Solution to In-Mast Furling Problem

[CatCaptain]

May be a bit bold title, but after 5 years with tricky in-mast furling issues my current solution is a great relief. It is all about friction.
My rig is a Zspars UK on a Prout 39 feet catamaran. The rig design is "Prout Offshore Rig" witch means that the mast is far back on the boat; 6m from the bow, the boom is 3m. The production year is 1998 and I never changed any sails or standing rigging.
Even with this small mainsail the jamming inside the mast has been a increasing problem. I have tried all tricks in the book (web) Zspars description, easing the tensions, angling the boom, winching in with tension on the sail etc.

My first problem was that the line used for furling the sail had swollen from salt water and general use. When the line was furled in the plastic spiral in the mast as the sail was pulled out, the diameter of the spiral roll was bigger than the space inside the mast, increasing the friction for every turn. This was solved (some years ago) with replacing the line with a new 10mm diameter line.

Still the sail has jammed more every year. I consulted a mechanical designer I know (whom is not a sailor) when I started to realise that the inside of the mast where the sail was to be furled felt all corroded and similar to sanding paper.
After explaining how a in-mast furling system works ("roller window blind" in a alu-tube with a slot) he suggested that rather doing anything to the mast to coat the sail with a dry lubricant on the "outside". It would be a much larger surface that would not wear of so easy and reduce the friction coefficient in the system.

I coated the 12 year old sail with PTFE spray-cans, and guess what...

It worked perfectly!!

After 5 years of impossible power handling of a sail that newer would cooperate I now furl the main sail with my bare hands. Now winches, no hassle, no angling of the boom, no nothing. Just furls in and out as a dream.

I guess you could use any dry lubricant on the sail as long as the friction between the sail and the mast tube is reduced. I used 8 cans of PTFE spray from a local low cost store and could not be happier.



Fair Winds
CatSailor - Now with both Genoa and Mainsail in use, even for a short leg.

[Pete7]

Interesting, is a 12 year old sail getting on a bit and therefore most folk would have likely replaced by then so have avoided the problem. Doesn't a sail loose "the fill" over time, which is what makes them smooth and slippery when new? certainly our recently purchased newish genoa we picked up is much more slippery compared to our existing old genoa.

Pete

[FraidNot]

what the heck is PTFE ??

[Vasco]

Teflon

[CaptainBW]

Glad you solved your problem CatCaptain, and it begs a question...is in-mast furling reallly the way to go?

My only experience with it was when bareboating in the BVI. The furler was extremely temperamental and we had difficluties each time we used it.

I am currently looking at an Island Packet 370 with furling in the mast and I am concerned about it. Is my experience consistent with others who have this feature?

[DeepFrz]

CaptainBW;
We have had the discussion at least several times about in mast furling. Check the threads listed at the bottom of this page for further discussion. Also do a search for in boom furling for even more discussion.

[Bash]

Originally Posted by CaptainBW

I am currently looking at an Island Packet 370 with furling in the mast and I am concerned about it. Is my experience consistent with others who have this feature?

One of the things you might want to check was when the boat was designed. (Note: "designed," not "built.") If the boat was specifically designed for a furling rig, then you should not suffer a performance loss. I think the problem, early on, is that boats designed for conventional rigs were being fitted with furling rigs, and owners were suffering the loss of roach. That tends to be a thing of the past at this point.

I've had two boats with in-mast furling, and several boats without. If you're in a windy area where reefing is likely, in-mast furling is the bees knees, especially if you tend to sail short-handed. If I were to sail in areas with lighter air, I would probably opt to go with a conventional full-battened main on a batt-car system.

[CaptainBW]

DeepFrz, thanks for the heads up on the links at the bottom. One was spot on and had references to Island Packet boats to boot!

Bash, thanks for the feedback.

I feel much better about making the purchase with the in-mast system.

[FraidNot]

Do you think PTFE spray is 'safe' on all sail types?
I have a 'conventional' in mask furling system on my Beneteau 411 and I'd like to try this.