Next time when you have a chance, borrow the traveller line from a club boat, rig it on your boat and see what happens. You'll see then if it's the line or something else. If it's something else, then isolate the next factor, and so on.Sometimes I borrow a club boat when I don't want to bring my own and I don't have the same issue with the club boats (using my same tiller).
Strange. But this is the key to further experimentation:Next time when you have a chance, borrow the traveller line from a club boat, rig it on your boat and see what happens. You'll see then if it's the line or something else. If it's something else, then isolate the next factor, and so on.
A stiffer line may be better as it deforms less under load, but there's probably not much practical difference because the traveller block doesn't deflect the line very much.
It certainly has, but that doesn't explain the original poster's different experiences with different boats.... getting your trav block to lock in at the most leeward position has a lot to do with your tacking technique.
Not the problem here. Read the original post again (emphasis mine):Make sure that full off, the vang has just about exactly 24" from center pin (at the mast attachment) to center pin of the vang key. If this is too long, then a full on vang may not be putting enough downward pressure on the boom to keep the boom from trying to move toward the center of the boat.
(The range of adjustment in the vang doesn't have much to do with max pin-to-pin distance anyway. The limiting factors are primary line length and primary purchase ratio.)Today I caught myself with too much vang on several times in an effort to pull the sail further out in light to moderate air.
Sounds like a very plausible explanation.I think the old line did have flat/worn spots that tended to let the block sort of rest in those spots.
Depends totally on the construction. Very soft rope doesn't like Clamcleats, so if you use single-braid Dyneema or Vectran, then 5 mm is the minimum. If you want to go thinner, you have to go double-braid with a hard cover, and if you then want to keep the stretch of a 5 mm, you have to choose more expensive materials than standard Dyneema/polyester.4mm line instead of 5mm?
The original traveller block was probably designed for 6 mm as 5 wasn't common at the time. Not a very relevant fact really.the traveler block is designed for the 5mm line.