I had the same problem on my canoe.... my strips ended up being just the right length, and at the last inch or so I ended up with cracks I had to fill.

I noticed later that, I had run so many strips through, with so much pressure from the finger boards that I had worked a grove into one side of the router fence. Later when building my kayak I eliminated the problem, in part by putting on a plywood fence over the plastic one, to eliminate the grove.

I think I did something different with my feather boards to prevent the strip from turning into the router bit. I can not remember what it was though, I do not remember my first setup. I 'think' my first setup had the feather board over the router bit, or the slot it fit in on the fence. I changed that, using two boards on either side of the bit, and possible a third 'board' (just another strip) to hold the strip into the fence at the far end of it.

Hmmm... really, I used to have a good memory.

Myrl.