Not sure whether I should post this here or on Docpal's recent post, but since I've contributed to this thread, figured I'd post here to continue that conversation. Here's what I've come up with for a masthead float. It's 3 24" lengths of 2.75" D pool noodle held in place with a nylon strap, and covered in a dacron sailcloth shroud that mounts to the sail track, in an effort to improve air flow around it (for whatever that's worth). Had I not miscalculated the volume, I'd have made these 6" longer - or 30" each. By my calculation though, each float currently provides ~16 pounds of flotation, or in the vicinity of 31 pounds total in seawater (I'm Way less bothered about turtling in a lake). Shroud, strap, ledgers, screws and noodles combined for one float weigh a little less than 10 oz.
I haven't yet sail tested the final version, but did sail with a prototype that lacked the shroud around to the mast track. If I had finely tuned racing skills I could offer a more critical review. Lacking that, I couldn't tell any difference in how the boat handled, and it didn't appear to have any effect on the telltales that I could discern. My plan is to simply leave them in place, and not give them much thought again.
This shows fir ledger strips, but I'm replacing them with 1/8" alum strips.
You may notice I'm missing my 3rd batten which is why the sail looks a bit frumpy there.