Not redoing a model position/orientation after undoing a weld

Reproduction Steps

  1. Open this project:
    Baseplate.rbxl (102.7 KB)

  2. Insert a weld as shown in this video:

  3. Undo

Expected Behavior
Undo should reverse positions/orientations

Actual Behavior
Undo not reversing positions/orientations after welding parts

Issue Area: Studio
Issue Type: Display
Impact: High
Frequency: Constantly


This has been around God knows how long, I think you’re better off making clones to mess around with for now.

1 Like

Thanks for the report! We’ll follow up when we have an update for you.


After more than 1 year, nothing has been done about this bug…

Expected behavior (unfortunately).

This is just an architecturally ugly part of the engine to do with welds.

There are ways this could potentially be solved but they all come with such significant performance or memory overhead that it’s unlikely most developers would prefer that over having to deal with this edge case.

The recommended solution is to use WeldConstraint instead of Welds for new work where you want to explicitly specify joints, as WeldConstraint is designed to not have the same issue.