Why is my Extrude - Remove failing?

sean_eberhart476

I have a sheet metal part that I am unable to extrude-remove material from the flanges.  I think OnShape is trying to tell me what is wrong but I don't get it.  I have extrude-removed holes and fillets on flanges in other drawings with success but using the same process here is giving me an error this time.

Work Flow:
Sketch footprint on front plane.
Extrude sketch to make 3D part.
Convert to Sheet Metal Part.
Create plane on flange and sketch area to be removed.
Extrude remove  <-- Fails but shows a red/orange line like when a collision is detected.
https://cad.onshape.com/documents/e628773a7d7cc074e2a843e7/w/8da972ab8b79fd289a411b2b/e/370551b32a153bb4f24c9476


Any suggestions?  Thanks for whatever help you can offer.

Cheers

Jason_S

Your extrude is touching the rip joint that exists, as the tool tip explains. Right now we do not support that.


To get around that, I excluded some faces from the sheet metal feature, did the cut, then added flanges to make up for the faces. We are looking to improve sheet metal tools in the future to support the workflow you described.

https://cad.onshape.com/documents/58d979644ff5680f6d416d8d/w/7bf59394460a48a647f91fed/e/098bf63debb947be388ca71b



Thanks and if there are any other questions, please do not hesitate to ask!

Jason

Brooke_Bohlken

Hey @sean_eberhart476,

I would suggest extending the sketch past the edges of your sheetmetal part. Doing this should let you extrude remove- just make sure you extrude a distance equal to the thickness of your sheetmetal if you want to remove material from that side only. You can use a global variable for that if you'd like.

Take a look at sketch 2 to see what I meant: https://cad.onshape.com/documents/3a881554e7e4c51393a4f156/w/ff94f03e639ee3d8ca5ed90d/e/c0ec76f4aa68d315b8fc3ba3

Jason_S

Your extrude is touching the rip joint that exists, as the tool tip explains. Right now we do not support that.


To get around that, I excluded some faces from the sheet metal feature, did the cut, then added flanges to make up for the faces. We are looking to improve sheet metal tools in the future to support the workflow you described.

https://cad.onshape.com/documents/58d979644ff5680f6d416d8d/w/7bf59394460a48a647f91fed/e/098bf63debb947be388ca71b



Thanks and if there are any other questions, please do not hesitate to ask!

Jason

Brooke_Bohlken

Hey @sean_eberhart476,

I would suggest extending the sketch past the edges of your sheetmetal part. Doing this should let you extrude remove- just make sure you extrude a distance equal to the thickness of your sheetmetal if you want to remove material from that side only. You can use a global variable for that if you'd like.

Take a look at sketch 2 to see what I meant: https://cad.onshape.com/documents/3a881554e7e4c51393a4f156/w/ff94f03e639ee3d8ca5ed90d/e/c0ec76f4aa68d315b8fc3ba3

sean_eberhart476

@Jason_S & @Brooke_Bohlken
Thanks for the workarounds.  I'm really looking forward to the next evolution of sheet metal tools.  Thanks again to both of you!

andrew_klug

Any plans to allow negative extrude at a joint? The sheet metal tools are amazing but this seems to be the one weak spot that keeps hanging me up.

NeilCooke

@andrew_klug can you share an example?

andrew_klug

NeilCooke said:

@andrew_klug can you share an example?

Sure the attached picture showed a negative extrusion through a sheet metal part (grey). Then I extruded another part (blue) through it so the two will lock together. When I try and negative extrude a rectangle or create a tab at the but joint line (yellow) it wont work. Move 1 mm away and no problem. This part is just 1 example. Same issue initially described in this thread.