Repairing Nacra 5.8 hulls

last season a friend of mine and i went out in about 20-25 knots of wind off of newport RI. it started getting preety choppy but i didnt expect to much more. well after about 15 minutes while im out on trap i hear a loud bang. we had no idea what happened. after searching around we found that one of the staps that holds the hull to the cross member ripped out the hull!!! i scrambled to pull the dagger to relieve lateral stress on the hull. as soon as i reached over the forward strap on the same side ripped out. so the starboard hull was connected by two straps and started sliding inward. while all this was happening the rig started falling down. well after 50 minutes of ghetto rigged sailing back we managed to get back to the beach without having to ditch the boat. well now im looking for advice on how to patch this back up. ive tried putting the brass peice back in and fiber glassing but it keeps cracking and i don't want to go through it again. does anyone have any suggestions?
sounds like a big repair, pics of the damage would be needed by most armchair engineers for their advice to be of much use

there have been quite a few instances of people snapping boards on heavily loaded 5.8's in big winds and choppy waters

so much so that going out in a big blow just for fun seems to mean keeping the boards at least halfway up so the boat can side-slip away some of these lateral forces



edited by: erice, Jul 24, 2009 - 12:37 AM
according to my dealer (when I was having to re-tap after stripping threads during tramp replacement) the strap bolts/Plates are designed to part company by stripping threads to avoid what you describe. Thats why the tourque values on the bolts are so low. You must have had some serious twisting on that hull to rip the plate out. Normally there is so much downward pressure from crossbar to hull, the straps don't have much to do. I had folks telling me to use a thread repair kit but I chose
to drill out and retap to maintain the safety factor.

My advice..Call tech services at Performance Cats. They can tell you what needs to be done. A guy on my beach repaired this on his 5.2. so it can be done.
I had the inner brass piece on the rear beam pull out. This was on the stern side of the rear beam. After repairing the fiber glass, I installed a piece of 1" X 1" aluminum angle under the deck, from the inner to outer strap by using longer bolts through the straps. That was about 6 years ago, still holding.
I think there is a lot of upward force on the rear beam from the main sheet.
The front beam on your boat should not have moved in.
There is a bolt on each side through the beam into the hull to keep the beam from rotating under the pressure from the mast.





edited by: skarr1, Jul 24, 2009 - 01:44 PM
i used a fiberglass epoxy filler with the glass to cover the brass piece. its probably not as strong as regular epoxy and maybe thats why it cracked again. i also took a piece of bar steel that is spray painted to prevent rust and connected it under the cross beam to the inner and outer side of the hull. i dont know if this is a good idea because if it rips out again its gonna take the whole deck off. maybe that would be the sign that i need new hulls.
Im selling the nacra check out the repair we did and tell me what you think. its in the classifieds.



edited by: mariof, Aug 13, 2009 - 11:44 AM
Is it strong?
i went sailing with it and didnt get any cracks or didnt pull out. but it wasnt enough wind to fly a hull. but i was moving preety fast. i could have flew a hull if my crew went to the leeward side. doesnt help that our combined weight is 450 lbs lol.