Bob Stay Addition

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Vento Solare
Posts: 320
Joined: Wed Dec 31, 1969 8:00 pm
Location: Newport, RI

Bob Stay Addition

Post by Vento Solare »

In accordance with class rule 4.5, approval is requested to allow the use of a Bob Stay during OD racing. The retractable Dynema Bob Stay on the bow sprit is intended to prevent stress on the bow sprit when using a Code 0. This has no impact on deploying or retracting the bow sprit, nor any change in sailing performance when a class legal spinnaker is flown. The bob stay modification is as follows.

1. A single hole 8mm diameter is drilled in the fore/aft in the bow on the centerline approximately 2 inches above the intersection of the anchor locker floor. The outside of the hole has an aluminum Tylaska ring mounted to provide a friction free wear surface that 6mm Dynema line passes through.
2. A 3/8 inch G10 plate approximately 5 inches x 1.5 inches has been bonded inside the bow where the hole was drilled to provide reinforcement for the bob stay stopper
3. A Dynema loop is formed around the outer end of the bow sprit in front of the U Bolt. The 6mm Dynema is approximately 8 feet long and runs through the hole drilled in the bow.
4. The Dynema is terminated inside the bow by tying it to the center of a 1/2 inch stainless rod 3 inches long. This is set so that when the bow sprit is fully extended, the bolt is tight against the G10 plate bonded inside the bow. A loop is provided at the center of the rod to attach a bungee for retrieval.
5. A bungee cord is run inside the anchor locker to automatically retrieve the Dynema inside the anchor locker when the pole is retracted.

Pictures are attached. Should this modification not be allowed for OD racing, it is easily "disabled" by slipping the Dynema loop off the end of the bow sprit and attaching it to one of the bow chocks.

Hole in bow with aluminum Tylaska ring
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G10 Plate bonded inside bow
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Loop around front of bow sprit and path through the bow
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Dynema loop from Bob Stay at front of bow sprit
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Bow sprit extended showing Dynema Bob Stay
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Bow sprit extended with steel rod on Bob Stay against load bearing G10 plate in front of anchor locker
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Bow sprit retracted showing bungee taking slack out of Dynema Bob Stay for storage in anchor locker.
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Wahoo
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Joined: Thu Oct 02, 2014 10:56 am

Re: Bob Stay Addition

Post by Wahoo »

Very Nice! I was thinking of going with a standard bow eye and manually attaching the Dynema when needed. But your set up looks way better. How thick was the bow at the drilling point? How do you keep water from entering the anchor locker?
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Vento Solare
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Location: Newport, RI

Re: Bob Stay Addition

Post by Vento Solare »

The bow is about 1.5" thick where I drilled the hole. The G10 plate was epoxied inside to spread the load so there is no chance that the area would be weakened by the load from the Bob Stay. The Tylaska ring with the Dyneema stops most of the water. Since it is above the waterline, any water that does get in immediately drains through the drain on the stbd side forward in the anchor locker. If the bow is down, the drain in the anchor locker will let water in first, so it really isn't the primary source of water since the entrance hole on the Bob Stay is smaller and restricted by the Dyneema.
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Vento Solare
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Re: Bob Stay Addition

Post by Vento Solare »

To further the discussion, I would propose the following class rules change.

Add to paragraph "4.3 The following are permitted while racing:" the following subparagraph:

4.3.16 A Bob Stay using high-modulus polyethylene fiber (e.g., Dyneema™ or Spectra™) secured in the bow above the waterline and on the Bow Sprit
kerryklingler
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Joined: Fri Aug 21, 2015 9:27 am

Re: Bob Stay Addition

Post by kerryklingler »

Dear J/109 sailors, I think a bob stay is a good idea, especially if you race distance races with a code 0. However there is one consideration that you need to be careful about. If you look hard at the pictures you will realize that there is a ground wire which runs down the stem. This wire is glassed over by the factory when the boat is being made. You need to be careful that in drilling the hole through the stem that the ground wire is not affected, or damaged.

Cheers,

Kerry Klingler
adrianbegley
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Joined: Wed Dec 31, 1969 8:00 pm

Re: Bob Stay Addition

Post by adrianbegley »

I am not convinced by this change. While it is beneficial for distance racing I feel it will encourage boats to add reaching kites to the one-design inventory.

