I believe but I'm not sure, but the tool that you usually use for that type of project would be a lathe. The lathe will spin the block of wood at high speed and you'll use the hand tools and shave the wood off.
If you don't have a lathe, or your not looking to buy one. I'm sure you could use a stick of dowel and round over the ends.
I'm no really sure if a router can do such an operation, but it could be possible. Tommorrow I'll get a confirmed answer from Bob or Rick. Hope this helps
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