I’m trying to put a tip or foot on a walking stick. I have the stick I want and I have the tip I want. The cross-section of the stick is oval and the tip is round.
I don’t have a lathe or access to one. Before I start just whittling at it, I thought I’d see if anyone here has a better idea.
Belt sander can do the whole thing. Helps to have one where the backing plate can be removed, allowing the belt to conform somewhat to the curvature of the workpiece, helping to avoid flat spots.
Coarse-grit belts can remove bulk material, fine belts can help with final profile matching between the tip and the cane.
I’ve worked square stock into round quite a bit, without using a lathe, by planing the corners (and the resulting ones) off with a hand plane, until the piece is effectively round, then sanding. I’ve also used the same procedure with a large belt sander, creating equal, ever-smaller facets.
I’ve made a stail engine/rounding plane for turning down the ends of walking sticks that are too big to fit in my rudimentary lathe. https://www.leevalley.com/en-gb/discover/what-is-it-articles/whatisit-witch
But just for a one off, whittling it down with a knife is the easy thing to do. Keep trying to fit the end on and cut off the bit where it gets stuck.