Daggerboard trunk repair

[Josh_sails]

Hello everybody, I’m new here so hopefully I do this right . I inherited a 7.7 meter trailer sailor off my late Uncle . He run a ground a few years back at the boat ramp and sunk it and it’s just been sitting in a paddock slowly getting rot so I thought I’ll get it home and see if I could sort it out . The hull is fibreglass and the top glass over ply. Problem I have is that the daggerboard trunk has been completely ripped off the floor of the boat and just looking for some advice to reattach it . I wasn’t going to say here how I was going to Repair it because I may be way off but . The hull doesn’t look cracked or damaged so my plan was to grind all the excess fibreglass off the hull and that’s as far as my thoughts got . I’ll upload some photos and any advice would be very much appreciated. The post that goes under the mask is getting fixed asap because it’s kind of half glassed into the trunk . Thanks all

 

[Tops]

Josh, do you have any pictures of how the trunk was pre-damage, or an idea of make and model?
First picture- is that the mast compression post with the winch for the lifting keel?
What is the size (fore to aft, crosswise, depth) of the main keel foil ?

I replaced the 'grid' (floors and keel board) in my 6.4 meter boat earlier this year. I had to support the boat so the hull did not spring out (temporary wooden cross-members port to starboard at settee height) or sag down during repairs (keel blocked on trailer). Most of it I did on the trailer until I pulled the trailer to remove the keel stub and swinging blade off the boat for refinishing and cable replacement.

Are you comfortable doing fiberglass work? Do you have good material vendors nearby?

 

[Josh_sails]

Hi tops
No photos pre-damage and make and model unknown . Yes that’s the mast compression post , I got a mate that’s going to fix that up in the next few weeks .

I took a few photos of the keel can’t remember off hand the measurements but they on the photos , it’s bloody heavy I know that .

Iv started replacing some of the ply in the back was hoping I could just do patches but once I opened her up she was a bit rotten. More work than anticipated , but I’ll get there .

The trailer was absolutely stuffed . While trying to pull it out of the long grass the rear Axel stay where it was before the drawbar ripped off . I’ll get it sitting on cradles and make sure to get the sag out before I start repairs on the trunk ( thanks for that , didn’t even cross my mind ) .

I’ll Continue to post progress photos for Redirection if or when needed .

Very much appreciated cheers Tops

 

[Tops]

Thanks for all of the nice pictures and measurements.
The way it failed seems catastrophic for water getting in the boat but in the same breath maybe not so overwhelming to repair.
With an unknown make and model, you will get less people chiming in for advice and/or advice may need to be taken with some reason to see if it applies nicely to your situation.
On mine, I ended up replacing existing plain plywood with marine plywood and using epoxy and DBXM1708 to replace the polyester resin and chopped strand mat capping I removed. I also included an extra layer of epoxy-compatible mat and epoxy under plywood items being glassed to the sanded and prepped hull. Corner joints were filleted and the lam schedules were checked with an online calculator to make sure they approximated the old ones for mechanical properties.

The only 'trick' I can think of that may help in your situation is to make a foam 'plug' to keep the hole in the hull and the hole in the trunk from shifting during re-attachment as resin cures. 50mm thick polystyrene insulation board x hole shape, covered with masking tape and friction fit into place. Maybe a rope handle to pull it out from underneath when you are done.