Simon,
If I understand you correctly this part of the hull can experience quite high compression loads from the rig as well as coming off waves or big chop.

Given that I would also put a layer of 200gm glass over the crack after taking back to bear timber. When loaded up if the ply wants to seperate again the glass will prevent it even more affectively that injecting a resin glue mix. However I would do both.

Regards,
Phill

G'day Simon,

I noticed the photo of cracking on your hull and thought I should speak up.

I repaired a similar crack on my hulls with carbon fibre on the inside of the hull. The inside ply had a slight crack about 15mm long running down it too. The bow broke off eventually with what we suspect was the inside ply buckling right on the crack.

This needs to be repaired properly, and you might as well do both hulls at the same time.

Hey Simon
Did you see that there are a new set of hulls for sail only $8000ish I think Its time you took the next step.
Cheers

Thanks for the input guys. The hull has been reinforced with a false deck in this area and everything seems solid as internally. (Had a prod and a good look round with a mirror.)

I think the area in question has been that way for a while and given the generally heavy conditions we've had this season I would guess that any structural damage would have occurred by now.There is no sign of any damage down the side of the hull, inside or out. OR... I could be completely wrong. (I guess time will tell)

Ben... I'm having far too much fun learning all these new skills to give up on the old girl just yet. ( though I suspect that if I had $8000ish lying around those hulls might no longer be available.)

Cheers and thanks everybody.

Hi,

Have been doing some repairs and strenthening to mossie especially to carry kite.

My hulls appear to have carbon mat on inside in front of main beam bulkheads - see pic 1.

Have already relaid 200g 50mm tape along bottom keel from centreboard to bow, run a 50mm tape along outside gunwhale, reinforced side stay and bridle fixing points and pole brace points at bows. See extra pics.

What are thoughts on anything further? - carbon to outside of hulls in front of main beam, tape along inside gunwhale?

Want to achieve enough strength without going overboard and adding unreasonable weight.

Would appreciate the comments of others.

Generally speaking, there is no point adding carbon to plywood to increase strength. Plywood is so much more flexible than carbon that the carbon ends up taking practically all the load. If there isn't enough carbon to take all this load it can break and leave you where you started.

Much better to use fibreglass, it has similar stiffness to plywood.

On a productive note, some uni fibreglass down the inboard gunwales from cb case to bridle (roughly) might not go astray.

The kite isn't necessarily the greatest load on the bows.

Went with glue and glass. I excised timber beyond the crack and was pleased to see it went no further than it looked.

What does everyone use for sealant when putting the beams on. I had sikaflex-291 recommended by my shop but on reading the specs it seems to have a very long cure time? If it's good I'll use it but I was hoping to be back on the water by the weekend.

Cheers,

Just a small circular bead of sika around the bolt holes is enough. Should be right by the weekend, but give the bolts another tighten before rigging up.

Thanks ncik.