When varnishing a boat, it's crucial to choose the right varnish product that meets the needs of the surfaces, your own preferences, and the time available. If you want to achieve a magnificent gloss and depth, genuine oil varnish is the best choice. Although urethane, alkyd, and two-component varnishes are good alternatives, their use can give a wooden boat a plastic-like appearance and feel, and flexibility is limited. Therefore, traditional oil varnishes such as Le Tonkinois, Epifanes, Rylard or Spinnaker are excellent options for boat varnishing. In this article, I'll share tips for using these varnishes, but the tips are also useful for applying other varnishes.

It's important to note that, when used correctly, each of these varnishes can produce a beautiful and durable finish. While you might hear strong opinions for and against different brands, the end result depends more on the person wielding the brush than on the product itself. Of course, there are differences between various varnish brands. Epifanes is particularly popular among professionals due to its additional products, whereas Spinnaker has a narrower product range. Rylard also offers some impregnation oils, while Le Tonkinois's product range is constantly expanding and includes various colored oil stains, thinners, brush cleaners, flattening agents, impregnants, and three different varnishes.

However, meticulous work, including preparatory steps, is most important, rather than what brand is on the can. This ensures a magnificent and durable result that you can admire for a long time. When you choose the right varnish product and work carefully, your boat's varnish can last for years.

Do you want to know more about different boat varnishes? Read the article best varnishes for wooden boats, where we discuss different boat varnishes, what options are available, which varnish suits which situation, and what to consider when making your choice.

Preparation
Pre-treatment of the surface to be varnished Sanding untreated wood before varnishing: Coarse wood material: Sand along the wood grain with dry sandpaper 60 + 80 + 100 + 120 + 180 + 220. Normal wood material: Sand along the wood grain with dry sandpaper 120 + 180 + 220. Progress from coarser to finer until the surface is smooth and ready for varnishing. Cleaning: Ensure that the surface to be varnished is clean, dust-free, grease-free, and dry. The moisture content of the wood should be a maximum of 17%. Degrease mahogany and other non-oily wood types with a degreaser. Degrease teak and other oily wood types with a degreaser. Ensure that the solvent has completely evaporated before varnishing. Remember to wear protective gloves!

Rot Damage
Remove all rotted wood. Replace the removed material with a new piece of wood only slightly thicker than the removed piece. Glue carefully. Allow to dry and sand the surface level with the old wood. Carefully remove dust with a dust brush and tack cloths. Degrease once more before varnishing. Tinting wood: If you want to tint the wood, you have a few options. We have impregnating oils that are pre-tinted. In addition, there are oils that can be tinted, for example, with spirit stain. The varnish can also be tinted to your desired shade, or mahogany stain can be added to it.

Impregnating Wood:
There is a separate article on this topic here.

Conditions
Ensure that the conditions are favorable. This is probably the most challenging part of boat varnishing. In spring, when the enthusiasm for varnishing is high, the weather conditions are not always optimal for a successful result. The temperature must be at least +5 and no more than +20 °C throughout the drying time of the entire varnished surface, i.e., 1-2 days. The relative humidity of the air should be below 70%, as high humidity leads to a dull, uneven, or wrinkled varnish surface. Too cold or too hot also cause their own tricks. In cold, the varnish is stiff and difficult to apply. In too hot, the varnish dries too quickly and therefore does not have time to level properly.

VARNISHING:
Remember the correct thinner and thorough mixing. Avoid forming air bubbles in the varnish. So don't whisk unnecessarily, but stir with a stick. Applying a new coat of varnish is usually possible 24 hours after the previous coat in suitable conditions. When varnishing, there are many ways to achieve a perfect result. The most popular and easiest methods are traditional brush application and mohair or velour roller. After rolling, the varnish is smoothed with a brush to obtain a smooth and high-quality surface.
Spray varnishing can also be performed, but it requires a little prior experience.
The most important thing is to spread the varnish evenly on the wood and finish with a brush along the wood grains. This way you will achieve a professional and durable result!
Remember to wear protective gloves!

1st coat Wipe the surface with degreaser and a lint-free cloth Thin the varnish by 50% with its own thinner Apply thinly, but so that areas that immediately absorb the varnish are treated with a wet-on-wet technique until the wood no longer instantly absorbs all the varnish Allow to dry for at least 24 hours If you varnish over a linseed oil-impregnated surface, the first coat of varnish often dries very slowly

2nd coat Intermediate sanding with 220 dry sandpaper Carefully remove dust with a dust brush and tack cloths Thin the varnish by 40% with its own thinner Apply thinly with a good quality varnish brush Allow to dry for at least 24 hours

3rd coat Intermediate sanding with 220 dry sandpaper Carefully remove dust with a dust brush and tack cloths Varnish again with 30% thinned varnish Allow to dry for 24 hours

4-8th coats Intermediate sanding with 240 dry sandpaper – 400 wet sandpaper, gradually reducing the grit towards the end Carefully remove dust after each sanding with a dust brush and tack cloths Thin the varnish by 20-5% with its own thinner, gradually reducing the thinner Allow to dry for at least 24 hours between coats Varnish the last coat with max 5% thinned varnish

Boats should be varnished with 6-8 coats during the first varnishing, and after a year or two, 1-2 additional varnishing sessions can be done, which will result in a strong and very durable surface for the boat. Many have probably heard of boats with up to 20 coats of varnish. Often, the layers have accumulated over time, and it is not necessary or advisable to try to achieve a similar result during the first boat varnishing. The varnish must be allowed to dry completely before the boat can be launched. This usually takes about a week from the last varnishing session.

With the instructions above, varnishing should go smoothly, no matter which of our quality oil varnishes you choose. Although the product is "boat varnish", it can also be used to varnish many other surfaces.
Below is an indicative table of how many coats of varnish are needed for each surface
Boat exterior 6-9
Boat interior 3-4
Wooden surfaces outdoors 6-8
Wooden surfaces indoors 2-4
Floors at home 2-4,
Floors in public spaces 3-7
Furniture 2-4
Decorative items 1-2
Metal 1-15

Tips:
Varnish kept indoors in warm conditions is more flexible to apply than varnish stored in a cold outdoor shed. In fact, if you wish, you can keep the varnish can in a warm water bath to make it easier to apply.
Remember to thin the varnish with the thinner specifically designed for it. The wrong type of thinner can ruin the varnish or weaken its properties.
Avoid forming air bubbles in the varnish. So don't whisk unnecessarily, but stir with a mixing stick. Store an opened varnish can upside down so that air cannot enter the can, and the varnish will last longer.
If you are varnishing small parts and using little varnish, it is advisable to pour it into smaller lidded and sealable containers. This way, the varnish will stay in better condition.
If the varnish is used slowly and the can is opened and closed frequently, the varnish will gradually start to dry into lumps in the can.
Filter the varnish with a suitable filter and store it in small, sealable containers with as little air space as possible.
Store brushes in a glass jar with turpentine. This way you avoid unnecessary brush cleaning.
Finally, clean the tools with brush cleaner. Allow to dry and store in a dust-free environment.
Degrease mahogany and other non-oily wood types with DEGREASER and teak and other oily wood types with this DEGREASER.
Dust settling on a freshly varnished surface can be avoided by varnishing in as dust-free an environment as possible and by varnishing the pieces in an upright position if possible.
Varnishing vertical surfaces requires careful monitoring for runs.
Wash brushes thoroughly with water and soap before the first use. Rinse and allow to dry for 1-2 days.

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