Adrian,
Mad Dogs & Englishmen
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Vento Solare
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Re: Bob Stay Addition

Post by Vento Solare »

Following is input from Jeff Johnstone of J Boats regarding the two proposed changes.

1) In-hauler - this one item would be the best performance value upgrade one could make to the J/109. Having a proper inhaul system (vs. the current method of windward sheeting and having to overcompensate the jib car position aft) would make it easier for the average J/109 team to replicate fast settings and therefore achieve more consistent performance.

2 Bobstay - this was OK'd in the J/111 class as almost all boats had a Code Zero for distance racing which required additional support, so easier for the group to just permit it. There is a slight but tough-to-quantify performance benefit to carrying one on a more powered up reach with the class kite as it minimizes sprit flex which in turn keeps more energy in the sail. A bobstay would also help prolong the life of the sprit and reduce the chances of breaking one during a windy round-up when the kite suddenly refills.
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Vento Solare
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Re: Bob Stay Addition

Post by Vento Solare »

Thanks to all the eligible voters who responded to the survey I emailed. Below is the message sent to the J/109 Executive Board on 27 September 2015:
------------------------------------------------------
J/109 Executive Board,

In accordance with the J/109 Class Constitution, paragraph 7.2 the proposed Bob Stay rule change originally posted on the class forum and discussed at the 9 September J/109 Executive Board meeting is being submitted in writing by the 20 members listed below. It is requested that this rule change be considered at the annual meeting and voted on.

The proposed amendment would add under class rules paragraph "4.3 The following are permitted while racing:" the following subparagraph:

4.3.16 A Bob Stay using high-modulus polyethylene fiber (e.g., Dyneema™ or Spectra™) secured in the bow above the waterline and on the Bow Sprit

The following voting members have approved this submission:
First and Last Name, J/109 Hull Number
Bill Kneller 266
Andrew Berdon 332
Robert Siegel 310
Tom Sitar 258
Reed Bernhard 36
Ed Dailey 205
Scott Sims 124
Bob Schwartz 267
Bill West 89
Hugh Scott Seaholm 142
Jack Forehand 273
Kevin Saedi 361
Alice Leahey 204
Brooke Mastrorio 203
David Christensen 238
Mark Haas 220
tony syme 165
Ronan Harris 153
David Frizell 283
ted herlihy 72
Don Dwyer 244
Michael Canuso 144
Mark Haas 220
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Vento Solare
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Re: Bob Stay Addition

Post by Vento Solare »

The Bob Stay proposal was discussed at the annual meeting on 22 October and voted down by the Executive Board. The good news is that the Executive Board came up with alternative wording that would permit the use of Bob Stays in local events. I feel that the proposed wording is fair for those who want to use a Bob Stay, but preclude its use in nationally sanctioned events so those who don't want to use it don't feel disadvantaged. Thanks very much to the Executive Board for accommodating the desires of those who supported a proposed rules change vote by coming up with revised wording and allowing the class to vote on it.

The updated proposed Bob Stay amendment developed by the Executive Board would add under Class Rules paragraph “4.3 The following are permitted while racing:” the following subparagraph:

4.3.16 A Bob Stay using high –modulus polyethylene fiber (e.g., Dyneema™ or Spectra™) secured in the bow above the waterline and on the Bow Sprit, provided that a Bob Stay may not be used while racing under J/109 one design rules unless specifically permitted by the sailing instructions for the event, or the local Fleet Captain has issued instructions that Bob Stays are allowed for events sanctioned by the local Fleet. Local Fleet Captain instructions do not apply to Class sanctioned events.

Under this proposal, a J/109 owner would be permitted to install a Bob Stay, but would not be permitted to use it in designated Class events such as the North American Championships unless specifically permitted by the sailing instructions for the event. A Bob Stay would be permitted in local Fleet sanctioned events where specifically permitted under the sailing instructions or local Fleet instructions issued by the Fleet Captain. It was noted that where local Fleet Captains issue instructions allowing the use of a Bob Stay for local Fleet racing under PHRF rules, they should advise the local PHRF rating authority of the issuance of that instruction, so that boats sailing with and without a Bob Stay can be appropriately rated.
All current members are being sent an email no later than 13 November 2015 notifying them that the official ballot is available. Voting is available online through noon GMT 13 December 2015, at which time the results will be validated and tallied by the J/109 Class Secretary and announced on the class website. Should the proposed amendment be approved by two-thirds of the votes cast, It will become effective on 1 January 2016.
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