I've got an older Nacra 5.2 (1985) with a center tube and jib wires running on top of the trampoline and no grommet holes for dagger boards or trapeze. After alot of googling, i discovered that apparently most people have removed the center tube. I definately want to get the jib lines (mostly) below the trampoline. (In a Nacra, the jib blocks anchor to a position aft of the mast, thus the cables that run from the mast cross beam to the rear cross beam).

In order to install grommets, I figure I'll need to remove the trampoline for someone to sew reinforcement patches (this will also require drilling out rivets and removing center tube). Is there a kit of some sort to allow this to be done in-place, or is it necessary to have reinforcement patches?

It's sort of odd that the trampoline is captive on the center beam. It's also odd that the people would remove a structural element and not compromise the boat in some way. Thoughts, experiences?

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Pairajacks
1985 Nacra 5.2
Corvallis Oregon
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there should be lot on this in the forum archives that can be found by searching and also photos in the galleries here

- basically if you want to remove the tramp tube you will need to stainless/monel rivet the front beam straps to the beam to stop it rotating

- the jib wires can go under the tramp if the saddles are also moved below but the wires will need to be slightly longer to do so, or use a high tech not-stretch line

http://www.thebeachcats.c…5287ad5554a7fb8ad8690b6a

http://www.thebeachcats.c…ictures/?g2_itemId=74166

- most people cut slots in the tramp to bring the wires up for the blocks with sewn on reinforcing, but i decided on plastic eyelets, you just have to be very sure of where you want the blocks to go





- i thought the tramp tube disappeared from the 5.2 before 1985...what's the hull number at the back of the boat?

- later 5.2's, 1985 onwards?, had the jib block position moved out closer to the hulls, that's the position you want to copy

a few of the previous threads

http://www.thebeachcats.c…s/viewtopic/topic/12097

http://www.thebeachcats.c…rums/viewtopic/topic/437

http://www.thebeachcats.c…ms/viewtopic/topic/13308

http://www.thebeachcats.c…s/viewtopic/topic/11816

Do some searching through old threads, there are quite a few on this very subject.
ERICE wrote a fairly long piece on before/after.
Look also for threads on rebuilds of the 5.2, quite few people documented removing the bar. I have not, to my recollection seen a post fron someone who liked it better the old way.

HA HA Eric was busy searching while I typed!



Edited by Edchris177 on May 05, 2012 - 06:05 PM.

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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
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the bar is simple to replace. But you absolutely must stainless or monel rivet the beam straps to the beams to keep them from rotating. If you don't do that the front beam will rotate forward mast and all - not a good thing.

To put the jib lines under the tramp, the easiest way I found to do it is to get a spur grommett kit from Murray's take the mark the locations and install spur gromets in front of the daggerboard and behind (i can measure them for you this weekend), you shouldn't have to install reinforcing patches for that. however, a better solution is to take the tramp to a local sailmaker or upholsterer and get them to sew 6" wide slots into the tramp with reinforcing strips. This gives you some leeway for the lines to move around. I installed the saddles under the tramp at the same location as the originals, just under the tramp slots. I probably could have moved them outboard quite a bit and that would have cleaned up the tramp a bit. I got rid of the wires and switched to 1/8" vectran high tech line tied with a bowline at one end and a truckers hitch at the other which allows met to tighten it with 2:1 purchase. I also bought some clear 5/16" Inside diameter clear rubber hose that I slide over the line to keep the jib blocks from fraying it. I ended up moving my blocks farther forward than recommended to give me more room on the tramp and since I'm not racing it works just fine for me.

Take a peak at my photo album where I documented most of my upgrades. http://www.thebeachcats.c…ictures/?g2_itemId=74145 Airborne's gallery is also good http://www.thebeachcats.c…ictures/?g2_itemId=83788

Here are some good pics from Yurdle of the below the tramp system:http://www.thebeachcats.c…ictures/?g2_itemId=83788

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Oops sorry Erice, looks like you had it covered.

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Hey thanks guys, you rock!

I think I'm going to keep the center tube in for now; I'm thinking the hardest part will be reassembly of the hulls and crossbeams. I'll need to force the two hulls apart far enough (under the tension of the trampoline) that the spacer clip attached to the underside of the rear crossbeam will engage. Looks like the last 1/8" or so is a wedging action to tension the tramp, at least in the back.

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Pairajacks
1985 Nacra 5.2
Corvallis Oregon
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I think you are overthinking it. Once the mast is down it's a piece of cake as long as you can get the strap bolts off. If they are sticking or seized you need to soak them withe screwloose or some such penetrating oil. If they were greased properly when installed it shouldn't be a problem. The bias cut tramp doesn't require you to tension the tramp that way. All you have to do is make sure the hulls are aligned and the tramp isn't overly loose, tensioning from the back will give you plenty of tension. Take a look a the assembly manual in the technical gallery.

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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I was thinking about removing the center bar after I got my 5.2. Decided to sail the boat for a bit befor taking it apart. Am glad I did. I am 6'2 and the bar has been a great foot rest when not trapped out. The jib upgrade is is on my list however.. I did see a 5.2 that had the stock wires covered with foam pipe insulation. That was rather slick bit the retro thing is the best solution in my opinion.. Hal

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Hal Liske
Livermore CA
H 16 (6+ 1.. Friends) H 3.2 N 5.2 (2) H 17 (2) H-18
Nacra 5.8 (son's) H 20 (Friends)
It's a Sickness

I Need a A Cat Please
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