Brass prop center hole needs reaming

[Praxis]

I bought a wholesale lot of new brass 3/16" props off ebay. The center hole seems a bit dirty. They will not slide onto a 3/16 stainless rod or the prop shaft. My 3/16" drill bit goes down them with little/no resistance and turns freely. I managed to clean one out with a rotary grinding stone, but it was a real PAIN. I had to remove a couple thousandths before they fit on the shaft. Any thoughts on something to speed the process up (I have two dozen left to do)?

[Praxis]

Any thoughts? I'm cleaning them up slowly... but anyone with some experience would be appreciated.

[JimClark]

if the drill goes thru them then seems to me the 3/16 SS rod may not be ground so it is round and the prop shaft may have some burs on it

[Praxis]

I had that thought too. I took a piece of 3/16 brass tube (what I use as an adapter for my one 4mm shaft boat). It doesn't fit in any of the "dirty" ones. It does fit in my other propellers that fit the 3/16 shaft properly.

Just for fun, I tested a couple of props and they are loose as all get-out on the 4mm shaft - so I'm pretty certain they're out-of-spec 3/16 bores.