Varnishing – with traditional varnish

Sumara of Weymouth in Oban 2021

The most common comment I receive when people walk past the fully varnished Sumara is:

“Looks great but, wow, what a lot of work!”

It does indeed involve a fair bit of work to keep a varnished yacht looking nice and shiny but probably not nearly as much as many people imagine. The trick is to keep on top of it and apply a coat or two EVERY year. It takes me a couple of weeks each spring but I rather enjoy it.

The text below is based on some notes I wrote for Flints Marine a while back. Maybe they will be of some help if you have a varnishing project. There is also a post specifically about this years annual maintenance if you scroll down through the posts.

Where to work

The ideal place to apply varnish is indoors out of direct sunlight and away from any breeze but, of course, sharing a dusty workshop with someone sanding their decks isn’t a very good idea either.

Indoors is the best place to varnish if it can be arranged – but check what the other boatowners are up to. If you see someone with a leaf blower just get out your shot gun quick.

If you are varnishing a yacht outdoors, try to ask the boat yard to position the hull so it is on a North/South axis. You can then work on the shaded western side before lunch and move to the shaded eastern side after lunch. You can even sit in shade under the boat to eat your lunchtime sandwiches.

The main problem with working outdoors is being able to predict when the weather is suitable, so if you have a looming launch date it may be worth considering hiring a covered space.

Actually an excellent solution is to start the preparation of the boat outdoors where you can use a hose to thoroughly wash down the hull with bucket of warm water and some washing up liquid. This will remove any grease, diesel and grit that might be on the deck. I like to use abrasive pads to abrade all the awkward bits like handrails etc. This work can even take place in the rain. Once everything is clean and the fiddly bits have been abraded, then get the boat into a shed for the final sanding and varnishing.

Wherever you choose to varnish, make sure you have good all-round access to the all the parts that you are varnishing as varnishing needs to be done without any interruptions.

How many coats?

I would say the absolute bare minimum is six coats of good quality traditional oil varnish and that assumes the boat is covered over the winter and not subjected to Med type sunshine. Of course you only need to do the six or eight coats when you are building up from bare timber, after that you can apply one or two coats each year. I think the “each year” is more important than anything else. If you have any dings or worn patches you will need to build them up with the six coats before the final top coats go on.

What about compatibility?

Traditional varnish can be applied over two pack varnish (once cleaned and abraded). A traditional varnish is one which requires white spirit to clean up your brushes. You can not apply two pack varnish over traditional varnish mainly because the stronger solvents will soften the substrate. Traditional varnish can be applied over epoxy coating but follow the epoxy manufacturers instructions carefully to ensure the amine blush is removed.


If you are applying varnish to an existing varnish you will need to decide whether to strip back the old coatings or apply on top. Often large areas of varnish will remain in good condition but there will be patches that have worn through or caught the sun. You should bear in mind that any patch priming will show up and this needs to be weighed against the time needed to start from scratch. Varnish gradually goes honey coloured over the years so generally patches will show up as dark areas. Note: This is not normally the wood that has gone dark but the surrounding varnish that has gone light. Don’t try to bleach the timber under these circumstances, it definitely will not help!

I normally accept some patches and put it down to “character” but every 10 to 12 years I reckon on stripping right back and starting afresh. Slight crazing in the varnish can normally be virtually removed with gentle sanding. The varnish will then disguise it but it is a tell tale sign of deterioration.

If you want to strip right back then the best method for very old varnish is a hot air gun and a scraper. It will lift off the varnish easily but keep the hot air gun moving so you don’t scorch the timber. Try to buy a heat gun with adjustable temperature control. Don’t ever use a blow lamp! Strangely, really thick old varnish will come off a treat but newer, thinner, layers tend to be more tenacious and a bit messy. For the initial lifting of the varnish a normal paint scraper will be fine but to clean up the timber it is well worth buying a couple of Bahco Ergo Scrapers which will clean off any final residue with ease.

Should you decide to use stripper then Blackfriars Paint and Varnish Remover is IMO the best type. It requires no washing down and will not discolour the surface. It is also handy to renew old brushes.

Prepare any bare timber using 120 grit abrasive, finish by sanding along the grain. Please don’t scrimp on the abrasives or the equipment. If you are varnishing every year, considerable time can be saved by purchasing decent sanding equipment such as Festool Sanders which have the added advantage of creating hardly any dust when connected to their vacuum units.

Skip the sanding process at your peril!

Once the sanding is finished, brush and vacuum the timber to remove as much dust as possible. An air blower fitted with a moisture separator can be very helpful to blast dust out of cracked splines etc. Once the dust is virtually clear, wipe down with Isopropyl Alcohol. It evaporates quickly unlike white spirits which soaks into the timber and can take hours to finally evaporate. Solvent entrapment is often the cause of varnish failure. Oily woods such as teak or iroko should be initially wiped with Acetone to remove any surface oil. Just before applying the varnish, wipe the surface with a Tack Rag to remove the very last traces of dust. A tack rag is an essential piece of kit for dust free varnishing.

