1984 Nacra 5.7 Chainplate :: Catamaran Sailboats at TheBeachcats.com

1984 Nacra 5.7 Chainplate

stufish

Rank: Lubber

Registered: Jul 02, 2021

Last visit: Aug 06, 2021

Posts: 11
Posted: Aug 02, 2021 - 05:46 PM

So... I bought a "project" and realized that it has a broken port hull chainplate for the jib. I contacted Murray Sports to purchase one, and was told that they don't make it anymore. Groan. So where would I scavenge one? (I'm trying to upload image and can't).
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Aug 02, 2021 - 07:15 PM

Make an album for your project. Upload the photos to that album, then you can paste them into your posts.
How to is in the FAQ .

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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
tominpa

Rank: Mate

Registered: Jul 29, 2015

Last visit: Apr 23, 2024

Posts: 577
Posted: Aug 03, 2021 - 10:10 AM

The forestay bridle chainplates are accessible and repairable by opening the top-deck at the bow. The part you need is here: https://www.h2o-sensation…-vorm-2000000001951.html This thread discusses the same failure in a N 5.5. https://www.thebeachcats.…ms/viewtopic/topic/18322

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Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
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stufish

Rank: Lubber

Registered: Jul 02, 2021

Last visit: Aug 06, 2021

Posts: 11
Posted: Aug 03, 2021 - 01:26 PM

Heres the problem:

tominpa, I don't think that chainplate is the same. The bend is different.

Edited by stufish on Aug 03, 2021 - 01:43 PM.
MN3

Rank: Master Chief

Registered: Jun 20, 2006

Last visit: Apr 06, 2024

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Posted: Aug 03, 2021 - 04:34 PM

Quotetominpa, I don't think that chainplate is the same. The bend is different.

I have redone 4 bow tangs and side stays in my days
the upward bend is done by hand to the tang (chainplate), at least on my cat (mystere)

Mine were very different style and i had them fabricated by a spar welder

Edited by MN3 on Aug 03, 2021 - 04:38 PM.
MN3

Rank: Master Chief

Registered: Jun 20, 2006

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Posted: Aug 03, 2021 - 04:39 PM

It looks like you have a secod attachment bow tang on the outside of the hull? is that correct?
stufish

Rank: Lubber

Registered: Jul 02, 2021

Last visit: Aug 06, 2021

Posts: 11
Posted: Aug 04, 2021 - 04:59 PM

Yes. TBH, I'm not even sure of the rigging. Anyone have a detailed picture of the way it's supposed to be rigged? I've never rigged much less sailed a Nacra yet
stufish

Rank: Lubber

Registered: Jul 02, 2021

Last visit: Aug 06, 2021

Posts: 11
Posted: Aug 04, 2021 - 05:26 PM

MN3It looks like you have a secod attachment bow tang on the outside of the hull? is that correct?

MN3, so I've managed to look at the rigging on some other Nacra 5.7. So I guess somewhere the previous owner broke the chainplate, then instead of fixing it, just put the 2nd bow tang on each hull instead. Hmm.
tominpa

Rank: Mate

Registered: Jul 29, 2015

Last visit: Apr 23, 2024

Posts: 577
Posted: Aug 04, 2021 - 08:39 PM

My 5.7 only has the inboard bow tang on both sides with a single hole that attaches to a bridle wire and connects to a 1/2 twist shackle then to a chainplate like the one in your image attached to the outside of the hull. Someone really modified your boat! Let me know if you want some close-up images of this forestay rig, but your port hull is correct except the bridle should connect to that inboard tang, not the chainplate, the starboard, not so much.

Edited by tominpa on Aug 04, 2021 - 09:44 PM.

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Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
--
tominpa

Rank: Mate

Registered: Jul 29, 2015

Last visit: Apr 23, 2024

Posts: 577
Posted: Aug 04, 2021 - 08:49 PM

MN3, I have not had to repair the bridle wire tangs on my boat, so I don't know exactly what to expect if I open the top, but that would tell the tale. The images in your post are not even close to what I see on mine.

--
Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
--
MN3

Rank: Master Chief

Registered: Jun 20, 2006

Last visit: Apr 06, 2024

Posts: 7088
Posted: Aug 04, 2021 - 09:31 PM

Quote but that would tell the tale. The images in your post are not even close to what I see on mine.

not sure what you mean "that would be the tell tale"

as per the images not being close to what you see - do you mean the style of the bow tang itself?

