Any way to fix my perfection weld for tools and others?

Soo i know i always take models and take out the tool welds but i need a perfect weld that fits any tool creation like a perfection weld Added into a tool then it doesnt break into peices i know how its like to deal with it so i need to q weld all of the things together heres that script i made i need fixing on it...

local prev local parts = script.Parent.Parent:GetChildren()

for i = 1,#parts do if (parts[i].className == "Part") or (parts[i].className == "WedgePart") or (parts[i].className == "Seat") or (parts[i].className == "VehicleSeat") or (parts[i].className == "CornerWedgePart") or (parts[i].className == "WedgePart") or (parts[i].className == "UnionOperation") then if (prev ~= nil)then local weld = Instance.new("Weld") weld.Part0 = 2 weld.Part1 weld.C0 weld.C1 weld.Parent end end end