Strengthening Sprit Retrieval Attachment on Bulkhead

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Vento Solare
Posts: 394
Joined: Wed Dec 31, 1969 8:00 pm
Location: Newport, RI

Strengthening Sprit Retrieval Attachment on Bulkhead

Post by Vento Solare »

One of my crew was sailing in a double handed race on J/109 Strider in May. They ended up having to retire early due to a broach that rounded them up with the sprit extended. This put significant load on the sprit retrieval line causing the attachment padeye to pull out of the forward bulkhead in the v-berth. It ended up doing significant damage to the bulkhead.

Damage to Strider's Bulkhead
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I have been concerned about the same potential damage on Vento Solare and decided to come up with a fix to prevent similar damage from happening. The fix is as follows:

1. Remove the existing sprit retrieval line padeye attached with #10 machine screws inside the v-berth on the forward bulkhead and drill new holes for a larger padeye using 1/4-20 hex bolts. I used one of the existing holes and enlarged it. The other existing hole was hidden under the new padeye and a 2nd hole drilled to match the padeye.
2. Place a 1/8" G10 plate that is approximately 4" tall and 6" wide, contoured to fit around the curvature of the sprit housing and drilled to match the bolt pattern of the new padeye. I made a paper tracing once the holes were drilled in the bulkhead, then transferred this to the G10 which was cut with a scroll saw.
3. The G10 plate was bonded on the bulkhead inside the anchor locker using 4200. The padeyes were attached and the 1/4-20 hex bolts tightened to squeeze the 4200 out the edges, with residual cleaned up using acetone rags.
4. A Wichard 6361 forged eye nut was screwed on the second bolt down on the stem head fitting inside the anchor locker. There was sufficient thread engagement so the existing bolt did not have to be replaced.
5. Amsteel 5/16" line was tied to the eye bolt and the other end attached to a turnbuckle. The far side of the turnbuckle attaches to the new padeye inside the anchor locker.
6. The turnbuckle is tensioned so it is "tight" resulting in any load from the sprit retrieval padeye being transferred to the stem head fitting.

Oversized Padeye with 1/4"-20 attachment hardware
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G10 Plate, Padeye and Turnbuckle Attachment Inside Anchor Locker
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Wichard 6361 Eye nut attached to existing stem head fastener
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View looking into anchor locker shows completed bulkhead strengthening on right, and bob stay retrieved with bungee cord on left
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Charlie
Posts: 1
Joined: Wed Apr 13, 2016 4:41 pm

Re: Strengthening Sprit Retrieval Attachment on Bulkhead

Post by Charlie »

Rhapsody, thanks. I noticed you installed a bobstay. Did you drill the hole athwartships or directly into the bow? It would be great to see some pictures and read your comments on the installation and how it works.

Thanks.


Charlie
#59, Lake Superior
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Vento Solare
Posts: 394
Joined: Wed Dec 31, 1969 8:00 pm
Location: Newport, RI

Re: Strengthening Sprit Retrieval Attachment on Bulkhead

Post by Vento Solare »

I drilled through the bow. Pictures are in this forum post.
Mvallus
Posts: 44
Joined: Mon Sep 22, 2014 9:40 pm
Location: Michigan

Re: Strengthening Sprit Retrieval Attachment on Bulkhead

Post by Mvallus »

Bill,
I will be performing this modification over the winter...Do you recall the size of the new pad-eye you used? Just wanted to order the parts without making a trip to the boat. Thanks, Matt
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