Mystere's use something like this but it has no kink and my welder added a SS bar at the correct spot
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Aug 05, 2021 - 09:04 AM

Tom is correct, you should only have a single hole, in a small tang, on the INBOARD side of the bow,
If the age of the rigging is unknown, I would have a new set of wires made.
Spend the extra few $ & have them made with marine forks on one end. Then you simply pin the fork to that short bow tang, eliminating all shackles.
You can use a simple loop on the other end, without twist shackles. Just pin a bow shackle to the single hole of a 10 hole adjuster, (allows for variable mast rake). The loops of the bridal wires are captive in the bow shackle.
However, if you intend to add roller furling to your jib, (highly recommended), make both ends of the bridals marine forks. This allows the use of a single triangle plate to attach bridals to the furling drum.
See the photo Portuguese Turnbuckle in this album.

If you are getting new rigging made, have the forestay made 3.5” shorter than stock, with a pigtail at one end.
The furling drum & swivel will make up for the shortened forestay

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Aug 05, 2021 - 09:04 AM

Tom is correct, you should only have a single hole, in a small tang, on the INBOARD side of the bow,
If the age of the rigging is unknown, I would have a new set of wires made.
Spend the extra few $ & have them made with marine forks on one end. Then you simply pin the fork to that short bow tang, eliminating all shackles.
You can use a simple loop on the other end, without twist shackles. Just pin a bow shackle to the single hole of a 10 hole adjuster, (allows for variable mast rake). The loops of the bridal wires are captive in the bow shackle.
However, if you intend to add roller furling to your jib, (highly recommended), make both ends of the bridals marine forks. This allows the use of a single triangle plate to attach bridals to the furling drum.
See the photo Portuguese Turnbuckle in this album.
https://www.thebeachcats.…pictures?g2_itemId=88291
If you are getting new rigging made, have the forestay made 3.5” shorter than stock, with a pigtail at one end.
The furling drum & swivel will make up for the shortened forestay

Edited by Edchris177 on Aug 05, 2021 - 09:09 AM.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
tominpa

Rank: Mate

Registered: Jul 29, 2015

Last visit: Apr 23, 2024

Posts: 577
Posted: Aug 05, 2021 - 11:30 AM

MN3
Quote but that would tell the tale. The images in your post are not even close to what I see on mine.

not sure what you mean "that would be the tell tale"

as per the images not being close to what you see - do you mean the style of the bow tang itself?

Mystere's use something like this but it has no kink and my welder added a SS bar at the correct spot

The only way I know to see the bow tang attachment in the N 5.7 is to remove the forward deck lid. This is a procedure many have done using a putty knife, hammer and re-attaching with thickened epoxy after the repair is complete. There are several threads. It's clear the bridal tangs on this particular 5.7 have been modified, so I would want to open it up, attach a new bow tang and probably replace the bridle wires and forestay.

EdChris, I have longed for a furler and never done it. It would save all that flogging on the beach.

--
Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
--
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Aug 05, 2021 - 10:22 PM

QuoteEdChris, I have longed for a furler and never done it. It would save all that flogging on the beach.

I think I have an almost new furler sitting somewhere amongst bins of extra parts. I know for sure I have a new one for the Dart, & a rebuilt H18.
I’ll have a look for the Harken system.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
MN3

Rank: Master Chief

Registered: Jun 20, 2006

Last visit: Apr 06, 2024

Posts: 7088
Posted: Aug 06, 2021 - 08:17 AM

QuoteThis is a procedure many have done using a putty knife, hammer and re-attaching with thickened epoxy after the repair is complete. There are several threads. It's clear the bridal tangs on this particular 5.7 have been modified, so I would want to open it up, attach a new bow tang and probably replace the bridle wires and forestay.

Unfortunately a small sledge hammer and chisel were required to remove my mystere decks. I almost cried .. lol
Andinista

Rank: Mate

Registered: Aug 18, 2003

Last visit: Dec 13, 2023

Posts: 880
Posted: Aug 06, 2021 - 10:51 AM

tominpaThe forestay bridle chainplates are accessible and repairable by opening the top-deck at the bow. The part you need is here: https://www.h2o-sensation…-vorm-2000000001951.html This thread discusses the same failure in a N 5.5. https://www.thebeachcats.…ms/viewtopic/topic/18322

Hi guys. That N5.5 is mine, unfortunately it has been sitting without intervention until now.. combination of Covid, winter here in Chile where I live, and not a lot of proactivity from the guy that will repair it (not something that I can do myself..). I should have something to report in the next month or two, to provide some feedback after the support from fellow sailors of this community.
stufish

Rank: Lubber

Registered: Jul 02, 2021

Last visit: Aug 06, 2021

Posts: 11
Posted: Aug 06, 2021 - 12:47 PM

Thanks all for the feedback. I've already got the deck up to repair the fiberglass further back on the hull which was pretty easy. I'll post pictures along the way.
tominpa

Rank: Mate

Registered: Jul 29, 2015

Last visit: Apr 23, 2024

Posts: 577
Posted: Aug 07, 2021 - 09:22 AM

Stufish, I am looking forward to a picture showing how the tang is anchored in the 5.7. Please be sure to follow-up.

--
Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
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