How to make a part thinner

ali_e280

Hi,

I created this part by using the boolean subtraction operation.  This part, Lid, was the target and a different part was used as the tool.  The fitment is slightly too tight and I need to make the marked extrusion slightly thinner.  I don't know the best way to do this so I created two offset sketches and tried to use the extrude tool to shave the part.  The extrusion works, but 2 additional parts are created regardless of whether "Merge with all" is selected.

1. Is there an elegant way to slightly shave parts?

2. Why does the extrusion remove create 2 additional parts?

eric_pesty

GWS50

Try the Move Face tool




If you can share your document someone can take a look

ali_e280

Thank you. I will have to play with the Move Face tool.  I don't think it was covered in the basic video tutorial.

Do you know why the extrusion is creating multiple copies of the part?

GWS50

If you could share your document I could take a look

ali_e280

https://cad.onshape.com/documents/b154958933cd20c2cd757983/w/70ce4b0e2189d88e1934ed38/e/375c9a3a22fbcd6abcda1abc

It's the Lid that has the problem.

eric_pesty

You are cutting right through the lid so it's creating disconnected parts. Not sure what you are trying to do / expected to happen with that cut...

If you want that part to be narrower you should just edit sketch3 and make it narrower... Or just use the "move face" as @GWS50 suggested (or add a clearance to your boolean)

ali_e280

eric_pesty said:

You are cutting right through the lid so it's creating disconnected parts. Not sure what you are trying to do / expected to happen with that cut...

If you want that part to be narrower you should just edit sketch3 and make it narrower... Or just use the "move face" as @GWS50 suggested (or add a clearance to your boolean)

I had selected up to next as the extrusion limit so I expected the cut to stop when it reaches the perpendicular surface.  I think I know what I did wrong.  I should have selected up to face, not up to next.

Editing sketch 3 wouldn't work because the Boolean operation would just adjust automatically.  You mentioned adding a clearance to the boolean, but how?  That would be the perfect way to make the target cut slightly larger/smaller than the tool.  I only see an Offset option in the Boolean tool.  Is there a way to add a clearance value to the Boolean tool?

eric_pesty

nick_papageorge_dayjob

Are you 3D printing this? If so, it's usually a good idea to incorporate a lead-in angle for a lid to a bottom. Also, I'd personally get rid of the full tongue and groove, and make it a half-lap. Below is a design common in injection molded boxes.

Here is the CAD if you want to copy the modeling technique:
https://cad.onshape.com/documents/1cb6823e7f9cd5a4abab5faa/v/b071110563b323ab063b8511/e/cadad55b3e2062df53f03c46

ali_e280

eric_pesty said:

Thank you.  I think this is exactly what I was looking for.  Now I just have to play around with the faces to only offset the sides I want.