Just seconds before varnishing, lightly wipe the surface with a tack rag.
Epifanes Rapidclear is useful for mending damaged areas quickly. Tessa Yellow masking tape is my favourite tape, and I have tried a few!

If you are going to repair small damaged patches before giving the boat an overall coat or two of varnish then I recommend neatly masking off the area to be patched up. You can’t get rid of brush marks by trying to smooth them out, it simply doesn’t work. Just sand back the damaged area with 120 grit until you have clean timber, then sand the nearby surrounding area with 320 grit and mask off a neat square or diamond. You can then build up all the layers needed (6) before removing the tape and applying the final top coats over the whole boat. You will see a small ridge where the masking tape existed, but it will be much neater than attempting to brush out the varnish away from the patch. Besides, these little repairs, like darns in a pullover, are a mark of honour in these times of reuse, recycle, repair.


One of the great things about varnishing is that it is quiet! You can varnish on Sundays without disturbing the neighbours or the boatyard curfew. It even gives you a chance to catch up with the Archers. Choose a calm still day, preferably not too hot. I aim to start varnishing as early as possible. As soon as the dew has completely cleared from the hull, I give the prepared varnish a final wipe down with a chamois and get started. The advantage being that I can normally get the hull of my small yacht varnished before any yard activity picks up and creates unwanted dust. However, on the first two coats it would be best to wait until there is some warmth in the air. I make sure that I stop varnishing in plenty of time for the varnish to set up before the evening dew sets in again. I would suggest working in the shade and finishing at least three to four hours before dusk. That will give you plenty of time to clean the brushes and get down to the boozer.

Varnish Choice

Epifanes Gloss Varnish – Lovely can!

I use Epifanes Clear Gloss varnish. It is a traditional tung oil based varnish. I first used it because I liked the label on the can. I use the same technique to buy wine – although that doesn’t always work. My varnish choice was reaffirmed when I saw that the experts in Antigua were also using Epifanes so I have stuck with it ever since.

There are several choices of varnish types available, and many manufacturers, so the choice of varnish can be confusing. As varnishing is a rather labour intensive task it is a false economy to try to save a few pounds by purchasing domestic grade “Yacht Varnishes” which sometimes have a warning “not for exterior use!”. Conventional single pack varnishes such as Epifanes Clear Gloss Varnish, International Schooner, International Original etc. provide a very high gloss, good UV resistance and reasonable resistance to wear and tear. They are flexible so they move with the timber and are a great choice for most traditional boats. Although they may wear quicker than two-pack varnishes they are much simpler to repair and are easy to use. These varnishes will clean up with White Spirit and can be applied over two-pack varnishes.

Two-pack varnishes will provide a long-lasting glass hard surface that will resist scratches, but they cannot be applied over conventional varnishes as the aggressive solvents will dissolve the coating below. Although they are ideal for stable substrates such as veneered plywood, I would not recommend them for traditionally built carvel or clinker built yachts. This is because the yacht timbers need to move and the glass-hard finish of two-pack varnishes may crack under these conditions allowing water to get underneath the finish. It will now be the devil’s own job to repair the damage.

If you want to reduce the maintenance to an absolute minimum, then you could consider using Coelan which can last for ten years but the finish will not be so glossy. Oils such as Deks Olje soak into the timbers rather than leave a coating on the top. They will not achieve a high gloss finish but rather a silken sheen. Oils tend to be a Marmite product with many fans but many others who are disappointed. My feelings are that they are better suited to wet cold northern climates rather than hot Mediterranean sun.

A quick word about Epifanes Rapidclear. This varnish doesn’t need sanding between coats and dries quickly, allowing two coats a day to be applied. It is a great choice for those repair patches. The finish isn’t as glossy as Epifanes Clear Gloss but if you gently sand the last coat with 320 or 400 grit you can safely apply the Epifanes Clear Gloss top coat over the repair.

The slightly satin finish of Rapidclear makes it a good choice for interior varnish work.

Epifanes Varnish PP Extra is a two pack high build quick drying varnish often used by boatyards to make good repairs in the fastest possible time.


For the first coat, pour 500 ml of Epifanes Clear Gloss Varnish into a spotless paint kettle and stir in 250 ml of either Owatrol Conditioner or the recommended thinner. 500 ml cans of Epifanes varnish keep much better than opened 1 L cans. I believe it is best to use freshly opened varnish rather than the second half of an opened can. Never dip you brush in the varnish tin.

Do not use White Spirits as a thinner, I know it is cheaper, but why mess up the whole job at this stage. The manufacturers make very specific thinners which are different for spraying and for brushing. It is important that the evaporation rate is correct. Save the White Spirits for brush cleaning.

Gently stir the varnish and conditioner in a separate paint kettle

Ensure the varnish and conditioner are well stirred whilst taking care not to incorporate any bubbles. Use with a good quality brush as large as you can handle. Purdy Pro Extra Monarch brush is perfect for covering large open areas as they hold a good quantity of varnish. If the area is fiddly, such as toe rails and coach roof sides try using a Polyvine varnish brush such as the 2” size. It is a wide but thin brush which can access awkward corners like behind pad eyes yet still cover small open areas such as margin boards.

