I've just bought a pair of Lewmar 30 self-tailing sheet winches. I've never used self-tailers before so what are your recommendations for type of rope to use - construction, size (8-12mm), manufacturer etc?
Typically, 12mm would be good for that size of boat/winch... massively large enough from a strength point of view, but also large enough to be comfortable to handle..... 10mm would be fine, but I don't like 10mm for regular handling... it can be hard on the hands...... agree with TK about rope type.... plain braid on braid would be perfect...
I use 10mm on my '26' which is fine for handling and weight and I only have size 16ST's.
I tried a smaller diameter Dyneema but it kinked very easily as the return from the cockpit coaming turning block back to the primary winch inevitably puts a twist in the line- so I've discontinued that.
I now have a 10mm polyester braid on braid which still kinks a little if the twist isn't taken out on each tack BUT it runs more easily through the genoa cars . Also I've done away with knots/shackles at the clew as these hung up on my babstay- so if you have one of these then try a spliced soft eye in each end of the genoa sheet and I then use a Dyneema 'rope shackle' from Compass 24 which provides a neat and safe fastening which doesn't obstruct. In fact even with no babstay I would now use this system as it looks neat and won't cause you injury if you have to attend to a flogging clew on the foredeck.
A final note, the coaming turning block and genoa car and friction from guardwires in light winds provide a surprising amount of resistance to free running genoa sheets, so the thinner and more slippery you can tolerate sheets the better, to achieve a reasonable sail shape in such conditions