How to weld specific things with a script?

I have a boat, welded with crazyman32's welding script, But when I add the paddles that are required to make it move on roblox water, It just freezes in the air.

I'm thinking its something to do with the paddles and weld script that can be found here

If anyone could give me an alternative way that isnt changing the surfaces of the blocks to 'Weld' that would be much appreciated... (I have tried grouping different things together, But the weld script may be interfearing with the hinges, which maybe why its not working, Dont know how to fix this)