Circular pattern of remove extrustion

joseph_newcomer

Here are two parts that need to be joined by magnets.  One of the problems with neodymium magnets is that they can pull out of a 3D-printed part.  So the green part has the magnets inserted from the back, with a 1mm separation from the surface.  The magnets are cubical, so I want to put magnets in the bottom.  The problem is that the loft makes it difficult to put the magnets in.  So I decided to create slots in the sides, 1mm below the surface.  The problem is, how do I make a 10-point circular pattern of a removal extrusion.  I ended up creating a square part that extrudes down to the correct depth, and replicating that.  I figured that I could then change the extrusion from "New" to "Remove", but in fact that doesn't work.  So what is the way to get a circular pattern of a remove extrusion?
The share link is 

https://cad.onshape.com/documents/1daeeea5e1cf8833755c740e/w/b37b57bff5de268c35cdd287/e/26805beab2671529cb55e1bb?renderMode=2&uiState=6224bb164926c6388b204883

(I thought of one way to do it: put down a layer 1mm + magnet thickness deep, cut the extrusions from that, and then put the rest of the circular part on top.  But I'm going to go to bed and will work on that later tonight).

eric_pesty

Looks like you figure out a way to do it with a boolean.
Otherwise you would have to do a feature pattern rather than a part pattern (and check the "apply per instance") in the pattern. Or a "face" pattern would probably work as well.

MrNoble

Found this trying to solve a similar problem - like @eric_pesty said, you need to use a boolean.
I'm going to go into a little more detail incase any other newbies are looking for a solution.
1) Instead of "removing" the extrusion for your first slot, make a new part that overlaps.
2) Use circular pattern to copy the part.
3) Use the boolean tool to perform a subtraction.

Here's the model I was trying to puzzle out, so you can see it in action.
https://cad.onshape.com/documents/addaabb1562ebd8308676e61/w/798b334375a9774fafef87be/e/84b64b7d70b0b67875753aee?renderMode=0&uiState=661997d8f1fe67209755edc3

rick_randall

eric_pesty said:

Looks like you figure out a way to do it with a boolean.
Otherwise you would have to do a feature pattern rather than a part pattern (and check the "apply per instance") in the pattern. Or a "face" pattern would probably work as well.

I think "feature pattern" is the way to go - make one pocket (extrude subtract) Then circular pattern that feature (all will be a subtract)