Hey guys I am getting this annoying behaviour on weld constraints, when unanchoring it just changes everything position.
Hey guys I am getting this annoying behaviour on weld constraints, when unanchoring it just changes everything position.
Weld constraints are nice and simple but sacrifice the ability to actually control what you want them to do for that simplicity
Aka they usually have a mind of their own
I would personally just use a script to automatically weld together all of the non-moving parts (so skip the wheels, steering wheel or smthn, if you have spedometer gauges, pedals, etc, only weld the stuff that wont move), but some people arent really comfortable with that
In the case that you want to use that approach, you can pretty easily use the current cframes of each part to make a weld that will hold it in place
Heres one way to do that:
--loop through all of the non moving parts, doing something like this for each:
local weld = Instance.new("Weld")
weld.Part0 = mainpart
weld.Part1 = currentpart --the current part youre welding in a loop
weld.C0 = mainpart.CFrame:Inverse() * currentpart.CFrame
weld.Parent = currentpart
I would typically do this at the start of the game so every time you slightly edit the model in game you dont have to redo the entire weld structure
The trouble isn’t that I can’t control the car, it’s just the car parts kind of find random positions.
All the cars are welded the same and I don’t get this issue but in this car particullary it just goes crazy 
By “control” I mean you cant control the crazy movements of the car parts because when using weldconstraints you cant specify a specific position you want the car part to go to (hence the weird random movement of the car parts) and roblox kinda just guesses a position that will hopefully probably work for what youre trying to do
This isnt the case for welds though, and you have full control over them
Sorry for not specifying
Alright, yeah I already knew how to use Weld and set the offcet etc, just didn’t knew Roblox guesses it on-game I thought it does that back-stage and kind of grabs an offset from there, I’ll try your solution and get back 
I mean Im exaggerating a bit when I say it just guesses a position, but it automatically assumes a lot about what youre trying to do and seems almost like its guessing in many cases
Theyre a useful tool for very specific things but I havent found them to be very reliable
Hey I solved it by re-welding all, seems some parts were welded improperly, but it’s fixed now.
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I’ve found that if you use the standard Studio Move and Rotate tools then WeldConstraints work fine, but if you use a Plugin and try moving or rotating the Parts you can have issues with them.
Not sure if its what happened to you, just an observation…
Hmm, well I used re-size plugin 
I’ve used the Studio Build Suite (SBS) plugin and when you select a Part to resize it the Part gets moved as well when its been welded.