Weld is causing parts to fling?

Help and Feedback Building Support
#1

I am trying to create a light rail system with a TweenService, and I’m trying to weld the base part that’ll house the seats to the slide that I’m using as a primarypart, however when I try to weld it this happens:
[https://gyazo.com/63285709d023184aa2adaa5a59e06d86]

I even tried setting the C0 and C1 programmatically with:

local TrolleyWeld = Instance.new("Weld", TrolleyObject.Slide)
TrolleyWeld.C0 = TrolleyObject.Slide.CFrame
TrolleyWeld.C1 = TrolleyObject.Base.CFrame

TrolleyWeld.Part0 = TrolleyObject.Slide
TrolleyWeld.Part1 = TrolleyObject.Base

However, that gives me:
[https://gyazo.com/9013bb8deadf13556f9e217506d34645]

Obviously it’s holding the same CFrame as the initial value I’ve set in this case. Is there any better way of doing what I’m trying to do? I eventually will 3D model a trolley from the base but I’d like to get the basic mechanics done but can’t figure out this weld. TIA!

#2

Figured it out. When I was adjusting the position I didn’t realize that using .Position instead of .CFrame it doesn’t respect welds. Just set the CFrame instead.