Extrude part around another part

baumar

I'm trying to extrude a part from a sketch, which would be easy if there wasn't another part already there and the new part should be around that part. 

To illustrate I made an example with a cube and another piece that should 'wrap' the cube.
I managed to do this with couple of steps like create a part to the left and the right (because I cannot select the surface under the cube) and then connect them with other extrudes.
https://cad.onshape.com/documents/54fef70b9a33760c3c41dfe8/w/a9228853478954cd7c94a254/e/052d3a11f4c934a8176c71e1

I made another smaller part wrapping the cube to make the problem more clear. I was hoping to get a way to select the whole rectangle and extrude and experimented with intersect and boolean subtract but that didn't work. 

Instead of doing all these many detail steps would there be a solution to do that in 1or 2 actions (extrude and ?)


Another problem I had with such a design: if there is a part on the top plane and the new plane, I could not access the elements of the sketch. Is there a way to position the centre within a set of surrounding parts?

baumar

Note: I did use the section view, but when selecting either of the planes the other was still hiding elements of the sketch that I didn't manage to select through the part

Prachi

Not sure what your purpose is to build one part in another but....
When I need to select from the same sketch which is covered by part one and I may use the original part face for as the working plane then "hide" the original part from the part list in the middle of the extrude for part 2. The ability to hide and show parts or sketches pretty much any time you like is quite nice.

Jason_S

@baumar, 
Are you looking for something like this (this is a section view)? I removed the other extrudes to make the issue clear.
https://cad.onshape.com/documents/58d980bf3d69580f7f1231a2/w/74eebcba7c03961766131697/e/36654598d1ede1d73fbd8638



1) I created a sketch on the blue part's face and used the gray parts faces in the sketch
2) Closed the box and extruded it from the blue part only
3) Did a Boolean-Subtract to remove the material from the grey part and checked the "Keep tools" box to keep the blue part

If you need any help, please do not hesitate to post here, contact support, or if you would like, we can get you in a training course. Also see our 100+ tutorial videos here: https://www.onshape.com/videos/topic/tutorials

Best!

Jason

baumar

@Glen Sorry if I was not clear. I want to build the other part around the other not in the other. Eg to fasten the cube on the plane... I tried what you said, but then the 2 parts were both solid, I wanted the new part going around the other one (as new one)

@Jason Thanks for the hint. I have to learn more what 'tools' are, I didn't get that yet. 
I see you corrected a detail I had overseen - that the piece was not hollow. 

I guess my idea or wish was just too freaky. When you look at the state after extrude 1 of the cube, you see the ground plan of the new part. I was wondering if there was an easy way to select the whole orthogonal rectangle for the "wrapper" - by hiding the cube as Glen suggested - and extrude the wrapper. When I did this, the 'wrapper' was solid and I did not manage to subtract. I guess I have to practice with that a little bit.

Concerning training: What training do you offer apart from the essential training?

Jason_S

I'll have one of our guys who knows more about training get in contact with you. Thanks!