Glitch with pocket

Post here for help on using FreeCAD's graphical user interface (GUI).
Forum rules
and Helpful information
IMPORTANT: Please click here and read this first, before asking for help

Also, be nice to others! Read the FreeCAD code of conduct!
Post Reply
Kytrix
Posts: 4
Joined: Thu Nov 19, 2020 7:35 pm

Glitch with pocket

Post by Kytrix »

Hello,
I'm quite new as using freecad, and 3D modeling.

I have an issue while doing a pocket (sweep through line) from a datum plane.
I'm using named fields in a spreadsheet.

I get a glitch inside my pipe:
Image
freecad-pocket-issue.png
freecad-pocket-issue.png (144.54 KiB) Viewed 740 times
I opened the Dependency graph, but nothing "appear" to me :D

I didn't see this issue first, but I get a similar problem when trying to made another pocket from bottom.
rhasspy_cylinder_06.FCStd
(47.14 KiB) Downloaded 22 times
I would like to understand what I did wrong.

Regards :)
chrisb
Veteran
Posts: 54201
Joined: Tue Mar 17, 2015 9:14 am

Re: Glitch with pocket

Post by chrisb »

Sketch003 is overconstrained.Besides, why do you use an ellipse whith equal minor and major diameter? Use a circle instead!

The use of SubtractivePipe is unclear: as it lies completely above the tube it will not subtract anything. The additional line is caused by the fact that the path lies outside of the circle. It vanishes if you set Refine=true, which shows that it lies on the top border and nothing was cut away.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Bance
Veteran
Posts: 4255
Joined: Wed Feb 11, 2015 3:00 pm
Location: London

Re: Glitch with pocket

Post by Bance »

I think this is the result that the OP is looking for:-
pipe.png
pipe.png (64.04 KiB) Viewed 719 times
Attachments
rhasspy_cylinder_06Bance.FCStd
(52.75 KiB) Downloaded 14 times
chrisb
Veteran
Posts: 54201
Joined: Tue Mar 17, 2015 9:14 am

Re: Glitch with pocket

Post by chrisb »

But why would he add the final subtractive pipe then if the result was there before?
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Bance
Veteran
Posts: 4255
Joined: Wed Feb 11, 2015 3:00 pm
Location: London

Re: Glitch with pocket

Post by Bance »

It wasn't, he was trying to get a rebate on the angled cut of the pipe using a sweep.

Probably should have tried to use a vertical line to sweep the ellipse.
Kytrix
Posts: 4
Joined: Thu Nov 19, 2020 7:35 pm

Re: Glitch with pocket

Post by Kytrix »

Thanks for your help !!!
So I removed the datum plane and use Bance technique for cuting the pipe.
I kept the ellipse sweep cut (instead of booleans).

I will post the final pieces :)

Regards.
Kytrix
Posts: 4
Joined: Thu Nov 19, 2020 7:35 pm

Re: Glitch with pocket

Post by Kytrix »

Hello, that's me again :D

this time i would like to make a cut pattern(hexagons)
here is the first cut (seems ok)
hexagon.png
hexagon.png (116.59 KiB) Viewed 571 times
but when I use the multiply tool somes glitches appear:
hexagon-multi.png
hexagon-multi.png (251.3 KiB) Viewed 571 times
The "problem" come from the first hole which mus be done with an angle (all angle must be joining the Z axis) instead of being paralel to the Y axis.
I try to add two lines in a sweep cut, but it doesn't work.
I also don't know how to reproduce easyly my hexagon first sketch to apply it on the inside face with width reduction to apply a loft cut (and if it will work at the end ..)
I know i can't sketch directly on my cylinder face ...

how to do that ? :)

Regards.
chrisb
Veteran
Posts: 54201
Joined: Tue Mar 17, 2015 9:14 am

Re: Glitch with pocket

Post by chrisb »

If you place the inner hexagon at exactly half of the distance of the outer hexagon then you can sketch it with exactly half the size and use a subtractive loft.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Kytrix
Posts: 4
Joined: Thu Nov 19, 2020 7:35 pm

Re: Glitch with pocket

Post by Kytrix »

chrisb wrote: Sun Nov 22, 2020 6:33 pm If you place the inner hexagon at exactly half of the distance of the outer hexagon then you can sketch it with exactly half the size and use a subtractive loft.
Thanks for the tip, it works. I had to do 3 times (one for each hole).
I still have an tiny overlapk but it's not an issue at all during printing
2020-11-23_21-39.png
2020-11-23_21-39.png (155.97 KiB) Viewed 512 times
IMG_20201123_214009.jpg
IMG_20201123_214009.jpg (150.06 KiB) Viewed 512 times
I will correct this before the final print ;)
Post Reply