Well, the time has come and I need to dust of the tools and do some work on the boat!  Generally its in good nick.  It had to sit in a field for a few weeks before coming inside and its got a few dark patches where the cover was resting against the decks.  Also the anti-slip doesn't so I'm going to replace this also!  Problem is I don't know how to repair it?!  My original plan was to sand down the dark patches and varnish them up again.  Once I started sanding I quickly realised this would look stupid as the patches would be lighter than everything surrounding it!  So I carried on sanding.  Now the problem is how to get all the old varnich off!  I discovered sanding is dangerous as the veneer is VERY thin!  So tried a heat gun.  Problem with heat gun is where the varnish blisters it comes off fine but then you keep applying heat to remove the rest and darken the wood, so that was out.  Next tried nitromors.  The strongest must ridiculously vicious stuff I know of.  It didn't touch it, not even slightly!  Then tried automotive nitromors which does two pack paints.  Also didn't touch it.  Then bought some ditrinol type stuff which was recomended by respected boat chandler.  This also didn't remove the varnish and darkened the wood that had been stripped slightly!  Its an absolute disaster and I'm giving up hope now!  So, 2 questions:
1. does anyone know either someone who would be willing or a boat building I could pay to sort it?
2. if not how do I do it myself??? 
Yours, muppet with a hot air gun!  Oli.

Check the cvrda site for varnishing guide and forum for tips.

Olie

Have a look at the link under boats, hints and tips. There is a a section calledd 'idiots guide to varnishing' very helpful.

There are several contact numbers under other threads on this forum i.e Laurie Smart, Ian Lovering (Ashdown Marine)who you can call for a quote.

If you follw the CVRDA advice it really is a simple job!

Good luck!


Richard

I found that a good controlled way of removing varnish down to the wood was to get a bulk pack of stanley knife blades and just scrape.  

You hold the blade vertically and firmly and draw it across the varnish with the whole width of the blade in contact, in the same way as a cabinet scraper.  With a bit of practice, a satisfying amount of varnish comes off with each scrape.  

The down side is that the blades can get a bit hot, and are a little difficult / painfull to hold.  Extra care is needed on curved surfaces (carlins and Gunwhales) and you just have to go carefully while you build up technique, and not try to take too much off at once.

As soon as you think the technique isn't working, throw away the blade and start again with a new one.

I prepped my old NSM decks this way, having been through the entire process you described (scorch marks, nitromors and all).  

The scraper technique will also get rid of the faded layer of wood once you are down to that level, but as you have already observed, you have to be very, very careful not to go through the veneer, and you are better sanding.

Olie,
Don't go down the chemical route, it is unhealthy and a real mess and as you have found out, not that effective and costs money. Boat builders love a challenge and will do a professional job for a price. This could be anything up to £400 including the re-varnish. Lawrie Smart is certainly someone I would recommend.

The best and tried method is a hot air gun with variable temperature settings and a very sharp cabinet scraper (and metal file to keep sharpening the blade). Don't keep the hot air gun on an area to long as it will burn right through the vaneer. If it is just varnish the hot air gun will remove it reasonably quickly and a cabinet scraper will take care of the remaining bits of old varnish. It takes time and patients hence the labour costs of a proffesional. Epoxy and varnish require a combination of both of the above and an orbital sander. 
Remember that the vaneers are waffer thin and if you scratch through or sand through them you are unlikely to be able to match the original vaneer.

In the end it is down to time and patients or the depth of your pockets. One reason why Mr Winder has so many customers for his low maintenance boats.

Shave hooks are just the job. They have a long enough handle to stop your fingers getting burnt, are cheap enough to let you modify them ( on a grinder) for the tricky tight corners and they can be sharpened easily. B&Q is a good place to get them (other DIY shops are available) but take your time and be prepared to spend a lot of money on sandpaper for that fine finish!

Nitromors is fine on old traditional varnish (won't touch epoxy finishes in my experience.but a good tip is to get it off with a power washer - it does a great job.  Thanks to Chris Barlow for that tip especially in the cockpit of old ribbed boat where it is difficult to clean off the treated areas - just let the muck run out of the bung holes.  It does however remove rotten areas in the process - but you were going to have to replace those anyway - weren't you?!!

Especially if you add a bit of pumice powder.

I almost always scrape paint/varnish/virtually any finish using scrap glass (I have a lot!) to try, cut a piece approx 3" x 3" with the edges very slightly convex. The side away from the cutter was used on is the one to use. The edge doesn't stay sharp for long so just cut the glass down by 1/2" and continue. Don't press too hard or use a very narrow piece to avoid breakages - cut fingers etc. Always scrape with the grain.
For anti-slip, I mask off the area not to be treated and apply a thick coat of epoxy where required then quickly sprinkle granulated sugar on the wet epoxy. Let cure then apply warm water to wash out the sugar. The epoxy creeps up the edges of the crystals to give a really good grippy finish. When eventually blunt (and so less grippy) wet and dry down and repeat.

Cheers,   John.

John - what colour does the epoxy dry to in these circumstances? Is it white, or clear (how clear)??
I'm wondering if I can create an anti-slip area such that it hides a dodgy plank where the ply got spoilt. If I get the filler colour right, will the epoxy hide the details?!

Scraping with glass does a great job but wear thich leather gardening gloves and buy elastoplast!!  Never been sure about the sugar trick if you don't get it all off in the wash then surely a recipe for bacterial or fungal growth and bacteria and fungi = rot.  I prefer the Salcombe sand idea with several coats of varnish to make it still non-slip but a bit less abrasive.  By the way G4 pond sealer is a very effective sealer and great for those antislip jobs as it dries fast and very hard.  It was used with great effect on 36 Terrapin restoration using G4 only, Gannet sealed all over and used on the inside only but on the outside of the hull and the decks coats of traditional varnish were put on top. It does seem to be very resistant it's not expensive.  Available from Aquatic shops and on ebay etc.

Use budgy (as in budgerigar)sand from any good pet shop. works wonders!

Hi Mags. Colour is clear but quite opaque so should be able to hide a multitude of sins. I suggest that you try a sample on a spare piece of ply or what-have-you. You won't have to visit the pet shop or builders merchants or even Mill Bay, just raid the sugar bowl!! If epoxy is used, a whitish discolouration might affect some or all the area when wetted with water but this will disappear after a slight amount of use or application of nail-brush. This won't happen if two-pot polyurathane  is used instead of the epoxy. Epoxy is tougher but two-pot is harder. I have used epoxy, brother George is about to use two-pot!
I would not use sand if you paid me. It always looks rather poor and you will find it very difficult to remove when blunt - hot air guns, burnt edges, damaged veneers etc instead of a simple wet/dry exercise. Also, sugar gives a lighter result.   Cheers.