Thoughts on converting T-balls to through bolted tangs (1984 38')

[paramita]

I have a 1984 Ericson 38' that I've been scheming to re-rig for a while. One of my outstanding decisions is regarding the Navtec T-balls on the shrouds and. I'm wondering if anyone has replaced their Navtec T-balls with through bolted tangs, or if anyone can point me to a resource for best practice. Mainly I'm wondering if this could be accomplished with out drilling out new holes in the mast and just using the existing T-ball cutouts. And if so should I leave the backing plates in for added support or remove the backing plates in favor of a larger through bolt. Here are my thoughts:


I'm looking at the size of my existing t-ball backing plates, the clevis pins at the bottom of my shrouds, and compression tubes (available from rigrite http://www.rigrite.com/Spars/SparParts/Tangs-complete/Compression_Tubes.htm).


Currently all the pins for my shrouds at the deck are 1/2" or less. All my shrouds have the GIB 740-7 sized backing plate which has a 5/8" wide slot. Rigrite sells a compression tube (K-9632) with 1/2" I.D. and 5/8" O.D.


I'm wondering if there would be any issues simply using a 1/2" through bolt with that compression tube leaving the backing plates? I assumed it would be ideal to leave the backing plates in as it couldn't hurt to have the mast wall reinforced.


Removing the plate would would leave a 7/8" wide cutout which (from looking at Rigrites site) would allow me to use through bolts as large as 3/4".


I've attached a sketch of my proposed plan. Any input would be greatly appreciated.

 

[Ryan L]

Why do all that work to fix something that's not broken?

 

[Guy Stevens]

Or you could go synthetic rigging!

http://www.colligomarine.com/products/colligo-value/mast-connections if you wanted to go with a synthetic rig on the boat.

Taking on the T balls to replace them with classic tangs has advantages and disadvantages. However the correct way to do it is pretty involved here is http://www.yachttech.com/html/Riggingfittings.htm a way to do it correctly if you want to go with SS.

However you could just use T balls again if going with Stainless Steel.

What is driving your want to change?

Guy

 

[Joliba]

Does anyone on this forum know of a rig failure on an Ericson at the ball/mast junction?

 

[paramita]

I'm really not interested in making this project more difficult than it has to be. I was pretty much set on sticking with the T-balls despite hearing about how poorly made the current Navtec Gibb style Tball fittings can be and despite having folks like Brion Toss "strongly encourage" that people not use the Tballs anymore... then I see things like this http://www.cruisersforum.com/forums...g-t-balls-to-through-bolted-tangs-129119.html, which is admittedly just an isolated example, but definitely makes me give this a fourth or fifth thought.

Again, I really just want to get moving on this project, but want to be comfortable taking the boat up and down the west coast. So if it could be as simple as putting some through bolts through the existing holes, I'm all for that. Otherwise, to be honest I probably will end up just sticking with the T balls.

Thanks again.

Matt.