Moisture that does get into the wood becomes trapped by the hard, non-breathable varnish, causing extreme damage to the wood surface. These finishes (Deks Olya and International Dex 1&2 are typical, but there are others favoured by some boat-builders) were mainly developed by the Scandihooligans and are really good for boats that are going to spend a lot of time getting wet and living in wet conditions.K. I will admit it up front, I have never used any of these, so please take any of my thoughts with a big pinch of salt!
Our search for the ideal wood finish—relatively easy to apply, easy to maintain, lasts multiple seasons, and is affordable—began in 2007 when we took a look at the different types of exterior wood finishes on the market, their pros and cons, and how easy they were to apply (one-part varnishes, August 2007; varnish alternatives, October 2007; two-part varnishes, December 2007; teak oils and stains, April 2008).
Exterior wood entry doors, Wood garage doors, Entry ways, Wood shutters, Wood hand rails, Wood outdoor furniture, Interior window sills & frames, Planters, Wood trim on boats (above water line), Wood projects (birdhouses, mailboxes, etc.). Man ‘War Spar Varnish should not be used on: Decks, Stairs , House siding, Log cabins, Wood on boats below water level.
Once this was all sanded down and good to go we applied 4 coats of dulux interior wood white paint (waiting 8 hours between each application), but even after the suggested drying time and 3 months on the paint is still tacky, leaves dirt marks and impressions in the paint whenever you stand on it, and if any item is left on it when you pick it up it takes a chunk of paint stuck to it. Sounds like perhaps it hasn’t cured (it was quite humid and rainy outside over the few days we did this).
Edited to add… a few years ago, the short seminar on varnsihing at the Port Towsend Wooden Boat Festival…. was put on by a female pro… who recommend a modified resin sealer before any varnishing work. It is always best to pour the varnish into a supply can rather than varnish directly from an open can. This high solid finish was designed for marine and exterior surfaces such as boats, outdoor furniture, doors or any exterior surface where a clear satin finish is desired. This series of steps frequently takes as much time as shaping and installing the wood.
On the first coat or two, cut the tung oil with a citris solvent, which will help the ung oil penetrate deeply into the wood and follow with 2 or more coats of tung oil. Because varnish flows out very easily, you should not have to make double or triple passes with the brush. These would be good choices for an exterior door facing onto a large enclosed porch or for a protected porch ceiling. There are a great number of oils which can, and have been used, to make varnish such as linseed oil, tung oil, fish oils, and walnut oil. Rinse the scrubbed wood thoroughly-brushing is required-and let it dry completely.
Apply varnish to the prepared wood with long, smooth, even strokes, laying the varnish along the grain in strips the width of the brush. This dreaded syndrome is the single factor responsible for more fouled up varnish jobs than anything else. I’m an artist who paints in acrylics on wooden objects (small boxes etc) and usually seal them with a water-based interior varnish. Varnish is a clear film and is therefore subject to extensive damage from UV, even with special additives. These doors were oiled years ago and a couple had been contaminated with silicone.
When you have finished varnishing, rinse off the excess boat varnish with turpentine before putting the brush back in the oil. A large number of small bubbles is normally a sign that something in your technique of laying on the varnish needs to be looked at more closely. The Ronseal Diamond Hard is a Polyurethene varnish that potentially could go over to top of the paint, but I do feel that if the paint itself is not cured adding a Varnish will not solve the problem and may potentially cause more. Epoxy has an affinity for the wood and the sealer…the varnish has an affinity for the epoxy coat = win>>>win.
It comes as either a water based varnish or an oil based varnish, anything from satin varnish to high gloss and absolute matt. Today’s teak is mostly plantation wood that grows fast and holds little oil is softer and more brittle than the Burma variety. Well the problem is that they are so strong, you can never get them off again, well not without destroying the wood underneath. To get an idea of how much you can wipe a damp cloth across the surface of the bare wood.
Do not touch the brush to the rim of the varnish container; shake or tap off excess varnish inside the container or on a strike can. Long term protection for enhancing wood natural beauty.. Brush, Roller or Spray application.. Do not apply under 10°C.. Thinner: WS.. Coverage: 15 m²/l per coat.. Packing : 0.35L / 0.75L. After two years of testing, its apparent that two-part varnishes are the most durable type of exterior wood finish.
