[SOLVED] Some holes disappear in 2-body fusion

[ulidtko]

Greetings! New user here.

I'm a long-time Open Source enthusiast, and just recently started learning FreeCAD. Fascinating project I must say! Having modeled a few solid things in the past using the wrong tool for that (cough-cough Blender ) I'm shocked how accessible, easy to approach and powerful FCD is. TechDraw workbench deserves special mention (the Drawing workbench should be just removed, I was disappointed and confused by it for quite a while).

You guys, the core team, everyone who contributes, reviews PRs, fixes CI, maintains the wiki, helps on the forums & IRC, etc — are carrying gravely important mission, that's not to be understated.

I do really mean that; but let me move on to something interesting (I hope).

This model I made has two bodies: body base and pulley teeth. The former has holes in it. Hmmm I shouldn't spend words on it, here's how it looks:

Screenshot from 2020-10-27 01-17-22.png (242.05 KiB) Viewed 839 times

The problem is, for a final tech drawing I need these merged/fused (and refined)
... but whichever approach I try, the small holes on the bottom near the teeth disappear:

Screenshot from 2020-10-27 01-26-05.png (174.43 KiB) Viewed 839 times

I tried all of:

• Part Union
• OpenSCAD Union
• PartDesign Boolean

... all give the same result: the bottom holes disappear.

I was careful to not place the holes touching any edge or wall, there's spacing. The diameters of teeth & base body are explicitly set at 90.5; adding spacing between them does not help:

photo_2020-10-27_01-48-51.jpg (34.24 KiB) Viewed 839 times

The model was made in v0.18 (r16158) and maybe there's something funny in the document history — as I was fumbling around a lot and had to make several reattachments, recomputes and error fixes.

I tried loading it in v0.19 (r22846-Linux-Conda_glibc2.12-x86_64.AppImage) but that didn't help anything; the holes still disappear with any of the fusion methods.

The FCstd file somehow doesn't fit the forum upload limit; check here https://drive.google.com/file/d/1gdzxJb ... sp=sharing

Can anybody else confirm the behavior? If so, I should probably report this at the Mantis bug tracker.

More importantly for me... are there workarounds I don't see? Perhaps it's possible to erase a circle in TechDraw? I don't really need the parts fused, if not for trying to obtain neat tidy drawing.

[chrisb]

Moved to help forum.

I have some difficulties to download, but I would guess it's a coplanar issue.

[jmaustpc]

(the Drawing workbench should be just removed, I was disappointed and confused by it for quite a while).

No it should not, it is deprecated but not removed because if it was removed then that would remove compatibility with old FreeCAD files that may contain a "Drawing" object.

[chrisb]

It was something different: You have changed the tip, so the body didn't reveal it's final state to the outside world. Set it in body base to the final fillet and all is well.

[ulidtko]

It was something different: You have changed the tip, so the body didn't reveal it's final state to the outside world. Set it in body base to the final fillet and all is well.

Uhhh... no?

Screenshot from 2020-10-28 03-10-42.png (114.43 KiB) Viewed 822 times

[ulidtko]

No it should not, it is deprecated but not removed because if it was removed then that would remove compatibility with old FreeCAD files that may contain a "Drawing" object.

Okay, sure, I meant "remove with deprecation"

[ulidtko]

Uhhh... no?

Screenshot from 2020-10-28 03-10-42.png

Well, here I forgot to turn off teeth visibility, so there's a line.

This is without the line. Body tip at the last fillet; no holes.

Screenshot from 2020-10-28 03-16-51.png (138.9 KiB) Viewed 815 times

[chrisb]

Tip is not at Fillet001, it is - as far as I can see from the image - still at "bearing retainer thread".
See https://wiki.freecadweb.org/PartDesign_Body#Tip

[Bance]

still at "bearing retainer thread".

+1

[ulidtko]

Tip is not at Fillet001, it is - as far as I can see from the image - still at "bearing retainer thread".

OMG that little mark? Sorry, I didn't see it... Missed it completely. How to reset?