Hello devforum,
I’m currently working on this large door for the little side project I’m working on right now.
However, I can’t remember how to make WeldConstraints work, I’ve tried anchoring/unanchoring and workarounds in scripts but nothing’s changing, the parts attached to either door just don’t move.
If it helps, for context: I’m moving the doors with TweenService.
Are you moving your parts with Position and not CFrame? If so, try switching to CFrame.
Also make sure the main part of your door is anchored, and anything welded to it isn’t.
Edit: Clarification, main part of each door is anchored, and anything welded to that specific door is unanchored.
Yea I was using .Position
Thanks for the help 
No problem! Good luck with your project.