Hi guys,

So I started sanding a section of my deck due to a few cracks in the paint (refer to my previous post). Anyhow, after sanding the paint back I put some pressure on the deck between the centerboard case and the rear beam and the top veneer of the ply in that section cracked a little. This area flexes a bit, and I knew I was going to have to re deck eventually, but it looks as if I might have to turn this into a winter project.

I have cut a small section around the crack, and it appears that the deck is made up of two pieces of 3 - 4 mm ply with a peice of foam sandwiched between them. The top ply has come apart from the foam, hence the flexing.

So it is looking like I may have to replace the section of decking between the front and rear beams. If anyone has any suggestions of the best way to do this, I'm all ears. my biggest concern is separating the existing decking without damaging the hulls. I'm sure someone has had to do this before, any pointers would be awesome.

Cheers and thanks in advance,
Andrew

I recently removed the deck plate of my Blade with a heat gun. It was very straight forward, as usual I should have been a little more patient. I've no idea if this method will work for you.

Hi Andrew

I removed the deck of my timber mossie with a router. I put a hole saw through the deck first then set the router at the exact thickness of the ply I found there.

Using a TCT bit I then ran the router over all of the deck that was attached to something. The TCT bit was essential as it ate through everything in the way including the nails.

This left only a very thin bit of glue over everything including the foam bulkheads. Any imperfections were then sanded ready for redecking when all the faults were fixed.

Roughly cut out the correct shape from a new piece of ply and glue and nail on ( make sure to use Monel or copper nails!) when dry use the router again, different bit this time with the little bearing at the bottom, and run it around the edge of the gunn'l.

A bit of a sand and a paint and your done... Sounds easy, probably takes 3 hours plus paint and the hardest part is putting the first hole in your Mossie!

Trevor

Andrew, if you have Facebook, search for Simon Hallsworth and check out the photos on his site of restoration of Sail #1762, Reincarnation. Not too sure how to do this if you are not a friend. Facebook is not a strength for me. I was a consultant for the exercise. Contact me if unsuccessful. ppearce@internode.on.net

Thanks heaps guys,

Using a router sounds like the way to go, and the method which reduces the possibility of doing accidental damage to the hulls. I will be removing the hulls from the beams this weekend and building some kind of a jig to hold them in place. I'll then take to them with a router and see what I find.

Philip, I have seen those photos on the Mosquito website. I have a feeling that the boat pictured has quite a few more foam bulkheads than what mine does (based on what I can see through the inspection ports). From the small hole I have made in the deck, it appears that the deck is made up of two pieces of 3 - 4mm ply with foam sandwiched between them. As noted above, the upper deck has separated from the foam in the area between the centerboard cases and the rear beam. The foam does not smell or look like it is in a very good state in that area and I am hoping that there is a simpler, and hopefully lighter, alternative to supporting the decks. This all depends on the difficulty of attempting to replicate the existing 'foam sandwich' decks I am removing, or ease of implementing an alternative support method.

I noticed that in the restoration photos of Reincarnation, the stringers were replaced with ply I beams of some sort? It looks and feels as if there is only one stringer running the length of the decks, I assume due to the foam core being able to support more weight. Perhaps the addition of additional foam bulkheads and I Beams such as this may be a possible alternative? Do you have any further details, or recommend any books, detailing how these are constructed?

I wasn't planning on doing all this work when I purchased this boat, and whilst I can't wait to get it on the water, I am actually starting to enjoy the experience of fixing it up. Hopefully once I am finished, I should have a decent boat which will last me a number of seasons, and some new woodwork skills I never thought I needed

Thanks again for your help.

Cheers,

Andrew
Assassin 1363

Nooooooooooooooooooooooooo,

it wasn't meant to be this hard. I'm sure we discussed fixing things after they broke so you could go sailing before the weather turned.

In answer to your other question the other day. When you come to repainting look into Durepox as in theory it is easier to sand and polish in repairs than the most.

I know, but then the deck cracked, and so I cut around the crack to patch it, then I saw and smelt the foam, and I couldn't just patch it knowing it was like that... My current car doesn't have a tow ball, so I would be using up all my favors very quickly borrowing friends cars to get the boat from Sugarloaf to home as new cracks appeared. I figure, considering I've started repairs, I may as well try and fix all issues I can find so that It doesn't give me issues once I finally start sailing it. There is sailing through winter at Sugarloaf, so I'll be still able to sail it once I'm done.

I will have a look at durapox, I haven't heard of that before. I think the reason why the paint was cracking in so many spots is because the previous owner painted it with automotive 2 PAC.

Thanks again for your help,

Cheers,

Andrew
Assassin 1363

Hi Andrew,

First, throw the timber composite deck away and replace with 4mm ply. I did mine (now done several the same way) using the same method as Trevor but replaced it with 4mm, albeit the ply had a layer of glass on each side. The glass adds strength as one side is in compression and the other in extension (the opposite).

As for paint, not sure where this "urban myth" of auto paint has come from, but I have done all my mossies in auto with not an issue and I am talking of about 6+ boats now (counting my son's, timber and glass) .. our boats would still be some of the best looking boats on the beach, my present one in metallic and now 3 seasons old... there is always the issue of quality and application.
We have and will continue to use 2 pk Polyurethane ... but then that is what marine paint basically is, and a car sits in the weather as much as a catamaran. I would not use auto tho' on a boat that is permanently moored and sitting in a marina.

Food for thought and you get what you pay for.

David
Salpicon de Resplandor, 1744

Marine paint is the same as industrial paints,, auto paints have different stuff in them, but use any one of them, auto is a bit harder as it is thinner than marine or industrial paints and more expensive. whats good to use is international paints as its easy to spray and roll and brush, easy to sand and easy to polish

Cheers guys,

I really appreciate the feedback. Interesting about the 2 pac, a big advantage of doing this vs patching things up is that I wont have to worry about getting it colour matched. I will be brushing the paint I end up purchasing (I dont think my landlord would appreciate me spraying paint in the garage - she lives next to me...) ;), I have heard good things about the International paints, somebody else has suggested a product call 'Norglass' apparently produced in Sydney.

I will probably replace the composite deck with some fibreglassed 4mm ply as you suggested, will 6 ounce square open weave type cloth be sufficient? I will probably wait until I have taken the decks off before purchasing any ply or glass, and will most probably have more questions!

Thanks again for all your help, it makes cutting holes in my new boat a lot less daunting...

Andrew
Assasin 1363