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Should complicated geometry for a single profile be sketched in multiple sketches
james_aguilar160
Member Posts: 57 ✭✭
I'm working on 3d printing an escapement. I've got a working prototype, but there's something wrong with the interface between the fork and the roller, so I'm redoing that part to try to get to the bottom of it.
I'm using two books as a resource. In both books, they have a tendency to sketch different parts of the lever in different sketches, because it's pretty complicated (example, book url). In my first cut at this project, I sketched the faces of the pallet "jewels" separately, but then I combined the rest of the fork into a single sketch.
The second time around, I was contemplating if I should also separate out the fork, where it interfaces with the roller of the balance wheel. It is a pretty complicated bit of sketching, by my lights. Another reason to separate the sketch is that this portion of the interface is most easily sketched when the roller jewel and the pallet fork are in their most extreme positions, whereas the rest of the pallet fork is most easily sketched when it's in its neutral position.
Here's the sketch itself:
https://cad.onshape.com/documents/0e61cd74786fef010d268f4a/w/f5ae16a78db1752256e3e7a7/e/1c370f8d7102c1b1b17dd55d?renderMode=0&rightPanel=variableTablePanel&uiState=683914adc8836b2a4c58ff3c
To give you a sense of what I'm talking about when I mention the complexity of the sketch, here's a screenshot:
My plan at the moment is to take this profile as construction geometry in the next sketch, then rotate it into place and finish sketching the body of the pallet fork. I would appreciate the advice of any experts on whether this is the best way to manage this complexity.
Comments
I tend to do sketch/ 3D, sketch 3D. I try to do one part at a time. Then your sketches can build upon existing 3D geometry. If you're 3D printing you might run into tollerence issues. For separate parts you'll need a gap of around 0.4mm, give or take, depending on your printer.
You very much want to do separate sketches on top of each other, each sketch for a specific thing and as simple as possible. Downstream sketches reference upstream sketches. You can freely apply constraints between entities in one sketch and another.
I posted this a few days ago but it took a while for it to get through moderation. In the end I did separate the different parts of this one solid into separate sketches. There is one sketch for the pallet profile, one sketch for the head profile, and then a sketch that brings those two together and completes the rest of the pallet fork geometry. I also made a master elevation sketch that shows how all the parts go together, and referenced that sketch when extruding all the parts. I found moving everything into separate part studios improved rendering time quite a bit. It was never that bad but it was starting to slow down a touch toward the end.
If I were doing it again, I would take an even more top-down approach. But this worked out okay and the assembly seems to go together properly.
remember you can also give different colors to the sketches which may help in readability of the combined sketches