Hello,
Is there any tutorial on DOF and how to not over-constrain an assembly?
With two "square parts" I usually use "Same orientation" + "Point coincident" to remove the 6 DOF without over-constraining...but with more parts or round parts I don't know.
Here is an example: two cylinders with a 2mm hole, two flat bar with two 2mm holes at each end.
The first flat bar is locked
I use "Plane coincident" on the hole edge of the bar and the hole edge of the cylinders -> 5 DOF out, the last one (Rz) doesn't matter
Idem for the second cylinder.
And now the last bar... I can use the same method but it will over-constrain. Shall I constrain the second bar with only one cylinder? Use both? Try to constrain with the first bar? What is good practice, what is the way of reasoning?
Assembly3 - DOF
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- Shalmeneser
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- Joined: Wed Dec 23, 2020 12:04 am
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Re: Assembly3 - DOF
(BTW, Sketch004 is horrific.)
- Attachments
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- CTEX_SHALM.FCStd
- (110.79 KiB) Downloaded 5 times
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- Capture d’écran 2022-07-07 114130.jpg (77.69 KiB) Viewed 354 times
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- Capture d’écran 2022-07-07 114245.jpg (158.28 KiB) Viewed 354 times
Re: Assembly3 - DOF
Shalmeneser:
FBXL5: Thanks, I didn't know about this "Lock Angle" property
More than a solution for this specific topic, I'm more looking for a "Good practices" advice that I can apply generally.
True, but it's not the topic, and it's not really constructive...any hint how to improve this sketch?Sketch004 is horrific
FBXL5: Thanks, I didn't know about this "Lock Angle" property
More than a solution for this specific topic, I'm more looking for a "Good practices" advice that I can apply generally.
- adrianinsaval
- Veteran
- Posts: 5544
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Re: Assembly3 - DOF
I would make just one circle then use a PD multi-transform, make another sketch and re-pad the sections where there shouldn't be holes (center and corners), looking at his tree it seems that's what shalmeneser did too.
- Shalmeneser
- Veteran
- Posts: 9545
- Joined: Wed Dec 23, 2020 12:04 am
- Location: Fr
Re: Assembly3 - DOF
The file is in my 1st message above the image.