Re-rig Cape Dory 25D

[Amgine]

I'm taking the dive and beginning a complete replacement of all standing rigging, a new furler, for my Cape Dory 25D. I'm somewhat torn between doing it myself, or having it done by a rigger (since none of the three rigging shops I left messages at have returned my call in a bit more than a week, I'm leaning toward do-it-myself.)

The plan is to use the spec in the manual for length, bump up the wire one size from what is currently there and going with 316. Fittings would be navtec Norseman. And here is where the difficulties begin: measurements and details.

The current wire size for the lowers should be 5/32. The clevis pin at the tang is 1/4. Navtec's fittings have a 1/4 eye for 1/8. If I bump the wire up to 3/16, the eye would require a minimum of 5/16 clevis (two sizes larger.) Even staying in the same size wire would require the 5/16 clevis as the Norseman is not available with a 9/32 eye. The tang would require minor machining or replacement, I think, to accomodate the increase in clevis size. Of course the concern is that such machining might reduce the strength of the tang below that of the wire or clevis, making it the first thing to fail and a jury-rig at sea more difficult if not impossible...

I haven't started measuring the uppers and stays (mast is up at the moment) but I'm sure I'll find similar issues there. I know I'm probably over-thinking this, but has anyone re-rigged a 25D?

[barfwinkle]

First I would not machine the tang!

I have been looking at this myself and I have looked at norseman, hayn Marine and one other that escapes me at the present.

I have yet to find a vendor that has products that will fit the lower in the next size up. I.E. the lower shroud tangs will not take anything larger than a 5-16s pin. I haven't looked at this in the last few weeks but that is how I recall the situation.

I do know that Mike Hunter aboard s/v Breezy up sized his lowers, but also as I recall was unable to do the same with his uppers! As I recall the largest hole diameter on the chain plates is 5/16 and most of the DYI products have 3/8" for a pin hole.

Now that I think about it for a bit, I dont really recall the other products as I want to use Hayn Marine's HiMod stuff for ease, and they do not have 5/16s pin holes. The others may. I have not looked at "Quik Connect" (or something like that) in a while. Give them a look.

Fair winds

[rtbates]

I haven't addressed this issue with Seraph, yet. But what would happen if you used a 1/4 pin with the 5/16 eye? There would be 1/16 slop, and the 1/4 pin would be weaker than a 3/8 (how much, the weak link?) Once the rig was tensioned would it be a problem? Would you expect the slop to cause the rig to pump as it loads and unloads?

[bottomscraper]

I haven't addressed this issue with Seraph, yet. But what would happen if you used a 1/4 pin with the 5/16 eye? There would be 1/16 slop, and the 1/4 pin would be weaker than a 3/8 (how much, the weak link?) Once the rig was tensioned would it be a problem? Would you expect the slop to cause the rig to pump as it loads and unloads?

I think this is a not a great idea. I ran into a similar problem on our previous boat. The original chain plates had larger holes than the pin size of the fittings. I posted a question on the Brion Toss web site and was told that it was a very, very bad thing. In that case it was a bit easier since I could find fittings with larger size pins.

Note that Sta-Lok does make a fork with 5/32" wire and a 1/4" pin but it is not a toggle fork. You could add a separate toggle. What about the other end? What size are the holes in the chain plates / turnbuckle threads?

Maybe your best bet is sticking with the 5/32" wire and swage fittings, I think you will find a larger selection for swage fittings.

[Amgine]

The reason for not using the smaller clevis in the larger hole is the reduced load-bearing surface; there's just less metal taking the load at the tang, so you increase force at that point. One size up or down might be doable, but bad practice. Two sizes probably not. It also allows for greater twisting motions before transfering the load to the tang.

The actual sheer strength of the pin is probably not going to be the problem. It's much more likely to be the tang as the weakest point in the system, and at the same time increasing the point loads there.

I'm still generally opposed to swaged fittings due to the unrepairability, but I may look into the possibilities. Either that or start calling riggers again.

Amgine

[rtbates]

I haven't addressed this issue with Seraph, yet. But what would happen if you used a 1/4 pin with the 5/16 eye? There would be 1/16 slop, and the 1/4 pin would be weaker than a 3/8 (how much, the weak link?) Once the rig was tensioned would it be a problem? Would you expect the slop to cause the rig to pump as it loads and unloads?

