Designing a box shelf in freecad?

[DennisCA]

Hello, I come from a fusion perspective (getting tired of that scene for... reasons), and I am having trouble adjusting to the freecad way of doing things. I don't even know how they work. I've looked at some of the basic tutorials but they seem to be using mostly just work with a single object.

I am planning to make a simple shelf using different parts (butt joints only for now) and I started going at it in fusion fashion after watching two intro tutorials by flowwie.

The shelf for now is basically a box & boards that is made up by:

-2x 990x300x18mm sheets (top and bottom shelves)
-2x 120x300x18mm side pieces that connect the two shelves
-2x 25x100x400mm boards

Here is an image of the shelf in fusion, there are also cutouts on the back in that model, where the two boards will be attached, which is what will attach the shelf to the wall later. I made those by creating a sketch on top of the shelf, laying out where I wanted the cutouts and I extruded them. Then I did another extrusion to create the boards from the same sketch as new bodies.



I had planned to add more features to the shelf yet, make boards longer. I'd also like to add box joints and the like. But this felt like a simple excersize for me to try in Freecad for now.



So In Fusion I make the bottom shelf with a sketch and extrude, then I clone it and move it into position. So far it works the same with Freecad.

Next step in fusion, I create a sketch on the side of one shelf, the bottom one say. Then I would make a rectangular sketch and align it to the underlying faces of the two shelves, then I would extrude the part by 18mm and have a side piece. I would then clone this part as well and move it to the other side.

But in freecad I cannot do this, it doesn't react to the underlying geometry when I create a sketch. There is some other way parts are aligned in freecad? But how does one go about it working with multiple parts and aligning them? Searching on this issue isn't yet yielding insight for me. I thought I had it with shape binder, and I created one of those but it did not seem to make any difference.

I feel a bit stupid having to ask such a basic question.

P.S. I don't write this at the computer I have got freecad on, so I cannot give the about freecad info. but it's the latest stable Linkstage3 build (I heard it solved the topological naming problem, which is a big deal to me) in a Win64 PC. But I don't have a bug issue really, just a knowledge issue.

[chrisb]

Hi and welcome to the forum!

The sides would live in separate bodies (or a body and a clone). You reference the existing objects with a PartDesign ShapeBinder.

[Bance]

Sketcher_External

[papyblaise]

2 solutions: the 1st use PartWb and Sketcher to have separate boards
2nd with PartDesign, you have to make each board in separate bodies

[DennisCA]

Thanks for the tips. I wasn't able to get the shapebinder to work, but the external geometry tool did.



This is the data for my freecad version;
OS: Windows 10 Version 2004
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 2021.916.24301 +3861 (Git)
Build type: Release
Branch: LinkStage3
Hash: 1d5a2540702ccba56ac1f324103d2a3954e83a0f
Python version: 3.8.6+
Qt version: 5.15.2
Coin version: 4.0.1
OCC version: 7.5.0
Locale: English/United Kingdom (en_GB)

[chrisb]

Thanks for the tips. I wasn't able to get the shapebinder to work, but the external geometry tool did.

Then my - hopefully educated - guess is, that you have modeled it all in one body, i.e. as a single solid.

[Bance]

For separate pieces, and your workflow, you need both.

[DennisCA]

Thanks for the tips. I wasn't able to get the shapebinder to work, but the external geometry tool did.

Then my - hopefully educated - guess is, that you have modeled it all in one body, i.e. as a single solid.

I tried both ways with the shapebinder tool. I first created a new body after making the shelves and clone. Then I used the shapebinder tool while active in the new body. Then I created a sketch but was not able to get it to snap to or align to what I had selected. I'll try it again a few times.

[DennisCA]

For separate pieces, and your workflow, you need both.

Both shapebinder and the external geomtry tool you mean, could you explain how they differ and where I would want to use one over the other?

[Bance]

In PD you should not reference outside of the active body. If you have done this, use the Dependency graph tool to see the out of scope links!

So make the geometry available in the active body via shapebinder, then use the Sketcher external geom tool (on the shapebinder) to create the references.

There are other workflows......