I had trouble when I tried to use the tubing as the coupler. I wasn't smart enough to slice it and roll it so that it would fit. I struggled and struggled trying to insert it even after cutting the coupler's ends into 'V' shapes. I ended up using the wire from a large paperclip and made a staple similar to the ones on a leather belt. I used wire cutters to make it the correct length and used needle nose pliers to shape it. Then, poked a hole in each end of the tubing so that the staple could be attached. Joe, I like your idea and I would rather I didn't have that metal staple touching my machines.