SS rigging screws

[landyhubbard]

More buggeration. Launched the boat yesterday hoping to go out for a first sail, and the yard managed to seize one of the Hasslefors rigging screws on the backstay when releasing it for the crane. I've done this myself in the past so couldn't shout and swear too much, but its a *** nuisance- there're expensive and not widely available. Is there a way of preventing this- I have always believed that you shouldn't use greese or oil on stainless screws- is this right?

 

[Evadne]

Stainless steel threads can "pick up" very easily, especially if there is grit or swarf in the thread. I think this is why grease is often not recommended, it catches grit and stores it for when you want to undo the screw. /forums/images/graemlins/crazy.gif The other way to get them to seize, of course, is to stretch or bend the screw ever so slightly. In that case the bin is the only place for it, sadly.
Personally I undo them and clean them with WD40 every autumn when the mast comes down, and store them in the cabin. Its not an onerous task but after seizing a couple in my first years of ownership, I found the financial incentive overcame my natural lethargy. If you leave the mast up it would be a good idea to clean them and make sure they are free each spring, before you try any adjustments.

 

[fdmarsden]

Tef-gel, a ptfe gel will prevent galling on s/s.

Expensive, stocked by Harken in Lymington, but so are bottlescrews, coupled with the possibility that standing rigging might need replacing.

www.tefgel.com

 

[NPMR]

When we had a bottle-screw fail last year, the rigger refused to put stainless back on and insisted on bronze/stainless ones(They were pure bronze before).

More costly but as he said "They won't bind and will last far longer" And for the relatively small extra cost, we felt it was a reasonable investment.

It just feels, to me, that I want that pole sticking up, where we want it, with no worries, so I go for peace-of-mind when I can.

 

[Topcat47]

DAG40 is the stuff to put on satinless threads if anything. If it's good enough for the Nuclear Industry, it's good enough for us.

 

[Graham_Wright]

Copperslip

 

[Birdseye]

When we supplied stainless steel wire for cold heading into bolts, we used to either copper plate the wire or coat it in moly disulphide because stainless is quite bad at galling and even welding itself to other steels under pressure. So when I have replaced my own bottle screws I have gone for stalok ones made from bronze.

If you have existing stainless bottle screws, then something like coppaslip should help.

 

[landyhubbard]

Thanks to all who responded to this post. i have also spoken to those nice peeps at Victory Marine who supply Hasslefors products, who rekoned that after at least 25 years the stainless screws would be getting toward the end of their useful life and progressively more prone to galling.and so I have decided to re-equip with bronze bodies as I go, starting with the backstay and the cap shrouds. I will buy a tin of Copaslip for the lowers 'till I get round to replacing them. In fact, the bronze body Haslefors screws are a bit cheaper than the stainless ones, so that helps. Anyone know where I can buy a tin of Copaslip in the Croydon/Bromley area?