Pin or bolt for double headstay?

Tim R. · Apr 25, 2011

hz293 said:
Some friends and I unstepped my mast on my 1976 Catalina 27 to truck it from Puget Sound to Longview, WA. In the process some pins for the rigging were lost. I was able to get the pins for the shrouds but I'm confused as to what to use for the double headstay. There are 2 holes in the plate and there was still a small bolt attached that had been used for attachment. Of course that went over the side when I tried to use it.

My question is, is the headstay attached to the boat with bolts or pins? What size are they?

Harris

Probably clevis pins. You will need to measure the inside diameter and the seat length to determine the correct pin size. Even if someone here happens to remember the exact size, your boat may have been modified.

What do you mean by double headstay? There should only be 1 wire running from the bow of a cat27 to the top of the mast(or near the top if fractional).

caguy · Apr 25, 2011

Clevis pins are 5/16'' . Pictures would help. Some use a push pin for quick removal. They are pricey and you may want to attach with a lanyard.

RichB · Apr 25, 2011

I notice you mentioned a bolt attaching the forward stay. I assume the mast will stay up all season.
Of course the clevis pin with split ring through the safety hole will be best.
If you do use a bolt again, Be sure to use a grade 5 or 8 stainless American made bolt. Use a bolt with unthreaded shaft in the wear zone (seat length) and a safety hole drilled through the threads. A castle nut and cotter pin will assure you won't have to check it regularly. A hole drilled through the bolt head will allow a safety wire lanyard so it doesn't go overboard.

All that work makes a stainless clevis pin with split ring the easiest solution. Probably on hand at any chandlery.

RichH · Apr 25, 2011

Suggest that you remove one of the 'double headstays' ..... a double headstay creates an absolute variable stress-strain nightmare with respect to stay "sag" .... as the sail thats deployed transfers its load to the stay that is 'bare' and the stay that sail is on 'relaxes' its tension with increasing windstrength !!!!!!!! The result is that the stay WITH the flying sail will be much much too loose (the higher the windstrength the 'looser' the stay becomes and this will cause the jib to greatly sag off to leeward ... causing the boat to 'skid to leeward', the jib to go 'draft aft', the boat will then slow down, cant point worth a damn, and will aggressively heel.
If you need to rapidly change/peel jibs, I strongly suggest that you get a double grooved "Tough Luff" (http://www.tuffluff.com) ... and which rides on a single headstay.

If you keep the double headstays, prepare to apply BODACEOUS backstay tension to get a normal luff shape to a flying jib; but, you must remember that when the rigging goes above 30% tension the useful 'life' of the rigging becomes very 'short' and is then subject to sudden catastrophic fatigue failure.

The sail shape 'problem' that you will get with a double headstay system (sagging headstay, too loose backstay tension) can be found at: http://i1086.photobucket.com/albums/j449/svAquila/MatchingLuffHollow.gif

Use only pins ... bolts are VERY INFERIOR in shear strength when the threads are in contact with the 'bearing surface' and the bolt is used to support 'flexural beam loads' ... a pin is designed and is suitable for such stress connection.

Joe · Apr 26, 2011

hz293 said:
My question is, is the headstay attached to the boat with bolts or pins? What size are they?

Harris

Pins..... use the hole diameter as a guide.

Tim R. · Apr 26, 2011

hz293 said:
Thanks for the info... Tim R, this Catalina 27 is modified with a double headstay so that you can have the next size jib you're going to use already hanked on the second stay or it allows you go wing on wing on 2 headstays. The two stays come down from the mast head and terminate into one headstay plate that's attached to the bow.

Harris

Got it. Thanks. I am so used to having a foil with two sail tape grooves.

RichH · Apr 26, 2011

If you cant remove one of the forestays, totally UNLOAD almost all tension to the 'redundant' stay - leave it 'floppy'. Attach the jib only to the tightly tensioned forestay.

This will cause ALL of the backstay tension to 'react' to a single forestay, and will properly tension that one stay so that it will 'match' the expected sag in the cut of the luff of a jib.

With only one forestay tensioned, you will most probably increase you ability to 'point' and lessen the boat 'skidding off to leeward' when heeled ... and the boat will heel much less at the same windstrength as before. ;-)