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Very Simple Boolean Fails
janis_holman
Member Posts: 4 ✭
Hello,
I was working on a model that involved using booleans to create tab-and-slot joints for cnc machining. I wanted to offset certain faces to allow a clearance for fitment, but I didn't want to individually select a gazillion faces, so I was looking for a way to do an offset boolean and then use a linear pattern to create multiple instances of that geometry.
This approach worked well to generate the parts that I needed, but then I tried to boolean my whole model together to create a simplified "block" that I could use as a derived part in other part studios. This doesn't work.
The geometry is very simple, there is plenty of contact between the faces, no weird shapes ... but it doesn't work. Please let me know what you think. This is a url for the file:
https://cad.onshape.com/documents/e9201d60734dc348f6561414/w/54569915ca7f991d84e26090/e/22be82161c16fff7da9b4f95
Thanks you !
I was working on a model that involved using booleans to create tab-and-slot joints for cnc machining. I wanted to offset certain faces to allow a clearance for fitment, but I didn't want to individually select a gazillion faces, so I was looking for a way to do an offset boolean and then use a linear pattern to create multiple instances of that geometry.
This approach worked well to generate the parts that I needed, but then I tried to boolean my whole model together to create a simplified "block" that I could use as a derived part in other part studios. This doesn't work.
The geometry is very simple, there is plenty of contact between the faces, no weird shapes ... but it doesn't work. Please let me know what you think. This is a url for the file:
https://cad.onshape.com/documents/e9201d60734dc348f6561414/w/54569915ca7f991d84e26090/e/22be82161c16fff7da9b4f95
Thanks you !
0
Answers
I used to get frustrated with that behavior. But now it seems to make sense that this would be very hard to handle. At that point, that corner is kinda undefined. Is there an infinitely small gap? Or is there an infinitely small overlap? Are you making two interior, concave corners or two exterior, convex corners? Or maybe all four? But it's all one line. Feels a lot like wanting to be able to put 1/∞ as a dimension. Is an infinitely small volume super useful for developing accurate mathematical models with calculus? Yes definitely! Can you display one in a 3D model? Not easily/accurately..
You can also think about it from a manufacturing stand point. If you were gonna mill that out of a block of aluminum, you'd either have a little bit of material left there, or you wouldn't! I guess, if you did some super fancy nanoscale manufacturing, you could get one string of atoms along that corner, but that's still overlapping my an atom
I guess that is in fact happening at these highlighted locations. I thought it would be able to boolean everywhere else, but it makes sense to me now why that isn't possible.
@NeilCooke I tried using a composite part instead of a boolean to simplify part studios before referencing them elsewhere and that is a much better approach. Thank you