »

Thanks, that's probably it, I'll look into that. I only have two digits displayed.

There's a lot of stuff wrong with that one. I think one of the triangles isn't even a solid or something. It cut fine in the end, though.
Post Reply