There has been some discussion on the
Replacing Spin Halyard thread about the replacement aluminum Jib box assembly offered by Rig Rite to replace the stainless one that is no longer offered. This is the
link to the Rig-Rite page with the information on the sheave box.
I am pasting the text below from the Rig-Rite web page and adding emphasis
(red text) for the class measurer to investigate the impact on
J/30 Class Rules under paragraph 5.8.2
Prohibited Alternatives or Additions, specifically paragraph 5.8.2.1 which states
A headstay length which exceeds 10935 mm when measured from pin to centerline as shown in the following diagram. (See figure 1.)Text from the Rig-Right page is as follows:
(This is new Assembly)Aluminum Jib Box Assembly w/ 3/8" Pin: K-11597-1:Cast aluminum four (4) halyard internal Jib Box Assembly with 3/8" pin and 3/8" Forestay Toggle. Accommodates two spinnaker halyards over two jib halyards, in a trim, narrow and lightweight unit. Features heavy-duty Nylatron Sheaves: (2) 2" Sheaves for Spinnaker Halyards,
K-11594; (1) 2" Sheave for Upper Jib Halyard,
K-11640; (1) 1 3/4" Sheave for Lower Jib Halyard,
K-11639; and (2) 5/8" secondary Sheaves (forward) for the 2 Upper Halyards,
K-11585. Jib Halyard Sheaves are suitable for use with wire or rope halyards. All Sheaves are 1/2" wide for snag free handling of halyards up to 3/8" diameter. Assembly fits in mast cutout 9 3/4" high x 1" wide, and fastens with (4) 1/4"-20 machine screws (included). Internal mounting flange is slightly curved to fit a variety of masts. Assembly is designed to fit through the mounting slot and is then fastened from the outside. Forged Chrome Bronze Toggle,
Mer 5770-412, is included. Unit measures 12 7/8" long x 1" wide and projects 2" (maximum) inside of mast. Suitable for use with a variety of mast sections on boats with forestays up to 1/4" dia.
As used on J/30, J/29F, and others. A2-4, 4-5
(This is old Assembly)SS Jib Box Assembly w/ 3/8" or 1/2" Pin: K-10658**D:Welded SS four (4) halyard internal Jib Box Assembly with 3/8", or 1/2" pin for Forestay Toggle. Accommodates two spinnaker halyards over two jib halyards. This heavy Jib Box was used on a variety of MORC boats including many of the J/30's and J/29F's. Assembly fits in mast cutout 9 3/8" high x 13/16" wide, and projects 2" inside of mast. Mounting flange is fastened to the Mast with (12) 1/4" fasteners.
This part is discontinued, having been replaced by the much lighter
K-11597-1, above. A sheave and bushing replacement kit,
K-10658SK, is available, see below.
Please note: When replacing this item with the new
K-11597-1 (the mast cutout needs to be widened and extended downward),
the Forestay pin will be 1" higher on the mast; the forestay length will change accordingly. A7-4
I believe that there may be a change to the class rules for allowable headstay length so the mast is in a consistent position intended by the class rules, dependent on the type of jib box installed. Class measurer, please take for action and report your findings. Class feel free to discuss your comments on this topic in this thread.