New Standing Rigging - Wire Size?

[bwalsh]

I am in the process of wrapping up a complete refit of a sabre 28. Boat included a whole gut job, mostly all new structural bulkheads and stringers etc. Lots of glass work as well as fancy new (read "overpriced") wood work and paint too. The boat is nearing launch and Ive fabricated all new chain plates but am left with the same old rigging. Time for a replacement but which wire? Heres the issue: I have kept the clevis pin holes in the chainplates the same 3/8" size. This matches all the sizes on mast tangs too. My original wire is 7/32 but I cannot get swages from anywhere for new 7/32 wire to fit any of the 3/8 existing conditions. Do I go down to 3/16 wire or do I go up to 1/4"?? both allow 3/8 forks and eyes. I understand the "bigger is better" and "if stuck in a blow" peace of mind idea, but in my trade we overbuild everything to the point that it is unnecessary at times. Id rather not overbuild and add extra weight. Is going to 1/4" overbuilding? Will new 3/16 be suitable? I understand the basic dynamics of rig loading and can see advantages to both ideas but am looking for some fellow sailor insight. All ideas on such matters helpful. I know you've all been in these shoes wracking your brains about your boats and i need food for thought! Thanks in advance!

[Pblais]

I understand the "bigger is better" and "if stuck in a blow" peace of mind idea, but in my trade we overbuild everything to the point that it is unnecessary at times.

Overbuilt wire alone won't save you. There is every single other part of the boat that has to match. Over building just one element is money down a rat hole and a poor excuse for a design. If you had to step up the wire to save some money it does not come with great assurance. Every other part of the rigging would fail first. In the end if the worst happens it is one thing that fails, not all the parts at the same time.

So if you can't get the design spec smaller sized wire you then get the bigger size. Just so know you added more weight aloft and didn't effectively make the rig stronger. You know if you go smaller then you are are on your own. The rig won't know how hard you tried or could not complete the job properly. You got this far and I think the answer is more a matter of how well you did along the way.

You can't redesign a boat one part at a time asking the forum to help you decide only on the basis of wire size and your ability to get or not get one size wire. How good a job did you do on the stringers and bulkhead. I would say the level of quality should be consistent.

[Ex-Calif]

Originally Posted by bwalsh

Heres the issue: I have kept the clevis pin holes in the chainplates the same 3/8" size. This matches all the sizes on mast tangs too. My original wire is 7/32 but I cannot get swages from anywhere for new 7/32 wire to fit any of the 3/8 existing conditions. Do I go down to 3/16 wire or do I go up to 1/4"??

If you don't want to do the load analysis you go up a size.

I wouldn't reduce size unless I had the numbers.

[Jmolan]

Originally Posted by bwalsh

I am in the process of wrapping up a complete refit of a sabre 28. Boat included a whole gut job, mostly all new structural bulkheads and stringers etc. Lots of glass work as well as fancy new (read "overpriced") wood work and paint too. The boat is nearing launch and Ive fabricated all new chain plates but am left with the same old rigging. Time for a replacement but which wire? Heres the issue: I have kept the clevis pin holes in the chainplates the same 3/8" size. This matches all the sizes on mast tangs too. My original wire is 7/32 but I cannot get swages from anywhere for new 7/32 wire to fit any of the 3/8 existing conditions. Do I go down to 3/16 wire or do I go up to 1/4"?? both allow 3/8 forks and eyes. I understand the "bigger is better" and "if stuck in a blow" peace of mind idea, but in my trade we overbuild everything to the point that it is unnecessary at times. Id rather not overbuild and add extra weight. Is going to 1/4" overbuilding? Will new 3/16 be suitable? I understand the basic dynamics of rig loading and can see advantages to both ideas but am looking for some fellow sailor insight. All ideas on such matters helpful. I know you've all been in these shoes wracking your brains about your boats and i need food for thought! Thanks in advance!

You should toss the wire and go to Dynex Dux. You can splice it yourself and probably come in at less of a cost that SS, be twice as strong, and loose a bunch of weight up high.

Check out Home

Check my other threads on Synthetics. Lot of info there....Wire is dead.

[s/v Jedi]

One method to get away with 3/16" is to use dyform wire if available in that size. Just compare it's strength with 7/32" regular wire. If it's as strong (I think it will be) you can use that. Another way of looking at this is to check the weight of the wire per 100' or whatever they specify it. You want at least the same weight as the original 7/32" original wire (dyform weighs more than regular 1x19 as it's strands aren't round so it's more compact wire).

Check if you need special swage fittings for it. If you use Norseman (or alike) fittings, you need the dyform cones instead of regular but the fittings are the same.

This trick allowed us to go from regular 1/2" wire (12.7mm) to dyform 12mm.

cheers,
Nick.

[daedaluscan]

I'd recommend speaking to the guys t rigging only.

They know there stuff.

[cal40john]

I don't know if you're supposed to use them together, but here's a turnbuckle with a 3/8th pin, that has the correct thread to attach to a
swage stud for 7/32nds wire, all made by the same company.

