Nacra high aspect daggerboard repair

pt_pinos

Rank: Lubber

Registered: Aug 23, 2022

Last visit: Jul 27, 2023

Posts: 11
Posted: Dec 08, 2022 - 04:47 PM

I have a pair of Nacra Infusion high aspect daggerboards with a few small (>2cm wide/long) chips in the trailing edge, in the black area.
As far as I know these are carbon/epoxy construction. What would be the best method to fill these chips.
Is there a risk of water intrusion into the core with this damage or is it not an issue with this construction?
rehmbo

Rank: Mate

Registered: Apr 27, 2011

Last visit: Dec 13, 2022

Posts: 163
Posted: Dec 13, 2022 - 07:32 AM

Thank your friends with a C2 or Akurra as Goodall put together a nice video a few years ago that is a good primer on trailing edge repair.
https://www.youtube.com/watch?v=dIe7kMKuKfA

I've used this method on a pair of 12yr old C2 boards with success and they're still winning regattas. A few things I've learned over the years:
1) Use epoxy rather than polyester resin. It's about 2x stronger. West System is the standard.
2) Be very careful on the epoxy ratios. It won't cure to full strength if you're off by more than 5-10%
3) You need to maximize solid surface area for a good bond. That means you need to be fairly aggressive with the length of the V shape. The rise:run rule of thumb for scarf repairs is 12:1 I think. In one case my repair was asymmetric (ground more on one side than the other) to keep the scarf angle as shallow as possible without running into the white gelcoat.
4) Be careful of epoxy/cloth ratio and that you properly saturate each layer of fabric. CF is much stronger than the epoxy, but it needs the epoxy as the binder.
5) I used some pieces of plexiglass for my formers with lots of spring clamps.
6) I use wax paper as the release paper
7) I was lazy and got the CF cloth on Amazon. There are many other sources.

Best of luck. Don't be afraid to try. I was nervous at first, but even if you mess up you can grind it out and try again.

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Jeff R
'88 H18 "Jolly Mon"
'10 C2 USA1193
NE IN / SE MI
cramsailing.com
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