Measurers Corner

Measurer’s Interpretations and Recommendations

Topic:Mast
Question:Would it be legal to use Tball shroud terminals in lieu of marine eyes on the mast?
ID Number:000022
Date:2008-09-22
Short Answer:No 
Answer:The following interpretation is proposed: The headstay and upper and lower shrouds shall connect to the mast using marine eyes to through-bolted tangs.  
Section:§IV 5.9 
Image:
Status:Affirmed
Action Date: 
Fri Nov 15 05:07:11 2019
DateNameComment
2008-09-22Richard RobbinsSee http://www.navtec.net for details.
2008-09-23Richard Robbins5.9 Standing Rigging Standing Rigging shall be of the types and sizes shown on Official Plans 1 and 2 and shall be fastened to the mast and hull only where shown in the Plans and only in the manner provided for in the Plans and in these Specifications. Use of "Sta-Master" brand turnbuckles has been ruled by the class to be prohibited.
2008-09-23Bam MillerThe t-ball fitting has been around for 25 plus years and is an excellent retro fit for existing and new spars because of its ease of installation and it ability to perfectly align to a load in a huge range of directions. It also allows the complete retrofit of an entire stay, including mast tangs and cross bar, which should be replaced when the old rigging wire is retired for new. While the blue book doesnt specifically allow them, it also doesn't specify what manner of attachment to the mast the shrouds currently have. It should be pointed out that similarly, both in terms of holding the mast up and different executions resulting in the same solution; the design of the side shroud chain plates on the deck have gone through a number of design changes that neither weakens or strengthen the wires they support. The T-balls offer no greater or weaker structural solution (as is the case with the sta-masters). It should also be pointed out that other ISAF classes, including the J-24, have changed the termination from Marine Eyes to T-balls on their shrouds without need for accommodation in their class rules. Bam Miller
2008-11-19Richard RobbinsUppersLowersMarine eye
2008-12-05Richard RobbinsOn December 4, 2008 the following addition to §IV 5.9 was affirmed by the Governing Board: The headstay and upper and lower shrouds shall connect to the mast using marine eyes to through-bolted tangs.