how to fix damage to wooden floor

Welcome to the forum!

I believe your problem is the result of the epoxy coating of the plywood cracking and subsequent water/water vapour intrusion (similar to osmosis damage in FRP boats) leading to delamination of the plywood at that point.
Before I finally did a complete overhaul of the centreboard case connection, I used a method similar to the one described below to infhibit further delamination:

- Make sure the plywood interior will be absolutely dry (may take weeks storage in a warm dry environment).
- Get some heavy, manageable objects as weights.
- Obtain a few relatively thick hypodermic needles and single-use syringes (my pharmacist first looked at me oddly, as I don't look like your typical junkie).
- Place the boat on a support so that the damaged area is as flat as possible on a firm surface.
- Mix epoxy resin according manufacturer's instructions, fill a few millilitres into the syringe.
- Punch the needle into the hollow (under the "lifted area" you mention) and inject epoxy into it until it oozes out of the hairline cracks.
- Wipe excess epoxy off the area.
- Place some polyethylene film (plastic bag will do) on the area.
- If the section is curved too much, you may need to place a thick piece of rubber on the film (I used an old flip-flop sole, perhaps a piece of insulation mat would do).
- Place the weights on the film (or on top of the rubber sheet) in order to apply pressure onto the damaged section.
- After the epoxy has cured, sandpaper and re-paint the spot.

The most difficult bit is supporting the underside of the bit that needs compressing. If it's on the outside of the hull, you can use a block of wood and a ratchet-strap (normally used for securing loads) or Spanish windlass instead of the weights to apply the pressure. Of course this is not possible inside the cockpit floor, which is why I devised the method using weights (I used a stack of three bricks).

Look at the discussion thread http://forum.mirrordiscussforum.org/node/35 for instructions on how to show pictures here. Sorry, it requires a bit of typing. I usually cut and paste the whole string and then just substitute the URL with the URL of my picture and the "alt" text with a text describing my picture.

Cheers and success with the repairs.

Gernot H.

Hello THombelli,
Those pictures indicate that you have probably grounded the boat on a sharp object. It looks as if something has punched a little hole in your boat. I'd let it dry thoroughly, glue the raised bit of wood down with epoxy, making sure it spreads into the longitudinal cracks, and then reinforce the outside with a strip of fibreglass (after sanding the area down to bare wood) for good measure.
For everyone else to see:

Wishing you success with the repairs.

Gernot H.

On Saturday I discovered that the top light of my daysailer "Anansi" had come loose and was dangling by its cable. I don't really need it but didn't want to lose it altogether, so I folded down the mast to remove the light. However the mast extends beyond the stern of the boat by more than a metre, so I got out "Puffin" and rowed to the masthead to get at the light.
A drop of water started forming at the edge of a reinforcement patch and a batten on the port side floor. So I have a problem there too. It'll have to dry for a while before I embark on a fix. When I do, I'll post a description in a separate thread.
Gernot H.

I have one leak a year. When I first put my Mirror in the water after being in the garage for a year I will get about a cup of water leak through the bottom some place, I don't know where. But then the wood swells and it leaks no more until the Mirror becomes completely dried out again.

Pete

A closer inspection of my hull showed very minute cracking on the underside. I scraped the paint off the area and applied a liberal coat of primer, hoping that it will seep into the cracks and remain flexible. Today I sanded it and painted over the area. Will do a complete bottom paint job in the off-season.
@ Bruce: I hope you get the "puncture" fixed quickly and can enjoy the remainder of the season.
Gernot H.

My Mirror is also developing some cracks on/in the floor. They look the same. I suspect balancing on the trailer and flexing the floor too much as the cause. Maybe I'm wrong. But I hope this is the reason for cracking, because otherwise I have a bigger problem.

Will try to patch with a piece of fiberglass tape on top and epoxy this on the floor. Hopefully this will be strong enough to hold for a while.

I'm a new member here, and new owner of an old (26383) Mirror. I have only just read the above discussion. A recent accident where my boat got pushed down hard on the sticky-up bit of the launch trolley caused a split in the hull about 6in long and a matching split in the floor above. I have patched both sides with epoxy filler inside the cracks then fiberglass to cover them, but I am worried by not knowing how the Mirror floor is constructed. Am I right that the floor is a wooden layer stuck down directly on to the hull plywood, or is there an air gap, and therefore a place for water to get in and do harm?

The floor on a Mirror is not a seperate item. The hull is made of 5mm marine ply. The outer face of this ply is painted and touches the water, the inner face has battens nailed and glued to it, is then varnished (or sometimes painted) and this is where you rest your feet.

Pushing some epoxy into the cracks and glassing over the top isn't a bad temporary repair and may keep going for years. I hope you removed the paint and varnish before applying epoxy. A proper repair would involve scarfing a new piece of ply in, a job for sometime later or the year after that.

Keep an eye on it and the floor batten alongside which sometimes start to come unstuck and end up weeping where water gets up the nail holes. A proper repair to the batten is a bit fiddly but can be put off until you next paint the boat. I can talk you through how I fixed mine if necessary.

In the meantime enjoy it. There's still a bit of summer left!

Cliff

That's very helpful - many thanks. Planning to take her out for a sail in a couple of days to see if the repair has worked. Peter

Some fool has gone and hit Sarah's little rowing boat and put a hole in it. Guess who has to break the bad news. Guess who'll end up fixing it. It shouldn't be too bad. The hole is small and the boat light enough to turn over. Thankfully it's a glass hull.

Cliff