Bodies absorbing other bodies from different parts.

[Scott_]

Hello everyone,

I'm experiencing an issue where bodies within parts are including bodies from other parts into themselves. I'm designing a guitar amp cab, which is pretty much just a box. I created the fron panel first, then added the bottom, then top, then one side. I created each as a new part and a new body in said part. Part Design Workbench, Create a new body and make it active, Create a new sketch, then close the sketch, select the face on an existing part upon which I wish to sketch, Set the 'support' of a sketch, do the sketch, Pad a selected sketch. Now, as I toggle the visibility of each part (or the single body within) it includes duplicates of the other parts that came before it.

This is the first part and the second part showing the overlap:

Screen Shot 2021-05-14 at 18.45.35.png (45.76 KiB) Viewed 415 times

It would guess that it's something to do with my 'Set the 'support' of a sketch approach. I used Inventor at school and am used to being able to click on a face of one part and sketch a different part so that's what I'm trying to do. Is there a better way to do this in FreeCAD? I did have to search around to find the approach I have been using, but I couldn't see an easier way of doing it. I'm also very open to advice about other better ways to approach this.

Thanks in advance,
Scott

OS: macOS 10.15
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24276 (Git)
Build type: Release
Branch: (HEAD detached at 0.19.1)
Hash: a88db11e0a908f6e38f92bfc5187b13ebe470438
Python version: 3.8.8
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.4.0
Locale: C/Default (C)

[chrisb]

Hi and welcome to the forum!

Without the file this is mere guesswork: You may have used references across body borders, which is not allowed. You should see "Links go out of allowed scope" warnings in report view, and the Dependency Graph shows the forbidden references in red.

If you want to reference things from other bodies: use a PartDesign ShapeBinder.

If there is only one body in the Part container: omit the container, it serves no purpose.

[Scott_]

Hi and welcome to the forum!

Without the file this is mere guesswork: You may have used references across body borders, which is not allowed. You should see "Links go out of allowed scope" warnings in report view, and the Dependency Graph shows the forbidden references in red.

If you want to reference things from other bodies: use a PartDesign ShapeBinder.

If there is only one body in the Part container: omit the container, it serves no purpose.

Hi chrisb,

Thanks for your prompt reply. I have remade the model following your advice and am exploring how best to use the Shapebinder tool. I'm also looking into datum planes as they seem to have a similar function for this application but also allow the plane to be offset from the surface from which it is derived.

-Scott

[chrisb]

I'm also looking into datum planes as they seem to have a similar function for this application but also allow the plane to be offset from the surface from which it is derived.

You can attach sketches in the same way like DatumPlanes, including the offset. DatumPlanes are helpful, if you have more than one sketch to place on them.