Engrave a sketch?

Here's the place for discussion related to CAM/CNC and the development of the Path module.
falviani
Posts: 63
Joined: Tue May 07, 2019 8:49 pm

Engrave a sketch?

Postby falviani » Tue Dec 10, 2019 4:55 pm

Hi,

My setup:
OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.18842 (Git)
Build type: Release
Branch: master
Hash: 2fa9369d4203f33c62afddfbe190bb4e089d1840
Python version: 3.6.8
Qt version: 5.12.1
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/United States (en_US)

I wish to be able to create a simple grid I can use for alignment when setting up my wasteboard. All I need is to draw a grid in the sketch workbench, but I can't figure out how to create a toolpath so I can carve it. Trying to create a pocket so there are edges to work in an edge profile operation with just yields "Failed to create a face from wire in sketch". I can't use the engrave operation because there's no geometry to use. Suggestions are welcome (I seem to be a perpetual noobie..).

The file is attached, without the failed pocket step.

Frank
Attachments
GridTest.FCStd
(23.02 KiB) Downloaded 8 times
etrombly
Posts: 5
Joined: Thu Dec 05, 2019 6:50 pm

Re: Engrave a sketch?

Postby etrombly » Tue Dec 10, 2019 6:38 pm

You need to select the grid sketch as the model for the path job. Then you can use the engrave operation. You don't need to pad the sketch or anything.
Attachments
grid.FCStd
(383.42 KiB) Downloaded 7 times
falviani
Posts: 63
Joined: Tue May 07, 2019 8:49 pm

Re: Engrave a sketch?

Postby falviani » Tue Dec 10, 2019 8:09 pm

Sorry - I can't select the grid sketch. Only solids are available. If I edit the job to remove the solid and select the model, it still doesn't work. I can select grid lines in the base geometry of the engrave operation, but can't add them.

Again, thanks for the suggestion.
Frank
chrisb
Posts: 21463
Joined: Tue Mar 17, 2015 9:14 am

Re: Engrave a sketch?

Postby chrisb » Tue Dec 10, 2019 8:43 pm

You have to move the sketch out of the body.
RatonLaveur
Posts: 437
Joined: Wed Mar 27, 2019 10:45 am

Re: Engrave a sketch?

Postby RatonLaveur » Tue Dec 10, 2019 9:23 pm

Alternatively the PathFromShape tool is a high speed low drag option, with a strong caveat that it does wonky things with the reference point. Not sure how to circumvent that.

At least it transforms your sketch verbatim into a path.
falviani
Posts: 63
Joined: Tue May 07, 2019 8:49 pm

Re: Engrave a sketch?

Postby falviani » Tue Dec 10, 2019 9:58 pm

"You have to move the sketch out of the body."

I figured out how to do that - I need to detach it from the face, so there are no solids to select when creating the job (with the sketch selected), just the sketch. After detaching the sketch it still appears to be part of the body, however. Thanks!

However, when I go to create the engrave operation, I can only add 1 line to the base geometry. The gcode shows that only the single line is carved. Is that a known bug?

-Frank
chrisb
Posts: 21463
Joined: Tue Mar 17, 2015 9:14 am

Re: Engrave a sketch?

Postby chrisb » Tue Dec 10, 2019 10:12 pm

You can drag the sketch out of the body and drop it on the filename.

The job creates all the g-codes for the grid.
Attachments
GridTest_cb.FCStd
(11.12 KiB) Downloaded 13 times
falviani
Posts: 63
Joined: Tue May 07, 2019 8:49 pm

Re: Engrave a sketch?

Postby falviani » Tue Dec 10, 2019 10:39 pm

Interesting. I created a new file containing the body, sketch and job. Created the job with just the sketch and didn't select anything when I created the engrave operation. While the simulation was quite slow, the gcode seemed sensible for the most part. I would not have thought of that approach at all.

Again, thanks,
Frank