Finn Mainsail

[ent228]

Hi, I've just run an old North sail up my battered 3B mast only to find that the cunningham pulley contacts the end of the sail track before the headboard is fully up. It makes getting the sail right up really difficult.

On my last Finn this didn't happen and it had an identical mast. Is the mainsail luff too short, or is it OK, or shall I lop a foot off the bottom of the sail track or get a different sail. What do you think?

[PeterV]

I've a couple of thoughts. Firstly many Finn sails were made with stretchy luffs, if yours is like this then I wouldn't cut the track back, just pull the halyard hard to get the sail up and the halyard into the lock. It's common for the mast to bend quite a lot at the top as you pull it up hard becasue of the tension in the halyard and luff.
Secondly if the luff isn't stretchy then they can shrink with age. You should be able to determine if this is the case by seeing if you can pull the tack right down to the boom when the sail is up at the top. If you cannot then you'll probably need to get a sail maker to free the sail from the luff rope and extend the luff rope a bit.
If neither of the above is the case then it's possible that the sail is cut with a higher cunningham than the mast track is allowing for and I would cut the track back. The 3B is a very early mast (in fact the first popular alloy Finn mast, as supplied for the 1972 olympics) and North sails didn't start to become popular until the later, round 3M came out. I've just measured my 3M mast and the track starts 56cm above the boom pin, so if yours starts much lower then it's the mast, not the sail that's the problem.

[ent228]

Thanks Peter,

Really good info and measurement. I'll go out and measure it.

[Pat]

We had this on a Lark sail and were told by one of the P&B team that the bolt rope is secured at the bottom but not all the way up so unpick the bottom bit and it frees up a lot. Worked for us! Just leaves a bit of luff without rope.
Other luffs are really elastic and can be pulled into place as Peter suggests.

[Ancient Geek]

Which is why the worlds best sailmakers (North of course.) Leave the bolt rope in a loosish pocket and over long hanging out the bottom in a sort of tail. But it does what modern bolt ropes need to stop it pulling out of the luff -foot-groove

[ent228]

My mast has the same measurement from boom pin to bottom of sail track, so it's the sail. I will go and experiment.