These are the brushes after the varnishing. They are cleaned in double rinses of White Spirits, then brush cleaner and finally washed with soap and water. They are then either dried between paper towel or better still given a good spin in a paint brush spinner between each process. Finally they are neatly wrapped in clean paper ready for next use. I mark them out of ten on the paper saving the 9/10 for top coats (10/10 are new brushes!). If they get manky, I degrade them to “Paint Brushes”, which are an altogether different thing!

Make sure you have good access to the entire area you are going to cover. You must work fast and not stop or you will get lap marks when you restart. Plan how you are going to finish each area and use masking tape to provide a clean break line. For instance, do one half of the hull at a time with masking tape down the stem and around the transom defining the chosen area. Tessa Yellow masking tape is by far the best that I have used.

Keep the areas manageable. Don’t try to do the topsides, toe rail and margin board in one hit or you will end up with lap marks.

Stick up a sign saying “Do not Disturb – Varnish in progress” and turn off your mobile phone. Apply the 1st coat working it well into the timber with “X” shaped brush strokes. Clean the brushes and kettle ruthlessly. It is best to clean off the varnish in white spirits (or the appropriate thinner) and then repeat the process with clean thinner or a special brush cleanmer. Finish cleaning with washing up liquid and warm soapy water and wrap the brushes in neatly folded paper to keep the dust away. Poor brush hygiene is a common source of a sub-standard gritty finish.

Once thoroughly clean the brushes are wrapped in paper to hold their shape and keep off any dust.

Once the varnish is completely dry and hard – generally 24 hrs, but it may occasionally take longer – gently hand sand using 180 grit, finish with the grain. Velcro attached abrasives on a foam hand block are ideal. Better still use the Mirka Abranet system with a vacuum extractor connected to the hand block. Don’t skimp on the abrasives. Once the sheet has dulled off use another sheet. Spending on abrasives will save you so much time and improve the finish to such an extent that it will be money worth spending. Once you have gently sanded the first coat to remove any raised grain, brush down, vacuum and wipe again with alcohol and finally a tack rag. This time add slightly less Owatrol or thinner to the varnish. Apply the varnish to the hull working in vertical bands about 500 mm wide, work the varnish evenly and then “lay off” vertically with the brush held at 45° to the surface. You must maintain a wet edge, so work quickly and move on to the next vertical band. You now need to lay off across the leading edge of the first vertical band and the new varnish. If the first band has started to tack-up, you are either not working fast enough or you are working in the sun or a drying wind or you have not added enough Owatrol. Don’t worry, it is only the second coat! You should be starting to get a fine gloss. I am afraid that you need to repeat the process to build up the thickness to about six coats. You may need more coats if you are bound for the sunshine. After each coat use a progressively finer abrasive until you are using 320 or 400 grit. The trick with sanding is to be very light handed but very thorough. Try not to miss any patches.

Aft quarter with the fresh varnish.

Before applying the last coat gently sand the varnish until it is matted all over. You can now use water and a chamois to remove every single trace of dust. Damp down the floor too and wear a newly cleaned overall. Keep a new tack rag to hand and ensure that your kettle and brush is in perfect order. Avoid any distraction. Work in good light but out of the sun. You must keep that wet edge flowing. Only stop when there is a natural place to disguise the join. Once you have finished sit back and pray it doesn’t rain, or if you are inside, watch out for that guy with the leaf blower.

Roller and Brush Technique

Some people use a roller and brush technique which can work very well if you work with a partner. Using a wide Jenny Roller one person lays on the varnish while the other uses a Jenny Foam Brush to lay off vertically behind. The brushes and rollers are cheap so they can be discarded after use saving on solvents etc. and most importantly avoiding contamination. This technique is used by many of the classic boatyards and can give spectacular results. I always keep a pack of Jenny brushes on the boat for touch up work as cleaning brushes on board is not very environmentally sound.

Wet on Wet Varnishing

Building up varnish coats can be rather time consuming especially if you are having to allow the varnish to fully harden between all the coats and then sanding each coat back. A quicker and very successful method is to allow the varnish to set up just enough to allow a gentle de-nibbing between coats using an Ultra Fine Abrasive Pad. The time needed between coats will depend on the drying conditions, but the surface needs to be dry to touch. Very lightly de-nib the surface using the abrasive pad and some water. Dry off with a chamois and apply the next coat. The new coat of varnish will bond to the previous coat because the coat below has not fully hardened. If you are working indoors, it should be possible to apply two coats in a day. I always like to let the first coat and the second-to-last coat fully harden. I normally conventionally sand with 400 grit before the top coat.

Cover it up

Once you have achieved the beautiful finish don’t forget to cover it up over the winter. A good cover will save you many hours work. For the sailing season, make up some hatch covers out of Sunbrella or a similar material. Some transparent hose slit down its length can often by clipped onto the toe rails to act as a foot rest when climbing aboard and to prevent mooring and fender ropes from rubbing against the varnish. It will all save a lot of valuable time.

The cover almost rigged
Sumara and her mast all wrapped up for the winter

By the way, when I owned a Chandlers Shop I used to give talks on varnishing. You can find one of the talks here. Sadly the shop no longer sells varnish!

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