I think this is a not a great idea. I ran into a similar problem on our previous boat. The original chain plates had larger holes than the pin size of the fittings. I posted a question on the Brion Toss web site and was told that it was a very, very bad thing. In that case it was a bit easier since I could find fittings with larger size pins.

Note that Sta-Lok does make a fork with 5/32" wire and a 1/4" pin but it is not a toggle fork. You could add a separate toggle. What about the other end? What size are the holes in the chain plates / turnbuckle threads?

Maybe your best bet is sticking with the 5/32" wire and swage fittings, I think you will find a larger selection for swage fittings.

Rich:

Thanks for the info.

[Dave Brandt]

I have a CD-25 ( not D ), but the size of the rigging is the same. When I replaced my standing rigging I used Rigging Only and have nothing but good things to say about them, great people to work with.

On recommendation of Rigging Only, I up sized the lowers to 3/16" because all the deck fittings on my boat had 3/8" holes and the 5/32" wire could use a max. of 1/4" pins. They said it is really not a good thing to have mismatched pins and fittings.

I had the top fittings swaged on and I used Sta-Locs on the lower fittings. Worked great, easy to install.

I would give the guys at Rigging Only a call.

Dave

[car1260]

We just replaced the standing rigging on our 25D. We planned on doing it ourselves, but after having a rigger who has completed the Whitby round the world race tell us that swages are the way to go(and cheaper too) we hired a rigger to do it for us. Call Greg Knightson at Quantum Sails at 941-365-7245 and he will tell you how he rigged our boat. He only recommended going up one size on the lower shrouds, so now all the rigging is 3/16. Going larger on the upper shrouds and stays will only add weight aloft that you do not want on such a tall rig for boat length. Greg is a respected cruiser/racer in Southwest Florida & an all around great guy. He also built us a 135 reefing genny for our roller furler that is superb. Mechanical fittings are great for spares, but experienced riggers we have spoke with have never seen a swage fitting fail, only the wire inside it! It cost us $1184 for everything including new 3/16 shrouds, new 3/16 stays, new turnbuckles, new 3/16 lifelines, pelican hooks, even a retune in 6 months.

[Amgine]

Well, I went through Brion Toss's rigging survey class... I've now seen several swages which have failed.

Then we went down to the harbour to examine rigging from the dock, and found a couple more swages which were in the process of failing. Radial cracking and even chunks of material missing. It was a *very* informative class.

After coming back to the boat and re-examining everything, my rig isn't in as bad a shape as would be expected for its age. But it's still not safe. It is well beyond the predictable lifespan for stainless wire (23 years old). And there is evidence of over-stressing related to stepping the mast (a kinked lower, a bent lower stud on a turnbuckle.)

Dave Brandt: Thanks for mentioning the chain plate attachments! I had not noticed they were 3/8"; now I have to run down and check mine. If you upgraded in size, what did you do about the mast tangs? Did you replace/upgrade them, or mill them to 3/8", or were they over-sized with too small pins to begin with like the deck?

[Dave Brandt]

I drilled out the mast tangs, they were oversize and there was plenty of metal to work with.

Dave

[Dick Kobayashi]

I don't know the condition of your boat or where you plan to sail. But when I bought my 25D 5 years ago. I replaced the fore stay right away - at the same time I put on a furler. Then the next year I replaced the backstay and so on. You only have one forestay and one backstay - hence the priority. Also there is not any evidence of problems with the sidestays so I haven't replaced them yet. My main point is that this is a job that can be performed incrementally, if conditions warrant. I am not sure about the rationale for wire size increases, but then I don't know your situation.[/i]

[Amgine]

The boat is in good condition, except for everything I'm doing to the poor thing to upgrade systems. The big goals before July 1 are all new rigging, and sails.

I'm having second thoughts as it comes time to plump down big bucks on the sails, but the rig needs to be something I feel I can repair/inspect, even if the reality is something different.

I've run the numbers and, as we all expect, the standing rigging specification from Mr Alberg is robust and very heavy. My boat did not come with his specification, but wire a size smaller all around. And even that is still a margin of safety of more than 4:1, at least. Skene's and Toss agree that the maximum load on the rig would be approximately 3000 lbs, using a safety factor of 2.5.

With that number, lowers could be 3/32" and uppers/stays 1/8" and still end up with 4,000 per side, a safety factor of more than 3:1. I'm hoping, instead, to go with smaller dyform wire if I can find it, 4mm for lowers and 5mm for uppers.