Yeah thanks - that's probably exactly what I need to do. I guess first question I have is about mating two pieces of the same line. It kind of sounds like you're using one that is slightly larger to cover the smaller line. Any issues with me mating two pieces of the same? And I'll probably try to find a similar line that I can practice on. Any recommendations for tools that I should get before starting?
A few random thoughts:
1) I find 1/4" line to be fine for most lines on our C-22's - halyards, reefing lines, outhaul, etc. Everything except for sheets that you handle constantly (I use 5/16" spinnaker sheets and 3/8" jib and main sheets).
Others will differ on that and prefer 5/16" for handling on some (or most) of those lines. Your call - modern line is plenty strong enough for the low loads on our little boats; the choice is about feel, and that's up to you.
2) Related to #1: I have a 1/4" tubular fid that I use occasionally (they're $7
here at SBO). You can buy a full set if you like, but I didn't find I needed the others. For most things, I prefer wire fids, and for those I just use pieces of a roll of wire I had laying around. It's about .035" diameter; anything close to that would work fine. For really tiny line, I have a bit of .020 piano wire bought off eBay.
3) There are two ways to end-to-end splice double-braid. A
full-strength end-to-end splice will produce a bulge in the line (which might or might not work for your halyards, depending on where the bulge will end up and what blocks it would have to run through). A constant diameter splice in double-braid is NOT full-strength. That splice is used for things like continuous-line furlers, where you need an endless loop that doesn't have a bulge. But for a halyard, you don't want to give up that much strength.
There are lots of other sources online, but
Samson's reference site is one place to start. Class I is normal Dacron line; Class 2 is line with a high-tech core (like Warpspeed). It requires different splices, because the strength of the line is very dependent on the core.
More answers to come when I have a few more minutes.