Nacra 5.7 questions :: Catamaran Sailboats at TheBeachcats.com

Welcome anonymous guest

Please Support
TheBeachcats.com

Nacra 5.7 questions

cbb

Rank: Lubber

Registered: Jul 02, 2009

Last visit: Dec 01, 2015

Posts: 36
Posted: Jun 22, 2010 - 02:18 PM

Hi - Getting my first real season on this cat and I'd like some advice on a few changes...

Currently, my only righting system is a knotted rope tied to the dolfin striker - I'd like to do better. Murrays has quite a few systems available. While I may get a pole system in the future, right now I'm just looking for the line. Any idea which would be most appropriate for this boat? Ideally, I'd like to be able to right this at 190lbs and a bag.

Mast rotation. My understanding is that this is not controlled on the 5.7? For a variety of reasons, I'd like to change that. Anyone have a picure or simple fix for this? Not really trying to tune it so much, as to limit its movement in light air.

Trap lines. I have one going through a grommet in the tramp, the other is passing through the forward cross bar. The forward one doesn't really run that clean, and my guess the bungee will fail shortly like this. is this correct, or is there a betty way to handle this?

Thanks

Chris
MN3

Rank: Master Chief

Registered: Jun 20, 2006

Last visit: May 22, 2024

Posts: 7089
Posted: Jun 23, 2010 - 10:31 AM

QuoteAny idea which would be most appropriate for this boat? Ideally, I'd like to be able to right this at 190lbs and a bag.

I think the big murrays bag would be needed (at a minimum). i now carry 2 since i have been unable to right it with just 1 bag

QuoteMast rotation. My understanding is that this is not controlled on the 5.7? For a variety of reasons, I'd like to change that. Anyone have a picure or simple fix for this? Not really trying to tune it so much, as to limit its movement in light air.

you can add a mast rotator limitor and if your cat is boomless run a line up to your main/clew plate..

QuoteTrap lines. I have one going through a grommet in the tramp, the other is passing through the forward cross bar. The forward one doesn't really run that clean, and my guess the bungee will fail shortly like this. is this correct, or is there a betty way to handle this?

the front one through the beam should be fine. if the bungee is old or freyed simply replace it with another one (much eaiser to connect the old and new one with a needle and thread and replace it than it is to break the old one and have to "FISH" it through the beam somehow.
yurdle

Rank: Mate

Registered: Aug 22, 2007

Last visit: Jan 07, 2015

Posts: 742
Posted: Jun 23, 2010 - 12:03 PM

Bag - the guy that sells bags on ebay (colorado bag co or something like that) used to make a really good one. He's since taken suggestions from sailors and improved it, which should make it even better.

trap shock cord - it's a great system if you have end caps for the beams. I imagine they'll fray and break quickly otherwise....a boat I'm currently in, so to speak.

--
Rob
OKC
Pile of Nacra parts..
--
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Aug 10, 2024

Posts: 2531
Posted: Jun 23, 2010 - 01:29 PM

I am also in my first season with the 5.7. Mast rotation was an option on the boomless models. Mine came with it, but it was Philip (MUMMP) or Ron Beliech who pointed out it was bent, & installed backwards! I removed the wishbone, straightened it in a vise, & reinstalled.
As it came it had 2 short lines, one goes to each fairlead & cleat on the main beam. I think I will change to a single line from the front of the wishbone, through one cleat, then loops around behind the mast, through the other cleat, then attaches to the wishbone. Murrays sells the wishbone, that's all you need, plus a bolt that goes through the mast.
I find that the wishbone tends to bang on the beam if not cleated, I'm going to install a short line to the mast that holds it horizontal. You are right in that it prevents the mast from banging around in light air, but it also is a great power/depower device. The other day, after tacking I was wondering what was wrong as the boat had no speed on the new tack, yet I had the same relative wind. Then I realized I had not released the rotator line, & the mast was facing the wrong way. Once released the mast popped around, with some authority, & the boat took off.
Here is a pic of mine in the backwards setup. The 2 lines at the top are the control lines, they are only a coule of feet long.

