Mixing varnish types?

rogerroger

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I've just varnished new internal lockers with about 5 coats of household (Ronseal) - clear satin varnish.

However, I've now decided I want them to shine more so went and bought a tin of International High Gloss Yacht varnish.

Will it be OK to just keep coating over the Ronseal stuff with this?

cheers


Roger Holden
www.first-magnitude.co.uk
 

AndrewB

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It didn\'t work for me.

'Traditional' yacht varnishes like International have a harder finish than domestic interior varnish. The rule with paints and varnishes is - never put a harder finish over a softer one, though going the other way is possible. Nor should you apply a high gloss varnish over a satin finish varnish.

I made this mistake with Ronseal a while back - the outer coat of varnish crept and wrinkled after a while.

Ronseal is a particularly nasty varnish anyway, best avoided in marine applications. But there are cheaper DIY 'yacht' varnishes like Blackfriars which give a decent finish.
 

AndrewB

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Re: It didn\'t work for me.

Sorry to have been so negative.

For that absolutely immaculate and durable finish, I suspect you would need to rub off the Ronseal and start again with proper high-gloss yacht varnish. Finish with a coat or two of satin yacht varnish if you like a matt finish, but being softer it isn't good in high wear places like lockers.

The alternatives are to leave things as they are, or take a chance and overcoat with high gloss. If the latter, leave it a couple of weeks airing the lockers to give the Ronseal the best chance of curing fully. Either way, I suspect you will be faced with doing this job again in a year or two. Beware if you see the varnish develop a whitish bloom, or any signs of the wood darkening along the edges, as both mean water is getting in.

Who knows though, with paints and varnishes it seems that different people find quite different things work for them.
 

rogerroger

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Re: It didn\'t work for me.

thanks Andrew. I think I'll leave things as they are, slap on a couple more coats of the satin maybe.

I actually brought home a small shelf to test if the gloss would go over the satin OK but I guess it takes more than a couple of days to know how it's going to come out (I was intending to do the gloss this w/e).

If I was to rub off the Ronseal I assume you simply mean with sandpaper ? The wood is teak veneered ply - would the veneer be damaged ?

Roger Holden
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AndrewB

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Sanding back - an art form.

You are quite right, sanding back to bare wood must always be done carefully, specially with ply veneer as eventually you will go through the veneer. With care, ply can be sanded back bare four or five times in its life before this happens.

Everyone develops their own method - the golden rule is a light touch and never, ever use a circular sanding disk.

I start with a thin layer of "Craftsman's" (spirit-washable) stripper to loosen the surface of the varnish, then remove the varnish with a Scarsten scraper. This requires care as if the scraper slips sideways it will permanently scar the wood. A slightly blunt blade is best, I find, don't press hard but add a light dab of stripper on obstinate patches of varnish.

Wipe with white spirit. Remaining surface roughness is removed with a flat "orbital" sander using 400 grade 'wet and dry', with hand sanding on curves and in corners. Finish by hand by sanding all over with 600 or finer 'wet and dry'. Used wet gives the best finish, but be careful not to damp the wood too much. The surface will then feel perfectly smooth, and if a little white spirit is painted on, should already look varnished. It is then ready for re-varnishing.
 

beneteau_305_553

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Re: Sanding back - an art form.

I've just sanded off a lot of old paint , varish and epoxy resin from the cabin sides of and old wooden boat using a DA sander and Norton abrasive pads with velcro backing. its a type of orbital sander but with some rotational movement. the discs last for ages and take off loads of old coating with the big advantage that its used dry. Creates huge amounts of dust though.

I made the mistake of using a polyurethane varnish on an old dingy and it looked great for a couple of weeks. it was too hard and cracked at the joints letting water in. I've always used soft yacht varnish since.



Richard
 

vyv_cox

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I've renewed all my bed boards and internal locker lids this winter, varnished with some DIY satin finish external varnish. Results look OK and they are unlikely to see any wet conditions, but they still smell of resin after two or three months. I conclude that the cost saving doesn't justify using this type of product .
 

ParaHandy

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Standing back - an art form.

After many years of closely observing the bod next door (with a quite magnificent carver hull sloop), I have perfected this technique and am willing to give lessons (hourly and at agreed rates). It is most relaxing and etc etc..........!!
 
G

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Andrew,

I was up in the middle of the night and took a look at your website. Lovely boat, lovely wife, the two of you obviously happy: life doesn't get much better for anyone. Also a very nice job on the lockers. About the varnish, I have a few thoughts.

Using an interior varnish on the interior of the boat is not such a bad thing. There are no UV filters on household varnish, but you don't need them inside the boat. Also consider the following advantage, a softer varnish tends to chip less with impacts than does a hard, spar varnish. Therefore a softer varnish is actually better for lockers and bulkheads, and other interior fitments. It is however, a very poor varnish for cabin soles. For cabin soles you need a very hard, and scratch resistant, (probably urethane) varnish.

Since you are five coats into the task with a type of varnish that is really ok for the job, and all you want is a little gloss on top, and you already own the spar varnish, I suggest the following. That you soften the spar varnish by the addition of some oil. Tung oil is good, and is available at furniture finishers, but it is a little expensive. Any of the various drying oils made for finishing teak are typically good, but you want to choose one with minimal solvents. You can mix the varnish and the oil about 2/3's varnish 1/3 oil, and this will give you a bright finish that is also flexible, and hence chip resistant. Of course you'll want to try a test patch to make sure that the mixture is alright.

To finish the cabinets I would simply keep going with a few more coats of the this oil enhanced (or "long oil") varnish, and you should have a finish that compliments the fine job that you have done on the cabinets.


So that is my advice.

Best wishes to you.

Robert Ishmael
 
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