Editing a McMaster-Carr part. It only partially works.

[RogerInHawaii]

I imported a McMaster-Carr gear.

But I only want the gear part, not the shaft. So I created a sketch at the end of the shaft.

And used the extrude too to cut away the shaft.

The preview looked good, so I hit OK. but it didn't do anything. The whole gear was still there. ???

So I tried again, but this time I did the extrude cut back into the gear section as well.

And it did do a cut, but only of the gear section. It still left the shaft untouched.

Why? Why does an extrude cut NOT affect the shaft? Is there some magic characteristic that's been applied to the shaft that prohibits it from being cut, even though the preview of the extrude shows that it (presumably) going to be cut? And there's nothing in the gear component that indicates anything special.

[davebYYPCU]

Dependant on your preferences, a sketch created on a face, will project the face, but not draw its previously purple boundaries. (PITA)

You are selecting the bounding box, but not the area where the face is sitting,

in other words the extrude cut will only use the profile/s highlighted in blue. hide the gear, select all of the sketch profiles, unhide the gear, to continue.

[TrippyLighting]

Can you share the part number ?

there are other ways to do this. Whether they are better is a question (I think so).

De-featuring this in direct modeling mode might just be the ticket to accomplish this.

[chrisplyler]

Some McMaster-Carr items contain multiple Components. If that's true of this gear, do you have the appropriate Shaft Component activated when you try to perform the Extrude/cut?

[etfrench]

The "shaft" is called a boss

@davebYYPCU's post is probably the correct answer.

Split body could also be used.

[TheCADWhisperer]

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@RogerInHawaii wrote:

The preview looked good, so I hit OK. but it didn't do anything..

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Your Preview should look more like this (select areas 1 and 2).

[lichtzeichenanlage]

Have you imported the design as STP/STEP file? After doing that, it should work like this:

[zodiaceng]

Edit your feature and select inside the circle as well. It's only selecting the outside of the circle that was projected to the surface during the sketch creation.