John



01181 ARC TS-0012128,900 lbs. 3⁄8" 3⁄8-24

Fisheries Supply


01175 ARC SS-7-387-3⁄8" 3⁄8" - 24 RH 7⁄32"


Fisheries Supply

[cal40john]

Originally Posted by s/v Jedi

One method to get away with 3/16" is to use dyform wire if available in that size. Just compare it's strength with 7/32" regular wire. If it's as strong (I think it will be) you can use that. Another way of looking at this is to check the weight of the wire per 100' or whatever they specify it. You want at least the same weight as the original 7/32" original wire (dyform weighs more than regular 1x19 as it's strands aren't round so it's more compact wire).

Check if you need special swage fittings for it. If you use Norseman (or alike) fittings, you need the dyform cones instead of regular but the fittings are the same.

This trick allowed us to go from regular 1/2" wire (12.7mm) to dyform 12mm.

cheers,
Nick.

I thought I read somewhere dyform is no longer being made. All the companies selling it are saying discontinued.

John

[Randy]

What fittings are you using?

Norseman, Stayloc? Or be adventurous & do the DUX. Don't go cheap with swagged. You've got a 28' monohull, I can't imagine 3/16" won't work.

90% of the time failure is at the fitting. When in doubt call a rigger throw him 50 -100 and sleep at night -- err not if you're sailing through the night!

[roverhi]

dyform is supposedly no longer being made so what you'll find will be remnants. May have to go to a lot of different sources to get what yhou need. Doubt that Dyform is the solution in any case. Dyform is not much, if any stronger than 1x19 in the smaller sizes. IIRC, you have to go larger than 1/4" to get real increase in strength over comparably sized regular wire. Also, Dyform is heavier per length. It gets it's strength because it has more metal per foot.

Have you tried Norseman or StaLok terminals?? They had some odd pin sizes when I first started using them. You can do the rigging yourself and make up the additional cost by not having to hire outside labor. They also are a lot better than Swages IMHO.

Aloha
Peter O.
Pearson 35

[GordMay]

Originally Posted by roverhi

dyform is supposedly no longer being made ...

Bridon is no longer making Dyform, or Navtec is no longer distributing it?

[s/v Jedi]

Hmm.. indeed. The only reason I can see for Dyform disappearing is that people choose fiber now? I'm puzzled.

ciao!
Nick.

[Pblais]

Hmm.. indeed. The only reason I can see for Dyform disappearing is that people choose fiber now? I'm puzzled.

The companies that make it also make steel cable. It is no surprise that they don't make much stainless cable. They only make it when there is a market and the demand is up. Old boats don't drive the market, it is the new boats that do.
I think DIX is a great new thing and the technology is clearly there to make it a great alternative if not the only one. There is no great rush to fiber all of a sudden. There are too many older boats not re rigging even if they should. Neglect drives more motives than anything else. If it ain't broke.

[bwalsh]

Thanks everyone so far!

Ive researched the dux and see that it requires larger sized pins than i can accomodate. Im hoping to stick with the regular old 1x19 as dyform does seem to be out and cost effectively, how can you go wrong with the same (now old) technology they built this old baby with?!

Another thought i had was to use 304 stainless wire vs the 316 I have now based on its higher break strength. The boat is only in the water three months a year.

Ive been informed on sailnet that there is one company (Ronstan) that still makes the proper size swages to fit my 3/8 chainplates and tangs. The sta lok, norseman and also suncor mechanicals were all larger as well, none for 7/32" wire that have 3/8 eyes or forks. More like 7/16". I would really like to use the mechanical fittings if they would only fit! I was almost dead set on 304 stainless Loos and Co with sta loks to match, until i found out the ronstan secret. Now I just hope they have a good customer service dept... because this guy is about to phone call em up!

From all this im seeing that there is no real easy calculation for needed wire sizes. Just lots of old rules of thumb etc. On my sail back with the boat after purchase we experienced moderate 10-20 knot winds and made 230 miles straight only to discover the rotted bulkhead a week after our arrival. There wasnt a quarter inch of viable wood left and im guessing it wouldnt support a load of even 150 lbs nevermind the thousands that the rig is guesstimated to be experiencing. Well now the boat is back to newish condition with 3/4 ply bulkheads epoxied into place and will support any load i can put on it. But is my lesson here that the rest of the rig is way overbuilt>? Ideas? Anyone know who or how or where to find the info to calculate rig loading? This is a great education anyways... Thanks again guys.

[roverhi]

I looked up the eye sizes for Norseman's and they showed 3/8" and 7/16" pin size for 7/32 wire. Look further and you'll find someone who stocks it or can get that size for your.

304 is okay if you stay up north and don't mind it bleeding a bit. 304 in warm water bleeds rust and pits in a short period of time. Personally, I'd only use 316 but then the weather is pretty nice around here all the time.

Aloha
Peter O
Pearson 35