Cure for excessive weather helm


#1

I’d like to know your thoughts on curing excessive weather helm?


#2

Don’t have a cure for it, sorry. But the article you have posted on Taleisin says that the original bowsprit was shorter, and that Larry increased it’s length to cure some weather helm. I thought this was interesting because the Falmouth 34 sister ships, one of the last boats designed by Lyle Hess, were also designed with shorter bowsprits, and all were lengthened to cure weather helm. If I remember correctly the F34 builder, Bryan Gittins, said something to the effect that Lyle didn’t like long bowsprits.


#3

I don’t suffer weather helm to badly and my bowsprit is longer than some. I will see some WH if on a beam reach in 15knots of wind.
Excessive heel generates WH in BCCs so reefing the main early helps to keep the boat flat
The BCC has a large mainsail in proportion so reefing seems to be a cure for much bad behaviour and helps maintain balance
When I first bought Takayna the sails had seen a lot of use and were blown out and baggy. Weather helm could be shocking. I had new sails made before I left for Tassie and they have made a huge difference. The new main is cut very flat and works really well
Jono


#4

Thanks time and Jono for your thoughts!

OK… so I’ll write a bigger post on this on BristolChannelCutter.org but Ubique just got an extra 1000mm of bowsprit, and I can report that there was a difference. Not as much as I expected (it hasn’t cleared the problem) but it definitely has helped.

Interestingly, at the Australian Wooden Boat Festival in Hobart we were lucky enough to host legendary boat rigger, Brion Toss, for a 4 hour sail (he wrote several bibles on the matter of rigging). He explained that the bowsprit was one component, but there were several others - mainly around raked spreaders, shroud tension and sail shape (as Jono mentioned in his post).

Love to hear other people’s experience, and let’s see if we can find a definitive series of solutions for this problem which seems to plague a few BCCs.

Oh… and in addition, Chris (the previous owner of Ubique) suggested that the rudder was too big. This definitely has merit considering both April of Cygnet (Hey Gary !!), Jono’ s boat Takayna, and Gus’s Friendly Light all have a parallel rudder stock (i.e. not curved / flared to match the keel lines).
Does anyone else agree?

I’m leaning towards perhaps sail shape after meeting with Brion - also because when we triple reef yet run both head sails, all weather helm disappears!

Let me know what you guys think!
Dave


#5

I”m not sure how rudder size would contribute to weatherhelm. My (limited) understanding of the causes of weather helm, and yes there are many, is often to do with sail area aft of the centre of effort pushing the head up to windward. That’s why reefing is always my first action if WH gets bad. In that situation it seems the bigger your rudder to counter that pushing force would be an advantage. Often the rudder is being overpowered in gusts that will cause the boat to head up
There may be an element of the rudder stalling hydro dynamically but I know nothing about that or how size may or may not help
As always I could be talking out of my arse so ignore at your pleasure
Jono


#6

Hey Jono,

Great to catch up with you and Takayna this weekend down here in Tassie.
After our discussions (and with Brion Toss when he was on board), I think you’re right - it’s probably not the rudder size after all.
Especially considering that if we triple reef and run both head sails, then Ubique tends to feel quite balanced.

New bowsprit has definitely made a difference though.
In 15 knots with full canvas she steered herself nicely close hauled without hands on the tiller.
First time that’s happened since we got her.

I’ll keep working on it, but as Brion said when he sailed on her, it’s likely to be a number of small things all contributing.


#7

I had some weather helm in my Tashiba 31, which also has a cutter rig and bowsprit. I adjust the rake of the mast, which made a small difference. But what finally fixed it was a new jib and staysail. The mainsail was fully battened and still had some shape, but the original jib and staysail were not pulling their weight, so to speak.


#8

Hey timg,

Yup, I agree that new sails will likely make a big difference… now where’s that spare $15,000 I stashed under the mattress…

:o)

Better start saving!


#9

Won’t cost you that much surely? My new main and staysail, plus boom bag and staysail bag cost me au$6.5k.
Ubique would looooove a new mainsail. I reckon she’d be a new boat and she thank you for it


#10

Jono, who did you get those sails from again? Was it North Sails?


#11

Andrew Turner at Ullman Sails in Brisbane. North sails not interested in my little sails. They want to sell big carbon ones. I think Andrew did a good job, made a huge difference to how well we sail