Chassis keeps falling apart when regenerated?

So I figured how to make realistic throttles, but now when I regen my chassis, well, it all falls apart. I have a weld script in but it just keeps falling apart.

The code in the regen is:

local Engine = script.Parent.Parent["Model"]
local CloneTrain = Engine:clone()
Button = script.Parent.Parent.WCSpawn

function spawnTrain()
    if Button.BrickColor == BrickColor.new(104) then
    local Model = CloneTrain:Clone()--Clones the backup so the script doesn't break
    Model:MakeJoints() --Makes it so the model doesn't fall apart.
        Model.Parent = game.Workspace --Puts the model into the game
    Button.BrickColor = BrickColor.new(26)
    wait(45)
    Button.BrickColor = BrickColor.new(104)
    end
end



script.Parent.ClickDetector.MouseClick:connect(spawnTrain)

Here are images:

Normal: https://gyazo.com/4f701374e6fed020144e29873ad3f97a

Regened: https://gyazo.com/9894b23d8f52114d3bc851fc618fbd26