[Solved] Changing Sketch offset causes Revolve to Disappear

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PAS_Drafter
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Re: Changing Sketch offset causes Revolve to Disappear

Post by PAS_Drafter »

Syres wrote: Fri Jan 28, 2022 8:43 am I think you may have come across a bug which also resides in 0.20 current master but this is still to be definitely confirmed. In the meantime have a look at the way I'd model it even without knowing about the possible bug in the attached file. Mirrors and Patterns are your friend in the main.
I had tried to use a mirror but I ran into problems with it failing there too. I have the drawing linked to the Y axis so I thought it should mirror okay. You mirror the full left and right tail. I even tried putting a little tail on my "half" drawing to go past the Y axis and got the same error.

MirrorFail.PNG
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Clevis_Shackle2.FCStd
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GeneFC
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Re: Changing Sketch offset causes Revolve to Disappear

Post by GeneFC »

You need to select both the Additive Pipe and the Revolution before the Mirror operation. (Or add in the dialog.)

Shackle.JPG
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Gene
chrisb
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Re: Changing Sketch offset causes Revolve to Disappear

Post by chrisb »

Mirroring the Revolution is obviously not enough, you have to mirror all previous features. General approach: If you have a body with many features, you should consider to use a Part mirror on the whole body. That function is still missing in PartDesign.
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drmacro
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Re: Changing Sketch offset causes Revolve to Disappear

Post by drmacro »

chrisb wrote: Fri Jan 28, 2022 6:12 pm Mirroring the Revolution is obviously not enough, you have to mirror all previous features. General approach: If you have a body with many features, you should consider to use a Part mirror on the whole body. That function is still missing in PartDesign.
It is easy to see why someone would see the current tip and, armed with the concept that the tip represents the current state of the solid, select it and be confused what it doesn't mirror. Missing the subtlety of the tooltip that says "Create a mirrored feature"...the operative word being "feature". 8-)
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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Shalmeneser
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Re: Changing Sketch offset causes Revolve to Disappear

Post by Shalmeneser »

Code: Select all

 └ Body (Body)
    ├ AdditivePipe (AdditivePipe)
    │  ├ Sketch001 (Sketch)
    │  └ Sketch (Sketch)
    ├ Revolution (Revolution)
    │  └ Sketch004 (Sketch)
    ├ Mirrored (Mirrored)
    └ Pocket (Pocket)
       └ Sketch006 (Sketch)
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PAS_Drafter
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Re: Changing Sketch offset causes Revolve to Disappear

Post by PAS_Drafter »

OOOOOOHHHHHHH!!!, That now makes sense to me.

I did think that it was mirroring everything from the Tip down and not just the Revolution. Now I see why it didn't work.


THANKS everyone for your help. I keep learning and getting better with it.
TheMarkster
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Re: Changing Sketch offset causes Revolve to Disappear

Post by TheMarkster »

drmacro wrote: Fri Jan 28, 2022 6:17 pm
chrisb wrote: Fri Jan 28, 2022 6:12 pm Mirroring the Revolution is obviously not enough, you have to mirror all previous features. General approach: If you have a body with many features, you should consider to use a Part mirror on the whole body. That function is still missing in PartDesign.
It is easy to see why someone would see the current tip and, armed with the concept that the tip represents the current state of the solid, select it and be confused what it doesn't mirror. Missing the subtlety of the tooltip that says "Create a mirrored feature"...the operative word being "feature". 8-)
This is because each feature actually has 2 shapes associated with it: Shape (which is the boolean with all the previous features) and AddSubShape (which is what the pattern tools used when making the copies for the patterns, such as mirror or polar pattern). The AddSubShape, which I refer to as the Pattern Shape in PDWrapper, is the intrinsic shape of the object, for example with a pocket it would be the shape produced by extruding the sketch. Features which do not have this AddSubShape property, such as a polar pattern feature, cannot themselves be patterned. That's when you get the error message it needs to be an additive or subtractive feature to be transformed.
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