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Boolean operation results in non-manifold body
Answers
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Hey @Nimaye_Garodia,
This gives you an error because the result is non-manifold geometry (you can search the forum if you want to understand better what that is).
You don't need to do a boolean operation to combine this, you also don't need to extrude 3 bodies. You can just use one extrude feature and select all the sketch entities that you wanted to create a single combined body.
Hope this helps.
Cheers
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There is a problem with your sketch where you can see below. Looks like there are 2 arcs at this place with different radiuses and it creates an empty spaces between Part 1 and Part 2 thus creating a new part. I found it when I saw your Extrude2 is in Add mode but creates a new part.

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I had the same problem and what I found is this happens when two parts you're using to extrude with overlap, this error comes up. If you want two put two circles in a square, the circles can't overlap or at least it can't on my Onshape.
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Good day !
seems that i have an error about the boolean non-manifold but after reading all the tips Istill don't get why
if anyone can shed some light on this please ?
I see no curves or parts not touching , the reason I need those allparts together is to create an assembly so I can make sure all parts are well aligned so i can 3D print them , in the mean time i will continue searching what am I doing wrong and or don't understand ,
I've been Cading for 3 years on a here and there basis ! so yes still steep mountain for me to get the hang of it !
regards
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have you posted your own thread with a link to your project oroject and what you seem to have trouble with? It's tuff to point you in a direction if not. Non manifolds are hard to textually explain.
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Sorry my bad
i will try to explain a bit here :
1- in the bar where we have our studio & assembly , into the one call MAIN CHUTE I was regrouping all the parts so I can create a ONE part only to create and work on an assembly .
2- on that studio MAIN CHUTE all parts are grouped but this is where i have the orror about non-manifold due to the fact that 2 parts seems to create the issue ( part left rib & part right rib ) if i remove the 2 parts then the boolean is created properly , but I would really like to have them all .
3- the boolean part is called part main chute all in one ( when it work )
4- it is used in assembly called "chute eye"
5- all the rest works pretty fine but that boolean thing is a good bone in the crusher !
6- I still try to browse videos & tutorials but no luck .
i tried all i could to figure out if i had a space somewhere on any other thing but can't find it , I read all i can about non-manifold and no luck .
here is a new link :
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A non manifold body essentially means it has no clear inside or outside. You can't have a physical object that has no inside or outside.
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There is no non manifold errors in your model when I opened it
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No Boolean is needed when no voids are left in play. You have drawn 2 unnecessary lines that are leaving a void and are making a non manifold condition during the extrude. and cannot Boolean together.
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thx for the help very appreciated!
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to simplify: this error often comes up when parts are just touching (sometime tangentially).
The underlying model will have difficulty deciding what's in and out after uniting. This leads to errors as the models become more complicated and underlying CAD tolerances stack up. so what will work in simple geometry, may not with more complicated models.
so make sure there's a gap or a decent interference before uniting… A small 0.1mm move face feature before a unite is not a pretty way, but it works. .
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Mine says "boolean operation would result in non-manifold bodies" and i don't know why but it is a very complicated shape here is the link https://cad.onshape.com/documents/75d276c10aba076773862340/w/b5e5b3d92d3e766a6e05382f/e/fcd8ca061863106a53342284?renderMode=0&uiState=6791503de665d65be2f460ff
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says no permission to view
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How do i give permission?
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At the end of this video when you go into the sharing link you can turn on/off different aspects of permissions
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alright it should be working now
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I can view it now but not edit/copy. Says its view only so I cannot inspect it… I would need to make a copy to examine the non-manifold issue. looks like your might be on and EDU license so potentially you instructor has limited sharing ability somehow. If so maybe you can post images of the sketch and extrusion creating the issue
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So i am trying to remove a section and i dont know why it wont let me but it does highlight this section
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Because you would be creating zero thickness edges where the inside would be touching the outside of the model. Parasolid (and the real world of actual physical parts) don't support that. Some CAD systems will let you model things like that, not Parasolid based ones.
See also:
https://forum.onshape.com/discussion/20585/better-error-handling-and-training-around-zero-thickness-parasolid-limitsSimon Gatrall | Product Development, Engineering, Design, Onshape | Ex- IDEO, PCH, Unagi, Carbon | LinkedIn
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The issue is what it says on the tin: you'd get nonmanifold edges, one of which is highlighted in bright red. You'd have to grow or shrink the profile to extrude.
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while the issue is non manifold. Saying non manifold is like a foreign language to many users. Saying it would create zero thickness geometry would help many understand the limitation slightly better. Voted for the improvement idea.
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