Rigging Screws

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Getting sorted with my new rig design but want to get some oppinions on rigging screws.

Galling - this is reporten to be a problem with all stainless bottle screws but I realised that I have never had, or heard of anyone having a problem. Is this maby a marketing myth to get us to buy mor expensive bronze bodies? or maby something to watch on lightwaight racers etc with overloaded gear?

Fatigue life - Fatigue and fixability are my overriding design criteria, having acceped that there is no way round using rigging screws eccept fitting a gaff rig (bit to radical a solution unless you want one anyway) and that I cant fix these things at sea I want them to last forever and never fail. All the books seem to say they do fail, maby more often than the wire and I am wondering if this is due to fatigue within the thread eventually allowing it to strip. Also what about differences between fabricated and machined ends? Anyone got any imput?

The choice seams to be; Cheap all stainless, carry spare and replace periodically; Broze bodies look better but cost more, body should last for ever as bronze has very low fatigue but are the threads in the s/s ends still a week point therefore still need periodic replacement. All bronze but £80 each, och I need at least ten

Roly, Voya Con Dios, Glasson, Lancaster
 
Stainless ones will gall, BUT if you use a good quality antigall compound they will be fine, cheap ones found in metric threads are ok, in Norway UNF threaded ones are very cheap, for more advice, talk to Warren Scott on Swn Y Mor, in the marina, a mine of wisdom, he also has some wonderful anti gall, I gave it to him!
 
I think that the Merriman pattern are excellent and they are significantly cheaper, albeit fractionally heavier, than certain extremely similar UK made bronze open bodied ones....try classicmarine.com....
 
Any reason why you don't use galvanised ones? they are much cheaper, they don't have the galling problem, and they are actually quite easy to maintain in good order - pack them with grease, and wind self amagamating tape over them once you have them set up.
 
To CCscott49

Are you also at Glasson?

Roly, Voya Con Dios, Glasson, Lancaster
 
Past experience is that galv one rust and jam up but it seams these have been industrial units. Consulted suppliers who say hot dipped marine ones are much better so this does seam a good idea.

The ships pattern fork and ring ones look good as the ring would appear to serve the same function as a toggle and also allow for extending rigging with a length of chain if needed.

The only problem is how to attach then to a modern flat plate chainplate. Needs something like a very narrow throat shackle. Any ideas?

Roly, Voya Con Dios, Glasson, Lancaster
 
You can get apretty big shackle through the ring.

There is some very interesting shackle data on Roger Walker's smack site -
http://www.alberta-ck318.freeswerve.co.uk
taken from an old book by Delmar-Morgan and with some modern s/s shackles included for reference.

The galvanised bottlescrews on my forestay and cap shrouds are 16 years old and are about coming due for replacement now - I may get another two years out of them. Admittedly, the boat has not been in the tropics. but the grease and self-amalgamating tape routine seems to work fine for me.
 
Not in glasson, know it well, warren is my brother, was there with Englander some time ago. Now in Portugal. Galvo ones, connected to stainless will rust like blazes! if you have stainless rigging, if not go for the galvo ones, but marine grade as mentioned.
 
Thanks, that will be another reason I have had bad experiences of galvo rigging screws, they would make good scraficial anodes on a stainless rig. I am fitting 7*7 galvanised wire splices to bronze thimbles so hopfully not a problem though having raised the piont it might be worth insulating them from the s/s chainplates!

I know Swyn-y-mor a lttle as we wher berthed next door this summer, small planet, sailing obviously dosn't run in your family, it gallops. Enjoy the sun down there I will be joining you shortly after finishing this boat and my nursing course.

Enjoy the sun

Roly, Voya Con Dios, Glasson, Lancaster
 
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