Scale a clone or a better way to copy and scale a body?

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thomasa88
Posts: 2
Joined: Sun Oct 10, 2021 6:11 am

Scale a clone or a better way to copy and scale a body?

Post by thomasa88 »

Hi, I'm very new to Freecad, not parametric CAD.

I have managed to create a sketch and a body in the PartDesign workbench.

Now I want to copy my body, shrink it by 10%, offset it from the original body and combine them into one.

I've gotten this far:
* Sketch
* Pad -> Body "Big"
* Clone the body into the body "Small" and position it in the same operation

Now I try to apply MultiTransform -> Scaled to my Small, but I get the following error:
"Only additive and subtractive features can be transformed"

Is this because the size of Small is linked to Big? What is the correct way to do this? I want the 10% scaling to apply if I resize Big.

freecad_clone.png
freecad_clone.png (63.77 KiB) Viewed 1931 times

edit.
I think I found a way. Is it good? And how do I combine the bodies? I tried Boolean->Fuse, but Big got a red exclamation mark ("Tip shape is empty") in the Model tree and nothing is rendered.

* Sketch
* Pad -> Body "Big"
* Go to Draft workbench
* Use Scale tool. I did not select Copy in the enter point form. Is elected Clone on the factor/scale form.
* Go back to PartDesign
* Double click the new body to edit position.
* (How to combine??)
chrisb
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Posts: 53922
Joined: Tue Mar 17, 2015 9:14 am

Re: Scale a clone or a better way to copy and scale a body?

Post by chrisb »

Scaling is rather uncommon in parametric design. If you really need it, I would rather recommend the Draft->Clone command and use then a Part Fusion, but that means to leave the PartDesign world which bears other difficulties for newbies.

You may tell us instead what you finally want to achieve so that we see the whole picture. You may then get better recommendations. From what I see, your way of modeling is rather uncommon.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
thomasa88
Posts: 2
Joined: Sun Oct 10, 2021 6:11 am

Re: Scale a clone or a better way to copy and scale a body?

Post by thomasa88 »

Thanks for your quick reply. (I made the post, it was waiting for moderation and then I never saw the notification.. spam filter?)

I realized this morning that it is indeed a strange thing to do. My plan was to create the two boxes (actually a bit more complex shapes, but not very), have one scaled, shifted both sidewise and a bit in depth and then unified.

I think I will do this instead: Sketch both shapes, side-by-side and then pad them to different depths using planes as references.
TheMarkster
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Posts: 5505
Joined: Thu Apr 05, 2018 1:53 am

Re: Scale a clone or a better way to copy and scale a body?

Post by TheMarkster »

With PDWrapper (the rule breaker macro) (install from the tools menu -> addon manager) you could bring the clone into the Body as an additive type. Or maybe subtractive or common or XOR type would be better depending on your objective.

Additive type:
Snip macro screenshot-2255a1.png
Snip macro screenshot-2255a1.png (35.43 KiB) Viewed 1606 times
Subtractive type:
Snip macro screenshot-a28409.png
Snip macro screenshot-a28409.png (42.46 KiB) Viewed 1606 times
Common additive type:
Snip macro screenshot-469c02.png
Snip macro screenshot-469c02.png (41.37 KiB) Viewed 1606 times
XOR additive type:
Snip macro screenshot-9b8a99.png
Snip macro screenshot-9b8a99.png (47.73 KiB) Viewed 1606 times
With XOR additive the intersection is hollow, so technically there are 2 solids, which must be bridged in the next operation or it will fail.

PDWrapper also supports scaling and 3D offsetting. But the independent xyz scaling is buggy and needs work.
Attachments
pdwrapper_draft_clone_example.FCStd
(18.04 KiB) Downloaded 18 times
freedman
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Posts: 3440
Joined: Thu Mar 22, 2018 3:02 am
Location: Washington State, USA

Re: Scale a clone or a better way to copy and scale a body?

Post by freedman »

You can use a link to do this, they do scaling very well. Model one box and make a link,transform the link, then set the scale of the link using the properties panel.
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