Pocketing Odd Shapes

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dave_w
Posts: 89
Joined: Thu Mar 12, 2020 12:37 am

Pocketing Odd Shapes

Postby dave_w » Mon Apr 06, 2020 6:46 pm

Hi All,

I've searched the forum and don't see anything about this. (I could be using the wrong search terms though.)

I have an odd shape that I want to pocket. It would be painful to recreate the shape with smaller dimensions to pocket it, especially since it has arcs of different radii. Is there a better way to do this?

For example, lets say you have a 4 leaf clover that you want to pocket. You start by drawing the 4 leaf clover, then padding it. I'm looking for the easy way to pocket that without having a new drawing with a smaller 4 leaf clover. Do-able?

Thanks,

Dave

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kisolre
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Re: Pocketing Odd Shapes

Postby kisolre » Mon Apr 06, 2020 6:51 pm

If I understand correctly you want PartDesign Thickness or Part Thickness. You could also try Part_CompOffsetTools to create offset solid and difference it or create offset sketch and pocket it.
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Willem
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Re: Pocketing Odd Shapes

Postby Willem » Mon Apr 06, 2020 6:55 pm

If I understand what you want I think you can make a Draft Clone of the Sketch or the Pad and scale it
dave_w
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Re: Pocketing Odd Shapes

Postby dave_w » Mon Apr 06, 2020 10:37 pm

Willem wrote:
Mon Apr 06, 2020 6:55 pm
If I understand what you want I think you can make a Draft Clone of the Sketch or the Pad and scale it
Thanks for the suggestion Willem. I don't think this works though. It scales all the dimensions which makes the part smaller.

Dave
dave_w
Posts: 89
Joined: Thu Mar 12, 2020 12:37 am

Re: Pocketing Odd Shapes

Postby dave_w » Mon Apr 06, 2020 11:27 pm

kisolre wrote:
Mon Apr 06, 2020 6:51 pm
If I understand correctly you want PartDesign Thickness or Part Thickness. You could also try Part_CompOffsetTools to create offset solid and difference it or create offset sketch and pocket it.
Hi (again) kisolre,

This does give results similar to what I'm looking for. I can the Draft tools to create a 2D offset under the Part menu that is smaller than my Sketch outline. This is exactly the affect I'm looking for. Now I have the sketch of the body and the 2D sketch of the smaller body and want to pocket it, but don't see how to do that with the 2D. The Offset2D and sub Sketch are under the Body of the part, and not the Pad. Nothing I've tried pockets the inside of the part (and I can only get the 2D sketch on the xy plane, not the top plane).

I'll keep trying...

Thanks,

Dave
kisolre
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Re: Pocketing Odd Shapes

Postby kisolre » Tue Apr 07, 2020 12:09 am

It would be easy if you provided a file. This way we know exactly what you are dealing with and most of the guess work is eliminated.
freedman
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Re: Pocketing Odd Shapes

Postby freedman » Tue Apr 07, 2020 12:29 am

In draft do (see pic). Also in draft I turn the grid off before I exit. This icon will give you a sketch, drag that into a body and your ready.
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dave_w
Posts: 89
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Re: Pocketing Odd Shapes

Postby dave_w » Tue Apr 07, 2020 12:55 am

kisolre wrote:
Tue Apr 07, 2020 12:09 am
It would be easy if you provided a file. This way we know exactly what you are dealing with and most of the guess work is eliminated.
Couldn't see freedman's picture. ?

Of course it would be easier to post a design.

Here is a part I've been working on. It's similar to what I'll want eventually, with a pocket on that shape and 4 holes. The dimensions will change a lot (waiting on my digital calipers to measure properly) as will probably the various arcs. The only thing that will remain the same is the basic 3 lobe design. (Note that I've removed the holes to try to create the smaller pocket. I even tried to remove the pad and see if I could create a smaller sketch with the offset tool, then move to a padded and pocketed part. Didn't get there either.)

Thanks,

Dave
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freedman
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Re: Pocketing Odd Shapes

Postby freedman » Tue Apr 07, 2020 6:21 am

When sketching you need to make sure the connections (between 2 lines) are valid. While out of sketcher, select your sketch in the tree and then goto the toolbar and select Part design-Validate Sketch, go thru the list and check for errors. You have some on this sketch.
dave_w
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Re: Pocketing Odd Shapes

Postby dave_w » Tue Apr 07, 2020 6:32 am

freedman wrote:
Tue Apr 07, 2020 6:21 am
When sketching you need to make sure the connections (between 2 lines) are valid. While out of sketcher, select your sketch in the tree and then goto the toolbar and select Part design-Validate Sketch, go thru the list and check for errors. You have some on this sketch.
Got it, thanks! You've taught me one more thing. I expected that since I could pad and passed the broken sketch rule that the sketch would be OK. Guess not always.

I'll get back to the offset attempts in the morning.

Thanks again freedman!

Dave