Nacraman57 had his upside down for a bottom job a few days ago. I noticed some lines underneath, I think it was a Hawaiian system & i asked him so send me some pics. Hopefully I got him before he righted the boat! If I get them I'll post them.
I got a bag from Colorado, seems fine, I'm going to actually try it in the calmness of my bay this weekend. It is a pretty big bag,(I think they told me 160 lbs of H2O, but I haven't filled it to check. Price was very good) I think you would have to be very strong to hoist the bloody thing on your shoulder, then grab the line & hike out. Mine came with a 3:1 purchase & cleat, seen here.

Either your shock cord is frayed to H.E.L.L., or the hole through the end cap is all torn up. If the end caps were replaced, maybe they used the rear ones, & drilled a hole with rough edges. My front ones have a preformed hole that encompasses a short tube,(1/2")this allows the cord to run quite smoothly.
Philip & Ron have quite a bit of time on this platform, they have been invaluable resources in my resurrection of this classic Cat, as I'm new to it, & Cats in general.

edited by: Edchris177, Jun 23, 2010 - 12:35 PM

--
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
--
cbb

Rank: Lubber

Registered: Jul 02, 2009

Last visit: Dec 01, 2015

Posts: 36
Posted: Jun 23, 2010 - 02:41 PM

Thanks for the replies. Edchris - to be clear - you would mount the rotator facing forward? I think I'll copy you single line idea as well, as it seems quite simple.

I have a small bag of questionable vintage and quality. more likely, I will use a climbing haul bag that is way better built, doesn't leak, and could probably hold 400lbs of H20 if I wanted (wouldn't that be fun). I was, however, really interested in what the best righting line would be. It would appear all the systems at Murrays reside under the tramp? Does this diminish the leverage you get trying to right the boat? (I had a H-16 years ago with a hawiian system that pulled over the hull).

My question on the trap line bungee is it seems to exit at a pretty sharp angle at times, wearing it pretty fast.

Thanks

Chris
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Aug 10, 2024

Posts: 2531
Posted: Jun 24, 2010 - 08:04 PM

I didn't know the difference when I first got mine. I posted some pictures,(an album, look for 1984 5.7)One of those two chaps pointed out to me that the wishbone goes forward on the boomless models. Here is a pic of MUMMPS boat, if you blow it up you can see the wishbone & the lines leading to the beam cleats.

I have to confess no firsthand knowledge of the Hawaiian righting sytem, only some descriptions. I'm hoping NACRAMAN57 will get back to me with photos of his setup. I think you could buy the line & fittings for quite bit less than what Murrays lists their system for.

--
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: Aug 10, 2024

Posts: 2531
Posted: Jun 25, 2010 - 06:10 PM

I took a photo of my setup today. What a great day to sail, started out nearly calm, but my wife wanted to go for a ride on my new toy. After about an hour the wind shifted & picked up to around 12mph, I wish she had a harness on, we easily had a hull out while reaching.
The lines on my rotator are crap, but they work. You can see how the bar drops down onto the beam, I think I'll add a small line upwards to the mast that will keep it horizontal. I haven't tried it yet, but I think a single line that goes around behind the mast would work better.
In the photo the boat is tied up to the dock, I cleated both rotator lines to prevent the mast banging from side to side in the gusts.
HTH

--
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
--
nacra55

Rank: Mate

Registered: Nov 02, 2004

Last visit: Aug 07, 2023

Posts: 626
Posted: Jun 25, 2010 - 06:52 PM

Revit an eye strap to the center of the mast and up about 18 inches and tie a line from it to the rotator to prevent the rotator from dropping down. The eye straps in front of your rotator cleats are for the rotator line to dead end and go to the rotator then to the cleat giving 2:1 purchase. Also a bungee tied from the bow tang going to the backside of the diamond wire then around the front of the mast, back around the diamond wire and to the bow tang on the opposite hull will keep the jib sheets from wrapping around the rotator.

--
Ron
Nacra F18
Reservoir Sailing Assn.
Brandon, Mississippi
--
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Aug 10, 2024

Posts: 2531
Posted: Jun 26, 2010 - 11:53 AM

Thanks Ron, I wondered what those 2 eyes were for. I was surprised at how much force there is twisting the mast.
I actually have a jib preventer bungee, just not on yet. I was going to run it through the eye on the mast that you clip the jib halyard to, but that leaves little room to actually clip the halyard. Your way sounds better!

--
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
--