Extrude cut onto two different surfaces (ver2012)

I'm looking to cut a pocket into the side of a part. The side is actually two surfaces at an angle to each other with a fillet rad between them.

When extrude cutting I can use the offset from surface option but only from one of the surfaces. Searching I've found various methods but they all seem to only work when it's one continuous surface (like the side of a cylinder or cone)

I can cut the part in mastercam by projecting a toolpath onto the surfaces but I should be able to do it on the model but can't seem to find the correct answer

Here's a couple of screen caps of what it's trying to do and one from what I got mastercam to actually cut, the part is done but I'd like to learn how to do this to the model

Thanks

M

Quote:

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Originally Posted by Mooser

I'm looking to cut a pocket into the side of a part. The side is actually two surfaces at an angle to each other with a fillet rad between them.

When extrude cutting I can use the offset from surface option but only from one of the surfaces. Searching I've found various methods but they all seem to only work when it's one continuous surface (like the side of a cylinder or cone)

I can cut the part in mastercam by projecting a toolpath onto the surfaces but I should be able to do it on the model but can't seem to find the correct answer

Here's a couple of screen caps of what it's trying to do and one from what I got mastercam to actually cut, the part is done but I'd like to learn how to do this to the model

Thanks

M

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Merge all the surfaces you want to offset from prior to the extruded cut operation.

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Cool I think it worked, or at least something worked.
I knitted the three surfaces together and selected that as the offset from surface of the extrude cut.
I did have to hide the knitted surface as it created a separate "skin" which didn't actually cut but underneath was the "real" model with the pocket now in it.
Thanks, never would have stumbled across that
M

I spoke too soon
Worked on one side, didn't quite would on the other
When I select the offset from surface it projects the cut down and stays off (doesn't reach) the surface the cut amount (.125" in this case) but when I selected the reverse offset selection (like above which worked) it takes away all of the cut and doesn't do anything (fails to extrude-cut)
The settings seem the same as one the side that worked, any ideas?
M

See attached screen shot. This is SW2016 so your screen might look a little different, but not much.

SW is a hybrid modeller and does both solid and surface modeling. I used both in this example.

1) Create solid model of basic part.
2) Select the two planer faces and the fillet face. These are faces of the solid and not to be confused with surface
3) Use the surface offset command to create a surface at your desired depth of cut.
4) Use the solid extruded cut command with the up to surface option.

Pay attention to the upper part of the feature manager tree and notice there are two bodies in the model: one is the main "solid" body and the other is the "surface" body. If I were to continue work on the model, I would hide the surface to get it out of the way.

--Colin--
https://uploads.tapatalk-cdn.com/201...1a5c34a22b.jpg

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Thanks Colin that makes sense (actually I still think it should be able to do the offset from surface without having to create these other surfaces but maybe in some future version, like partial fillet rads....)
It wouldn't let me select the new surface until I extended it (as I see in your image) and then it accepted the extended surface as the "up-to"
I did hide the surface also
Thanks again
M

That's a really cool solution Colin, and thanks for sharing.
A method I've used is to sketch the depth of the the slot from the side view (convert lines + offset the same ones then trim), on a plane on the centreline of the slot, and extrude cut 2 directions, then add the fillets
Can get a little fiddly, but has been useful when I've been stuck trying to do similar tasks