The blog will now be devoted not to boat building but to my 82-year-old Vertue, Sally II, now undergoing a well needed refit at Johnson & Loftus in Ullapool (and gliding...)

Saturday, 19 November 2011

Choose Your Poison

I have just been asked to contribute a piece about modern methods of restoration, you know, how to epoxify your old boat for the next decade. But I found it impossible not simply to reiterate that old mantra: "Restore like for like". If she was copper fastened, with oak timbers, then replace with copper rivets and oak timbers. You can probably justify a little high-end mastic, rather than some ancient, highly toxic concoction, and I would say that epoxy for plank splits, and certainly over a plywood sub deck, are an old boat's life savers, yet generally the traditional stuff is best.

Six litres of Varnol went into the Honduras mahogany planks of this skiff, inside, while the numerous splits in the hull planks were fixed with an epoxy/dust mix, and the topsides then primed with Woodseal before varnishing wth Hempels' Classic

The exception to the rule was my devotion to the now-defunct Woodseal, a single pot clear primer by Hempels, which was great as a first coat under varnish and paint; a really tough first layer, which gripped the wood fibres like egg to a non-stick frying pan (at least ours, until we discovered that frying eggs in butter is the answer). Now it's back to old technology, and Varnol (sometimes mixed with a little Cuprinol) as a first coat under anything, varnish or paint. It also is magic for revitalising old, dried-up, brittle timbers.

 So here is my list of poisons. What are yours?

Paints and finishes
Varnol to prime bare wood surfaces, revitalise old, dried up timber and provide a basis for a paint or traditional varnish finish, which can be anything good from International, Epifanes, Hempels etc. Varnol, thinned up to 75% with pure turpentine, provides a superb foundation, which to some extent penetrates into and sticks to the bare wood, and the subsequent paint/varnishes. It can also be left as a final coat, which can easily be touched up by misting with thinned Varnol.

Underwater primer, as a base coat for bottom paint. I don't buy the expensive stuff from the top makers, as it's a pretty simple concoction and my local stockist, Norlands, have a perfectly good alternative at half the price. I'll try and remember the name...

Varnish, best quality from Hempels, (Classic or Favourite), International, Ravilak or Epifanes. No two-pack products. Again, Norlands do an excellent varnish, which is thick and brown and is called Sea Plane varnish, which I like the sound of. Good for general use, and nowhere near as pricey as the posh stuff.

Primer undercoat, (Hempels or International Pre-Kote) often mixed with proprietary enamel to give a semi gloss before the final topcoat. Norlands do a cheap one which is fine.

Hempels Multicoat (for a semi gloss finish that requires one coat, primer/topcoat: bilges in clinker dinghies, for example). Highly rated: tough and easy to apply.

Enamel, best quality ie International Toplac or Hempels.

Black bitumen, to seal the bilges on old boats, after soaking in Varnol, or as a last resort.

With the demise of UCP and Woodseal I am looking for a bulletproof, high tech clear primer, ideally one pot. I suspect I will need to go for International's two-pack clear primer UCP replacement, or the equivalent Epifanes, and try not to waste the mix.

Collano Semparoc for all laminating. I have also used it as an epoxy substitute when building a clinker ply pram (with epoxy fillets to strengthen joints and seal end grain). Much better than Balcotan, which bit the dust for some reason. I do not mourn its passing...

Epoxy, to mend splits in planks (mixed with wood dust from the plank itself).


  1. One part mineral spirits (or turpentine), one part linseed oil, and one part spar varnish (oil-based, of course). Put it on thick with a scrap of old towel or T-shirt. Let it sit for about an hour and rub it off with the rest of the towel or T-shirt. Repeat until you get the amount of sheen you want. (But wait at least 24 hours between.)

    About four or five coats give you pretty good protection. It's nice for floor boards because it's not too slick. If I want a glossy finish, I lay on a couple (or four or five depending on how crazy you want to get) coats of thinned spar varnish. That gives you a deep gloss finish.

    This is a beautiful finish that really brings out the figure and grain of the wood. It imparts a warm amber color to the wood. When you touch it it feels like you're touching wood too, not plastic. It also feeds the wood so moisture doesn't get under the finish. I've found it to be very durable too. But the best part is that it's easy to repair: Just use a little four 0 steel wool (or the grey synthetic stuff) dipped in the mineral spirits/linseed oil/varnish mixture, rub the damaged or warn area until it look right, and wipe off the excess.

    One variation I haven't tried yet is to add a little, maybe a tenth part, pine tar or Stockholm tar to make it a darker. This might be just the ticket to cover aged, dinged up wood.

  2. Here’s another recipe, this time for an all-purpose boat “soup” found on the internet, Apologies to whose it is. Maybe you will come forward?.

    The recipe is one part by volume good traditional resin varnish (any traditional marine spar or captain’s varnish , but not polyurethane varnish), two parts linseed oil, and three parts real turpentine (not paint thinner). Mix and apply with clean cloth.

    Put on two or three coats to start with, letting each layer dry well before applying the next. Drying may take from 3 hours to three days, depending on the wood and the weather. Repair faded or worn spots by rubbing on more boat soup as required. Remember the drying boat soup is sticky so don’t expect your best friend to sit on it 3 hours after you apply it! Generally once the base coats are established any spot of repair will be ready in a day or two.

    Adding a dash of Japan driers is specified in some boat soup recipes and that may speed the drying. I have not tried it.

    There are other boat soup recipes that include pine tar, a black gooey substance. They are good too, maybe more long lasting, but not so attractive for pleasure craft. They are typically used for outside hull surfaces you don't walk or sit on.