A power washer should never be used in the finishing or refinishing of wood; nor should two-part acid solutions, once popular in the cleaning of teak, that act by dissolving the wood. In experiment, I have allowed a shallow puddle of wood finish to dry on the surface of a one quart polymer milk bottle, and five years later, it is still flexible. The Oil will enhance the grain and darken the wood slightly but leave a natural hard wearing finish.
Testers applied dozens of exterior wood finishes (22 one-part varnishes, six two-part varnishes, 18 synthetics and satins/varnish alternatives, and eight teak oils and sealers) to small panels of bare solid teak. Leave it on the wood for several minutes to give the detergent time to suspend the dirt and the bleach time to lighten the wood, then rinse the wood thoroughly, brushing it to clear the grain. Varnish is mar resistant, and is suitable for decking, architectural millwork and exterior furniture. Varnish either hardens immediately as the solvent evaporates and creates a film, or hardens gradually (or cures) over a period of time.
Using an oil in place of a varnish is a good option as it’s easier to maintain and repair if it becomes, marked, scuffed or slightly scratched. And then when you apply a top coat product such as Hard Wax Oil or Varnish it will darken slightly also. They have been left standing on the surface for at least 12 hours, and not affected the varnish. Raw wood requires no finish maintenance, but will require some repair as wood degrades to the point of possible structure failure. In old ships various mixtures of tar and oil were used to coat wood and help provide improved sun and weather resistance.
Ask anyone who has ever used Epifanes High Gloss Clear Varnish and you will learn why it is considered to be the world’s best spar varnish. That, of course, is a marketing strategy, though free varnish wasn’t what got the product on the Bluenose in the first place. In my area (Northern CA) at least, this is standard practice and the use of this sealer greatly improves the longevity of the varnish coating because it goes a long way towards keeping moisture from getting into the wood beneath the varnish coat and thus prevents peeling and lifting. Use spray varnish only where brushing is impractical, such as on wicker or rattan.
Despite the difficulties with real tung oil, the market for a thinned varnish finish had been established. Now if you should be able to get all the varnish off without damaging the paint, you’re best bet is to get away from oil-based finishes all together. Iain Oughtred has experimented with oil finishes and it is commonly used in Scandinavian boats such as Faerings. Go for a high quality gloss varnish as the gloss has the highest resin solids content. Then keep your wood floors clean, while repairing splinters and loose nails, and they will look their best for many more years.
If the brush starts to pull or if you see small missed or thin spots, add about 1 ounce of thinner to the varnish. Once varnish starts to crack, it must be stripped and a new varnish coating applied. A Waterbased Interior Varnish would be suitable, to use although Interiors products tend not to have UV protection in them, and it is also worth noting that a clear Varnish will darken the wood slightly. Boiled linseed oil does not usually have UV inhibitors, unless the label specifically states that it is for exterior use. If spraying Weatherproof Varnish may be thinned by using 10% mineral turpentine.
All these factors and more mean that colour matching in the wood industry can be difficult and require lots of experimenting in order to get where you want to be. There is no easy answer to your question, but I don’t think that more sanding will help. Best results with varnish over raw wood are obtained with applying a first coat of varnish diluted 50-50 with mineral spirits, then applying 2-3 additional coats of slightly thinned varnish (1 part thinner : 9 parts varnish). But there is a way around the problem: Thin the varnish so it cures faster (the thinner film combines faster with oxygen in the air), levels better and releases bubbles easier.
In the real world, all of the one-part varnish and varnish alternative test panels would be due for a maintenance coat, and some—like HMG K Type Varnish, West Marine WoodPro Plus (rebranded Epifanes Rapidclear), and Ace Spar Varnish—would be overdue. If the wood is protected from the elements by shade, such as a porch, you may only need to reapply the oil once every few years. So in the very recent years, the aim of research has been to make varnish porous.
If you are applying in cool weather we recommend heating your project to a minimum of 55 degrees farenheit and also placing the varnish in a pan of hot water to warm it. The biggest overall decline was within the one-part varnish test group: Not a single one rated better than Fair for coating integrity or gloss retention, and nearly half of the test field was retired after this rating round.