SHAPING
Once the glue is set, the wider staves of the mast need to be tapered to match the original ladder bit. This is easy to do with a router fitted with a bearing bit.
If you don't have a router, that's not a problem, most of the taper can be cut off with a simple hand saw or jig saw, and the whole lot sanded to a nice finish. A belt sander is good for quickly removing material, but be careful that you don't get too aggressive with it. Finally, run a round router bit over the corners of the mast to give it a nice masty look!