Mirror dinghy restoration

Mirror Painter

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Hello All,

A couple of years ago a generous friend gave me the Mirror he had built about 30 years previously. The usual pressures of modern life mean that the boat has not moved since being put in the garden. It has worn covers, (in both senses of the word). The paint on the hull has flaked quite a bit although the wood appears sound. The fiberglass tape sealing the wooden sections is a bit suspect.

I've booked a work area at my sailing club for the next three weeks but have a full time job and a family. So I've got three weekends and an hour or two some evenings to work on the boat. The plan is to get stuck in next weekend and assess what needs to be done. Unless any horrors are discovered the minimal plan is to sand and re-paint the hull at least and buy some modern covers which shall protect the boat over winter. At this stage I am uncertain if just two solid weekends of sanding and painting are required or whether there's a great deal more to be done.

I shall post a picture next weekend but in the interim wonder if anyone has advice please?

Thanks.
 
In the mid 1960's I built a Mirror from a kit with my brother and a few years ago bought a Mirror again to teach my daughter how to sail, so you could say I know them quite well.

The biggest problem with wooden Mirror's is water entering the cover and remaining around the centre plate box and rot results. You will need to check this area carefully. This has been the end of too many Mirrors. Check the centre plate box does not let in water as any major running aground can strain the joint as the centre plate is a dagger board. Check the ply of the centre plate for damage on the bottom front corner and repair as necessary.

You need to check if the glassfibre tape seams are lifting, but these can easily be refixed with epoxy. If the interior is still varnished and showing dark areas, then moisture has got under the varnish. You can remove most of this by removing the varnish and bleaching the wood with oxalic acid. Once rinsed and dried, it can be varnished again and would recommend using a polyurethane varnish.

Stripping the paint off the hull and repainting would be a very wise idea. You never know what horrors might have been painted over.

These are the things that immediately come to mind. However you can also look on the Mirror Association website for more advice. http://www.ukmirrorsailing.com/index.php?option=com_content&view=article&id=340&Itemid=168
 
Take a good look at the glass tape on all the joints.

If water has got under it and it has started to lift you might find a lot of re-taping is necessary

Dont deliberately pick at it though because once you start to lift it it comes off very easily.

Originally they used polyester resin but epoxy would these days make a much better/ permanent job ... but at appreciably greater cost.


I have a small section lifting off my foredeck where water must have lain for some time last winter.

Not yet decided whether to stick it back down with epoxy or buy some new tape and re-tape that section. Got loads of epoxy left over from another job so will use that whatever .

Some years ago I bought a childrens Puffin dinghy. Sound but I ended up re-taping an awful lot of that!


Cant advise you on the time you will need to spend on it. Depends how much work you find is necessary and how fast you work. I hope this work area is under cover. I take it you cannot get it home and in the garage.

I reckon I could repaint the outside in two weekends but perhaps not if much needs re-taping as well.

BTW I have found that black heavy duty damp proof membrane is good stuff for covering the dinghies. Seems to be UV resistant and if not damaged lasts for years. ( The cover over the Mirror I think is polythene pond liner but still sound apart from physical damage after 30+ years out in the open. The cover over the little plywood tender is damp proof membrane and still Ok after a similar time but has split where the material was originally folded.)
 
Thanks Vic

I think what I initially thought was lifting tape may just have been lifting varnish (over the tape).

Thanks for all other advice - noted.

Yes, the work area is under cover. I do not have a garage!

Thank you.
 
Point of interest;

Fresh water (rain or lake/ river water) lying in your wooden boat will encourage rot - especially if leaves & twigs are added to the mix, so do take care where & how you store it. Under trees is pretty much a no no.

Salt water, while it perhaps shouldn't be left long term, still acts as more of a preservative than a destroyer.
 
It was apparent when we had a Mirror that probably the worst thing to do is to store it upside down and allow the grass to grow high round the trailer preventing ventilation.This appears to shed rainwater nicely but what happens is that condensation gathers inside on the varnish and runs down to the bow where it is trapped by the plywood 'knees',which have no drainage holes.These consequently suffer and can rot out prematurely.
Of course this wouldn't happen on a properly stored boat with cover.
 
Upside down storage every winter with mine when I sailed it - but it was lifted off the ground. That and a tarp over it kept it fine until the spring when I repainted and revarnished - and usually patched up a few splits where I'd mis-treated it the previous season too ... ;)
 
With regard to covers, try and keep the mast down and use a flat cover. They offer the best protection against water entering, especially if the mast is kept on the centreline to make a ridge for ensuring the rain runs off. Mast up covers are notorious for leaking around the mast, shrouds and the opening join. One easy way to reduce the amount of water tha can remain around the centre plate box is to fit self bailer. This should be at the lowest point and if a rope it passed through it and around the centre plate case should encourage the water to be wicked away by evaparation.
 
Epoxy, particualrly, and painting are not a good idea at present. Too chilly. Epoxy won't go off properly when it's too cold (the one I use needs 15 degrees C).
paint will bloom if the temperature drops too much after application and at this time of year most paint will take a wek or two to harden enough to handle. Despite what it optimistically says on the data sheets.
Unless you can get some decent heat in the area you are working, you need to limit yourself to what you know you can get done.
 
