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Redundant constraint, why? (by Mark Chambers)
Please refer to the attached model.
I'm trying to fix the height of the heatsink against the pcb.
It currently has 2 degrees of freedom and I want to reduce it to 1. When I try to set the distance between the center point of the heatsink closest to the pcb and the top edge of the spacer behind the vertical component, I get a redundant constraint error. Why is this redundant? Thanks
Mon Sep 2 2019, 17:30:16, download attachment assembly 3.slvs
(no subject) (by Andrew)
When you have external dependencies, you need to zip up all the files otherwise the file will not be useful, which allows you to attach all files as a single file.

Anyhow, as to constraints, they will drive you mad until you get the swing of the. But in essence, a point is a triple constraint, a line is a double constraint, and a surface is a single constraint. To reduce degrees of freedom by one, you need to constrain to a plane, or use a length constraint, either same length, or actual length. Alternatively, you can allow redundant constraints. Note, the conflicting constraints will be listed in the text window, and can be selected by clicking om them there.
Mon Sep 2 2019, 18:32:14
(no subject) (by Mark Chambers)
Please see the attached zip archive.
I understand about the point/line/plane restraints degrees of freedom. What I don't understand is why adding the length restraint, either from the top of the heatsink to the top of the spacer block or from the bottom of the heatsink to the bottom edge of the chassis) results in a redundant restraints error. Allowing redundant constraints doesn't fix the issue either; same error. Thanks
Wed Sep 4 2019, 13:08:10, download attachment assembly 3.zip
(no subject) (by Andrew)
When setting constraints, you should be constraining and object in the active group against the rest of the drawing, Make the heatsink group active and you can add constraints to the chassis. The error you are getting is because neither of you selections for constraints is in the currently active group.
Wed Sep 4 2019, 13:51:27
(no subject) (by Mark Chambers)
Your suggestion does not work on my system. I'm using SolveSpace version 2.3~7c1ca460 under Windows 7 Pro.
The fix I found was to first place and constrain the heatsinks then to bring in the pcb assemblies and constrain them to the heatsinks. But thanks nonetheless.
Fri Sep 6 2019, 13:43:23
(no subject) (by Maurizio Ferreira)
If you want to anchor the heatsink to the pcb, you have to first include the pcb, position it and anchor it some way to the already placed component, (chassis) and only then you can include the heatsink, and anchor it to the already inserted components (to the pcb or to the chassis), but only to one of them,unless you allow redundant constraints.
Tue Sep 10 2019, 11:20:26, download attachment Assembly3-modified.zip
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