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svcattales · 22-11-2009, 18:15

I was trying to free up the turnbuckle on one of my upper shrouds and broke the threaded stud that goes into the bottom of the turnbuckle. The broken stud surprised me in that it comes in two pieces. The bottom half which connects to a the chainplate via a toggle has a 3/8" threaded stud that screws into the top half. After the halves are screwed together, the outside of the stud was welded and polished. The weld broke, but not the stud. The stud itself is 3/4"diameter.

Is this a common construction practice and does it have the same strength as the rest of the stay? At first I thought this was a "Rube Goldberg fix", but after careful examination it was really designed that way. See pics:

**roverhi** · 22-11-2009, 20:17

Is this a Taiwan built boat??? Looks like typical construction where labor is cheap.

s/v 'Faith' · 22-11-2009, 20:29

Wow,

I can understand why they might make the part this way, from a production standpoint.... It probably tests out well WRT load testing...

But I do not believe I would want something like this on my boat.

Of course that is much easier decision for me to type that, then for someone else to decide to replace a bunch of turnbuckles....

Good luck in whatever you decide to do.

rustypirate · 22-11-2009, 21:35

This looks like it may also be a repair from a previous break.

Possibly someone unwilling or unable to pay for a new fitting.

SkiprJohn · 22-11-2009, 23:47

Never saw anything like it. Once the weld breaks there is only 3/8" stud holding what should be held by 3/4" not near as much metal there. Time for a new piece.
regards

Joli · 23-11-2009, 02:27

Uh Oh, tha't not right. Time to call the rigger. There is no way to pin that to stop it from spinning.

Talbot · 23-11-2009, 02:48

Check the others and replace as well.

cooper · 23-11-2009, 02:52

I dont know of any rigging screws that do that !! It defeats the purpose of the material size. Throw away/get another...and definately check your others,.....
I cant even imagine why you would do that !

svcattales · 23-11-2009, 05:00

Quote:

Originally Posted by rustypirate

This looks like it may also be a repair from a previous break.

Possibly someone unwilling or unable to pay for a new fitting.

That was my initial thought, but when you look at the toggle for the eye the slot is not wide enough for the 3/4" stud. If the stud was one piece, the only way to do it would be to put the eye through the slot and then press in the pin. I don't know how the pins are installed, but I suspect either a machine press or heating the eye and cooling the pin. Does anyone know how that is done?

I sent the stud to a rigger and asked for a one piece replacement, but I don't know if I have the same design on the other upper shroud. It would be really nice to know if this design was done on purpose or whether one side was "fixed by Captain Ron."

gonesail · 23-11-2009, 05:10

good lord that looks like an achilles heel waiting to fail.

svcattales · 23-11-2009, 18:45

Quote:

Originally Posted by SkiprJohn

Never saw anything like it. Once the weld breaks there is only 3/8" stud holding what should be held by 3/4" not near as much metal there. Time for a new piece.
regards

Yeah your're right. I got a call from the rigger and this was definitely a "Captain Ron fix." It was so well hidden it clouded my common sense. Cat Tales was in charter for several years and I thought I had found all the jury rigged stuff already, but I guess not.

I'm going to replace both upper shrouds even though there is no sign of a weld on the other side. The rest of the rig looks good and just got a good report from a surveyor.

rustypirate · 23-11-2009, 18:56

As for that pivot pin, it is not that hard to heat an eye, then press in a pin with a hydraulic press, then cool the eye.

The pin will never move unless the eye is re-heated.

Joli · 23-11-2009, 18:57

Glad you found that prior to a mishap. Gotta love some of the "re-engineering" that takes place just to save a buck. Penny wise and pound foolish.

The method of manufacure for a screw like that is headed from rod and then machine the body then roll the threads.

svcattales · 24-11-2009, 14:37

Quote:

Originally Posted by Joli

Glad you found that prior to a mishap. Gotta love some of the "re-engineering" that takes place just to save a buck. Penny wise and pound foolish.

The method of manufacure for a screw like that is headed from rod and then machine the body then roll the threads.

I guess I should be happy for finding this problem. I had a rigger look at the rest of the rig and found some cracked swages on uppers, lowers and "diamonds." We are going to rerig everything. Although this wasn't planned or in the budget, it sure beats yelling "timber" on our next cruise.