So first, the pregnant question becomes, how much rake do you normally carry in that main mast? That approx. rake angle will be needed before I can give a reasonable 'guestimate' reply and one based on generalized 'sailmakers data' for the F41.
Not exactly sure how to measure rake to be honest, but I got a lot!
Weather helm and balance be damned, it sure looks cool!
I'd say my rake is in line with the line drawings, so lets call it 7 degrees
Id need to know the construction of the mainsail ....
.... woven dacron sail cloth?
It's a lee sails sail, so yeah it's dacron-ish.
.... does this sail have a luff bolt rope (a three strand dacron rope inside a 'sleeve' at the luff?
could even be that there is an 'exposed' three strand 'rope' sewn directly to the luff ... yes/no?
The sail does have an exposed 3-strand bolt rope sewn on the luff but it also has sail slides that go into an internal track.
.... What is the luff length of the sail (my data book omits the F41)?
I=47 J=16 P=42 E=17 PY=24 EY=11
One caveat here is that my masts are aftermarket aluminum spars made by Spartech if I recall. The mizzen has different stay/shroud arrangements than standard and I don't honestly know if they're taller/shorter than stock. They "look" to be the same as other formosas and I don't think they're off the standard measurements by much if any.
.... How old (yrs.) is this sail?
Really old methinks. It was blown out and baggy when I bought the boat in 2007 and it had been for sale for 2 years. Previous owner sailed San-Diego to Alaska and PNW often.
.... and how much 'extra strain' do you add to the mainsail luff when 'raising' this (dacron?) mainsail?
.... if you don't 'stretch out' that bolt rope, explain briefly how you raise that mainsail.
Well I used to "just raise" it but after reading an excelent treatise of yours on "how to hoist an old mainsail" I now raise the sail as follows:
1: hoist sail until halyard is at the top of the mast and the luff has no wrinkles.
2: take a few extra turns on the halyard winch and continue to crank until one of three things happens:
1. I get a new hernia.
2. I break something expensive.
3. I pop a blood vessel in my eye.
Having said that, the reefing I did that caused the boom (which is level when the main is hoisted without reefs) to rise with reefing was back when I was "just" hoisting the mainsail without the extra cranking.
I'll be at the boat this weekend for pictures, since y'all have asked. Assuming it's not blowing hard at the slip I'll post what happens with the reefs. Any particular photo requests that would help in figuring out what is going on here??