Milling an area with open edges

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MPC
Posts: 14
Joined: Tue Mar 02, 2021 10:41 am

Milling an area with open edges

Postby MPC » Wed Jun 09, 2021 2:53 pm

Hi,

Sorry I posted this on the general freecad help but its more a PATH related.

Any ideas how to mill out an open edge area?

I have tried several different attempts but I have completely failed. Any suggestions?

Kind Regards,

MPC
Screenshot from 2021-06-09 15-40-50.png
Screenshot from 2021-06-09 15-40-50.png (234.94 KiB) Viewed 612 times
chrisb
Posts: 35188
Joined: Tue Mar 17, 2015 9:14 am

Re: Milling an area with open edges

Postby chrisb » Wed Jun 09, 2021 3:18 pm

I removed the duplicate from the help forum.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Paula
Posts: 32
Joined: Tue Jan 26, 2021 10:06 pm

Re: Milling an area with open edges

Postby Paula » Wed Jun 09, 2021 3:30 pm

I'm not a professional machinist so I might be wrong but I think you're supposed to mill the face before performing the pocketing.
chrisb
Posts: 35188
Joined: Tue Mar 17, 2015 9:14 am

Re: Milling an area with open edges

Postby chrisb » Wed Jun 09, 2021 3:50 pm

MPC wrote: Wed Jun 09, 2021 2:53 pm Any ideas how to mill out an open edge area?
Use a pocket and check the appropriate edge in the Extensions tab.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Russ4262
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Joined: Sat Jun 30, 2018 3:22 pm

Re: Milling an area with open edges

Postby Russ4262 » Wed Jun 09, 2021 5:24 pm

MPC wrote: Wed Jun 09, 2021 2:53 pm ... Any ideas how to mill out an open edge area? ...
As ChrisB suggested, and MLampert encourages, use the Extensions feature of the regular Pocket operation to extend edges, expanding access to such regions. See the last image.

EDIT: A second option is to select both the upper open edge face and the inner lower and clear them together at the upper face depth, then do a second clearing op with only the inner lower selected. See second and first image.

BR,
Russell

OS: Windows 10 Version 2009
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24276 (Git)
Build type: Release
Branch: releases/FreeCAD-0-19
Hash: a88db11e0a908f6e38f92bfc5187b13ebe470438
Python version: 3.8.6+
Qt version: 5.15.1
Coin version: 4.0.1
OCC version: 7.5.0
Locale: English/United States (en_US)
Attachments
Upper open face and lower inner face cleared together will grant access to that open edge (ledge, shelf)
Upper open face and lower inner face cleared together will grant access to that open edge (ledge, shelf)
Snip macro screenshot-06488a.png (216.52 KiB) Viewed 521 times
Alternative strategy, selecting upper and lower faces and clearing at upper height, then create clearing op for lower only.
Alternative strategy, selecting upper and lower faces and clearing at upper height, then create clearing op for lower only.
Snip macro screenshot-dda7d3.png (200.53 KiB) Viewed 523 times
plate_replica_1.FCStd
Pseudo replica source file
(231.76 KiB) Downloaded 5 times
Extension feature usage, with Default Length increased slightly
Extension feature usage, with Default Length increased slightly
Snip macro screenshot-80f7ec.png (217.83 KiB) Viewed 541 times
MPC
Posts: 14
Joined: Tue Mar 02, 2021 10:41 am

Re: Milling an area with open edges

Postby MPC » Thu Jun 10, 2021 12:50 pm

Hi,

Thanks for the suggestions.

Unfortunately it still fails.
Below is the pocket with the wire extension checked and Extend corner checked. You can see the cutter is driven into the part.

Extended Corners.png
Extended Corners.png (12.01 KiB) Viewed 445 times

Below is the Extend Corners unchecked but all edges checked

All edges selected.png
All edges selected.png (8.22 KiB) Viewed 445 times

Below is the Extended Corners unchecked but only partial edges selected.

Partial edges selected.png
Partial edges selected.png (11.13 KiB) Viewed 445 times

This is from a different body where I used Mill Face with Boundary Shape set to 'Face Region' and this successfully extended beyond the open edges. This does not work with the fillet part though.

MillFace Different Part.png
MillFace Different Part.png (74.83 KiB) Viewed 445 times


I get this error message when I try Mill Face with Boundary Shape set to 'Face Region' on the Fillets.

Error Message.png
Error Message.png (120 KiB) Viewed 445 times


Could it be that the fillets were done in Part Design and not done as part of the sketch?


Any more thoughts?

Kind Regards,

MPC
chrisb
Posts: 35188
Joined: Tue Mar 17, 2015 9:14 am

Re: Milling an area with open edges

Postby chrisb » Thu Jun 10, 2021 1:59 pm

MPC wrote: Thu Jun 10, 2021 12:50 pm Could it be that the fillets were done in Part Design and not done as part of the sketch?
I don't think that Path workbench cares about how an object was built, but running CheckGeometry with BOPCheck enabled is probably a good idea.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
MPC
Posts: 14
Joined: Tue Mar 02, 2021 10:41 am

Re: Milling an area with open edges

Postby MPC » Thu Jun 10, 2021 2:21 pm

Thanks chrisb,

I tried your suggestion but I got no errors.

Check Geometry.png
Check Geometry.png (104.27 KiB) Viewed 409 times


OS: Ubuntu 20.04.2 LTS (ubuntu:GNOME/ubuntu)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24291 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 0.19.2)
Hash: 7b5e18a0759de778b74d3a5c17eba9cb815035ac
Python version: 3.8.8
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.4.0
Locale: English/United Kingdom (en_GB)
chrisb
Posts: 35188
Joined: Tue Mar 17, 2015 9:14 am

Re: Milling an area with open edges

Postby chrisb » Thu Jun 10, 2021 5:18 pm

Preliminary remark: The PartDesign features have a Refine property which make the separate object obsolete.

Concerning the rounded corner: In the attached example I used a profile of the to face and changed the depth appropriately. Then I added a boundary dressup. It's not exactly what you want, because it creates additional paths, but it does at least do the job in an automated way.
SnipScreenshot-b44d08.png
SnipScreenshot-b44d08.png (6.03 KiB) Viewed 382 times
Attachments
plate_replica_cb.FCStd
(159.05 KiB) Downloaded 3 times
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
MPC
Posts: 14
Joined: Tue Mar 02, 2021 10:41 am

Re: Milling an area with open edges

Postby MPC » Fri Jun 11, 2021 8:57 am

Thanks chrisb,

That's a very useful suggestion.

I did a bit more experimenting and found something very interesting.

I built a cube with a pocket and fillet edges.

1. I did the fillet using sketch --- Mill face worked and extended correctly

2. I did the fillet using part design. --- Mill Face failed with error --> 19Standard_OutOfRange NCollection_Sequence::Value19Standard_OutOfRange NCollection_Sequence::ValueSomething unexpected happened. Check project and tool config.

Below is the working mill face

MillFace using sketch for fillet.png
MillFace using sketch for fillet.png (81.77 KiB) Viewed 296 times

Is this worth raising as a bug?

Kind Regards,

MPC
Attachments
Test_using_sketch_fillet.FCStd
(78.88 KiB) Downloaded 10 times