I used a random orbital sander to knock off the corners of the outwales, inwales, and spray rails on my Peeler Skiff.  A rasp worked fine but was no faster and still required sanding.  A long smooth stroke worked best.  Use a fine grit to round plywood.

���Ah, love tool discussions....Dremel with stone smaller than space made by the inner rails, I also had a small hand held trim router with a 1/8" round over bit with a pilot bearing on the end...old belt sander belts torn into 1" wide strips and hold it by each end and pull it back and forth like the old way of polishing shoes, and wrapping sticky back sandpaper around a round file.. Curt

 On my Skerry I used a regular router with a piloted round-over bit for the outside edges of the rails (3/8" or 1/2" radius - don't recall which).  I just worked very carefully, and the results were perfectly satisfactory.

For the inner edge of the shear strake, and also for the corners of the seats and the exposed edges of the bulkheads, I used a Dremel 1/8" radius roundover bit.  I picked up an old style Dremel router attachment on eBay, which is much simpler than the ones they sell now.  However, the diameter of the flat base was large enough that it wouldn't sit flat on the top of the rails, so I made my own smaller base out of a scrap of masonite.  The only trick was to keep the Dremel router moving, because unlike the ball bearing pilot on a full sized router bit, the pilot on the Dremel roundover bit spins with the bit and will actually burn the wood if you don't keep the Dremel tool moving.  The work went quickly and all my rounded edges are perfectly uniform.

   The router attachment I used was a Dremel Model 230.  Much simpler than the complicated ones they sell today.

hokker

I just used a block plane and 80 grit sandpaper for rounding over my rails.  It took about an hour and a half to do the outside and inside rails, top and bottom.  But I do a lot of hand planing in my woodworking, so I might be faster than some.  One key is the depth of cut - set it as deep as you can while still getting a good quality cut.  Also, a razor sharp blade is a must - as they say, sharp fixes most everything.  :)

A router is definitely faster - I just enjoy the handwork and the lack of noise and dust.

Cheers

Dave

I used a trim router which has about a 4" square base with a 1/4 " roundover bit.  With its bearing on the bottom of the router -- any slip will take the cutter away from the rail, so not much chance of marring the rail.

Dave M. 

   Your’e right about sharp corners Phalsey. Won’t hold epoxy or varnish well, sharp corners are vulnerable to all kinds of impacts and they’re dang hard on your fingers and shins.

For what it’s worth, I tend to prefer chamfers to round overs. To my eye the facet catches light better and it looks less machiney. Struck lines on the rail about 3/8 inch down from top and in from outside edge. Makes about a 1/2” chamfer with little block plane work. Hogged off pretty coarse shavings at first with successively lighter cuts till it was smooth. The mahogany planes nicely. I prefer this method over rasps but won't make value judments over methods. However, that still leaves you with 45 degree corners. I made sure to dob them over just a little bit when sanding.
As much as I hate the screaming router, I did use a little trim jobby fitted with 1/4” radius pilot bearing bit - set a little shallow - for all exposed plywood edges and underside of rail. The shallow bit makes an asymmetric corner that’s more pleasing to my eye.
Cheers,
ev

   For the record, I'm having really good results using block plane, spokeshave and wood file for the rough out. Finishing with hand sanding. Thanks for all the suggestions!

Thanks for the followup.  Few of us bother to report back how things turned out.  It's really helpful.