gaff rig shrouds--tightness

[stevefalco]

I'm a novice sailor and have bought a 21 ft. long keel gaff sloop. Of the three shrouds on each side, two are lashed to the chainplates and the third has a rigging screw. How tight do the lashings need to be? I've pulled them as tight as I can, but of course there is a little stretch. Is that OK?

 

[Kukri]

Your'e fine. That's just right.

Lashings are good - safer and cheaper than rigging screws for this size of boat.

You may need to re-do them after a month or so - or after a good beat to windward, but a gale on the mooring will also stretch them.

 

[dur]

Welcome...

Tight as you can is probably spot on - which makes life easier! Then I guess set the pair with bottle screws to about the same. Then go around and see that they all deflect about the same. If they don't deflect its probably too tight. Having generalised tell us what the boat is, what it is made of etc etc and someone who really knows should be able to tell you.

 

[Peterduck]

You're only trying to stop the stick going over the side; they're not guitar-strings! Same with the bottle screws; just take the slack out and no more.
Peter.

 

[stevefalco]

Thanks for the info. The boat is a Harrison Butler Cyclone built in 1928. So, I'll just snug everything up well and go out on the Deben and learn to sail.

 

[Peterduck]

You're only saying that to make me envious, and it's working! Learning to sail in a Harrison Butler gaffer must be like learning to drive in a Jaguar or BMW.
Peter.

 

[Porthandbuoy]

An HB Cyclone!! Loverly.

Whatever you do, DON'T go tightening the leeward shrouds on alternate tacks!

 

[laurance]

Well there is a little more to said on the subject than has been suggested. See Cunliffe's Hand Reef and Steer for some sound advice, but try to to finish up with with your mast in column and your fore-stay properly supported by whatever shrouds are opposing it.
As for tightening the lee shrouds whilst sailing I confess to having done so regularly. It seems to me a perfectly reasonable cheat for minor adjustments provided one is aware of the danger of overdoing-it. Knox Johnston recommends doing the whole job of tuning whilst under sail in his book Seamanship, though I suspect this advice was aimed at the leg-o-mutton brigade.

 

[Kukri]

With respect, no, there isn't! /forums/images/graemlins/wink.gif

To quote Tom Cunliffe, "if you don't know why you should not harden up your lee shrouds under way, you should not own a wooden boat" - which is a bit extreme, and obviously, doesn't apply to Sir Robin K-J, but he's in a different class to most of us.

A gaff mast is going to be in column, because there are no shrouds from deck to hounds so its much more solid than a pointy headed one. The forestay is opposed by the peak halyard and the mainsheet, and the lowers if arranged as swifters are there to stop the masthead waving about in a lumpy sea.

(and the runners if fitted are to provide a handhold when going forward...) /forums/images/graemlins/wink.gif

We're discussing a nice small gaff rigged boat, whose owner will find this picture of me and my boat in an OGA race on the wall in the pub at Waldringfield, so I think I can say I'm not wholly without experience:

PS - Harrumph! /forums/images/graemlins/tongue.gif

 

[laurance]

There is always more say when we are all so opinionated.
I have have just been sorting out the rigging on a 30tf gaff cutter who's mast as not in column and could not be since her forestay, who's lower end is rigged by passing it through a hole the stem head turned back round the bitts and seized, has stretched. This may have just produced a bit more rake but when combined with a masthead section (area above the hounds) that is only supported forward by the peak halyards and mainsheet when the jib is set up for sailing, resulting in a mast with a graceful curve rather like a racing sloop. lovely in its on way but a little out of place on a Plymouth Hooker.
Seems to me there are many ways a mast can be out of column through stay tension issues, isn't that what tuning is all about?
Fine looking vessel you have there by the way.

 

[Kukri]

Oh, certainly!

I suppose we could define our terms - by "in column" I meant straight, with or without rake, but rake will normally be limited by the mast step and partners.

My forestay used to be rigged that way - not a very good plan, as you cant keep paint on the oak stemhead under the wire and the inevitable happens - I replaced it with a shorter one going to a bottlescrew secured at the stemhead on a new galvanised steel fitting 25 years ago - no more trouble.

Your 30 tonner seems to me to have "masthead issues" - I diagnose (without seeing it /forums/images/graemlins/wink.gif) the dreaded "long masthead" with the peak halyard bolts well spaced out. Commonly done by our Victorian forebears but rightly condemned by Worth. The topmast forestay isn't going to help it much, being a light wire to the bowsprit end.