Some years ago my stepfather picked up an old Mirror dinghy from the local recycling centre and took it home to refurbish. He took a whole winter over it and I have to say that when he'd finished it looked like new. He spent hours and hours on that Mirror.
In the Spring, he presented it to my nephews to launch their sailing career on Rutland Water but it was felt that before being allowed out on their own, they'd take a beginners course at the sailing club.
Come the day of their first lesson, their Dad (my little 6' 4" brother) decided to take the Mirror out and join up with the boys after their lesson on the other side of the reservoir. All was going to plan until the first tack whereupon my brother moved to go under the boom and put his foot straight through the hull.
Thankfully there was a rescue boat not far away and the Mirror, now being worn on one leg by my brother, was towed to safety having sailed around 300 yards.
Unfortunately, far too many of the hours that my stepfather had spent working on the boat had been spent sanding the hull to get rid of the 'black stains'.
Be very careful that all the panels are sound before investing too much time 'refurbishing' an old Mirror.
That Mirror ended it's life as a flower bed in my in-laws garden!
 
I had a simiar problem, its a shame that Mirror kits came with such poor quality plywood. Cadets of a asimilar age (and layout) have fared much better.

Beware of having any damp if using epoxy. Epoxy hates moisture.
 
Firstly thanks for the further replies which I'd missed until now.

Secondly an update and two questions. The boat is in fairly good condition except for two things:

1. On an area about 6"x 3" there is wheat looked like a split on the hull (eek). Actually it's 'just' the top layer of ply where it has delaminated and then cracked. This is in an area toward the bow which will not be walked upon because it has a deck above it.

Do people thing some wood glue and weight might do the trick?

2. At the very bottom of the hull, along the ridge, one can see were the wooden panels were fiberglass taped together before being filled and then painted. This picture gives an idea but it is not as bad as that looked now I've sanded much of the flaking paint and filler away:

View attachment 46320

I think I could make things very much worse by trying to remove all the filler and tape. What do people think about applying more fiberglass tape over what is left of the tape and filler and then filling that before painting over the lot? Please note that I've just booked the club work area for a short while so am more interested in getting the boat protected from the elements than beautiful. I also take on Lake Sailors comments about paint / varnish and winter curing.

Thanks.
 
Thinking further about question 2 I'd like to modify it to:

What do people think about applying filler to what is left of the original fuller and tape, making it smooth and then applying new fiberglass tape over that?
 
Firstly thanks for the further replies which I'd missed until now.

Secondly an update and two questions. The boat is in fairly good condition except for two things:

1. On an area about 6"x 3" there is wheat looked like a split on the hull (eek). Actually it's 'just' the top layer of ply where it has delaminated and then cracked. This is in an area toward the bow which will not be walked upon because it has a deck above it.

Do people thing some wood glue and weight might do the trick?

2. At the very bottom of the hull, along the ridge .....
What do people think about applying more fiberglass tape over what is left of the tape and filler and then filling that before painting over the lot? .

1. Probably not, but see what other people say...

2. I know what you mean and I'd expect the proper advice to be to rip it all off and start again. However you are then into removing the keel band and then rebedding it afterwards. You say you've cleaned up the area a lot since the photo. If the ply still adheres to what's left of the filler and tape I'd say go ahead.

We have an old Mirror in the garage that I drag out now and again to do work like that (when the weather's fine and I've got the time). One of these days we might get it sailing again...
 
Thinking further about question 2 I'd like to modify it to:

What do people think about applying filler to what is left of the original fuller and tape, making it smooth and then applying new fiberglass tape over that?

The tape provides the strength and the filler makes it smooth. If there's no tape left in a patch, it needs replacing. If it isn't adhering to what's underneath it needs taking off and replacing. Then use the filler as necessary on top and along the edges to smooth it off.

You could use a bit of fibreglass tissue here and there instead of the tape (and that might be part of the solution to problem no 1)
 
It's just a tidy up/ repair isn't it, rather than a full restoration? In which case it needs to be watertight, strong enough to survive normal use/ abuse & simply look OK to the casual observer.

I'd paint it with resin & dab on a layer of light tissue then paint over the top. It will last a few seasons & you can then do the panel replacement if you want to.

Another choice is a tingle of ply on the inside over a layer of resin & maybe a couple of copper staples to hold it in place.
 
1. On an area about 6"x 3" there is wheat looked like a split on the hull (eek). Actually it's 'just' the top layer of ply where it has delaminated and then cracked. This is in an area toward the bow which will not be walked upon because it has a deck above it.

Do people thing some wood glue and weight might do the trick?

Don't pussyfoot about. If it's delaminated and cracked there is a good chance it affects the whole panel to some extent.
Try punching through it. If more cracking and splintering occurs, replace the panel. If not thoroughly dry it (a few weeks) and soak it with slow cure epoxy resin. I restored a Heron dinghy and used both methods, replacement and repair, to sort it.
 
Don't pussyfoot about. If it's delaminated and cracked there is a good chance it affects the whole panel to some extent.
Try punching through it. If more cracking and splintering occurs, replace the panel. If not thoroughly dry it (a few weeks) and soak it with slow cure epoxy resin. I restored a Heron dinghy and used both methods, replacement and repair, to sort it.

Thanks LS - have been flat out it over the w.e. and a day off today. As mentioned I have a short term use of the repair area at my SC and am trying to reverse a year or so of my neglect. I didn't quite punch the dodgy bit bit gave it a good thump (if you see the difference ). I squeezed wood glue in and the next day (!) Applied a generous amout of fibre glass repair filler over much more than the affected area. I sure this is not ideal but better than what I've done before (nothing) and I need to get the hull painted in the next two weekends.

Typing this on my phone during a tea break. Shall try to post an explanatory photo next.

Cheers
 
The blue stiff on the patch and along the seams is fiberglass filler. As mentioned, I'm having to go for a quick protection and make the boat use-able, not 'as new finish'.

The blue stuff near the gunwale is masking tape.

Sanded the filler a bit more after that photo and then applied primer to all bare wood - 2 coats. Hope to try a get a coat of undercoat on one evenng in the week.


View attachment 46361
 
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