At the waters edge with my '83 5.0 the other day only a few days away from first splash (for me). Looking everything over one last time during a trial rigging, I decided to check the front beam pre-bend. There seems to be a lot written about this:

http://www.thebeachcats.com/forums/viewtopic/topic/11719

I find no factory documentation specifying the pre-bend or a factory method for setting/checking it (please post any factory information on this subject if you have it). The "snug up the bottom nut and go 3/8" further" makes sense, elegant in its simplicity. A compression tube is commented on which I didn't know existed, however it makes sense to prevent the tube from crushing when load is applied. Taking a peek inside my front cross beam I found no compression tube:



Panic and anxiety quickly set in as I thought, here we go again, one more obstacle to my first splash as the Indian summer quickly fades. Likely days to find the dimensions for the thing, procure material and fab it. Fortunately, I purchased an '84 5.0 basket case parts boat with a front beam. To my delight it had a tube which was lightly corroded. Here it is with dimensions should someone need to fab one:



So, did Nacra put out some of these boats early without the tube then add it after beam collapse episodes or did they all have it from the beginning and mine was missing due to oversight?

I appreciate the tips on installing the tube (tape to batten) and use of anti-seize in the above referenced thread (no pun intended). Any other comments and or tips on installing the tube are most welcome. Is it possible to install the tube without removing the dolphin striker as the striker rod must come out?

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Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
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You must remove DS rod. Scotch tape the compression tube to a stick, or batten. You will need a helper, have them slide it inside the beam, line it up & insert DS rod.
Nacra spec on tension is no more than 1/4" play in the V strap. That means 3/8" up from first contact.
The tube can be larger than 3/4", as long as you have room for the 9/16" DS rod to slide through.
Here is some info I put together on changing it,
http://www.thebeachcats.com/pictures?g2_itemId=73301

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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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Edchris177

Nacra spec on tension is no more than 1/4" play in the V strap.

Ed, where are these specs.? I don't find them in the manuals. Do you have a link?

Thanks

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Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
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Item 12, under "Maintenance"
http://www.thebeachcats.c…pictures?g2_itemId=35420

I'm in Shanghai right now, I'll have a closer look at our 5.0 on Wed. I have never seen the diamonds hang up on the shroud. I'm sure both boats have plenty of clearance.
Is your rigging way loose?

--
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
--

Thanks Ed. The rigging at first set was pretty tight. When the hanging problem came up the first thing I did was tighten it up as much as possible to no avail.

As always, I very much appreciate your input, but let's take the conversation concerning the hanging problem to that thread:

http://www.thebeachcats.com/forums/viewtopic/topic/15819

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Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC
--