Teak - The king of boatbuilding woods

 

 

 Installing a teak deck. Teak not only looks great but is good underfoot and has natural non skid properties.

 

 

Of all the boat building woods teak stands head and shoulders above all the others and with good reason. It can be vanished to a lustrous finish, oiled or left to weather to a silver grey, virtually impervious to water born pest like the torredo worm it will last years with virtually no maintenance.

Teak (Tectona) grows predominately in southeast Asia most notably Myanmar (Burma) and Thailand. Teak is a large tree and once it reaches full maturity can stand 120 feet tall. Thus each tree can yield substantial amounts of useful timber.

Many years ago I was captain of a 72 foot wooden ketch whose main planking was solid teak. The boat was over 100 years old but the planking below the waterline was in almost perfect condition as we found out when we had to remove some of her copper anti foul sheeting. These days however cost considerations make the use of teak aboard into more modest proportions. Certainly in the recreational boat market teak is used mostly for trim and decking. There can be no doubt in any body's mind that a well varnished toe rail or rubbing strip can elevate even a fairly modest boat from the mundane to the beautiful. I have to admit that on my own boats I have an abundance of varnished teak which does take time and patience to care for but the complimentary comments that we receive when we are out cruising or the pride of ownership that I feel when I walk down the dock after a long week at the office make the hard work seem all that more worth while. Unlike many wood even teak that has been 'let go' can be bought back to a prize winning finish with a little elbow grease and time.

Varnishing teak

When it comes to varnishing anything there are a thousand different methods it seems for approaching the job but my technique has served me well for many years. There are also lots of different varnishes on the market including those that say you don't need to sand between coats. I am not necessarily advocating one product above all others but the best advice that I can give anyone is to try and product and stick with it. Follow the manufacturers recommendations and you will achieve good results. Get to know your varnish before trying something else. Do not chop and change just because you see some new wonder product at the boat show. Ninety percent of getting a good finish happens before you even dip the brush into the can. You can use the very best products out there but if you are sloppy in the preparations then the final result will be disappointing at best.

On previously varnished surfaces that are in good condition you will merely be prepping the surface for additional coats and you can skip this stage but on new wood or previously varnished surfaces where the varnish is far from intact then it needs to be removed and the wood taken back to bare. By far and away the most effective way to remove old finishes is with the use of a hot air gun and scraper. This is where I think that many get off to a bad start whose first inclination is to reach for the sandpaper. This is the slowest and least effective method of getting back to bare wood and it is also the most expensive. There will be times when you have no alternative but only resort to sanding as a means of removing a finish as a last resort.

One word or warning would not go amiss here and that is although a hot air gun is far safer than an old fashioned blow torch it can still set stuff on fire so be careful, keep the gun moving and only use enough heat to soften the varnish so that it will scrap off easily.

Work on one section at a time, be careful with the scraper to only remove the varnish and not gouge into the wood.

With all the old finish removed sand the surface with the grain using 120 grit paper. I like to use an aluminum oxide open coat paper which does not load up like the regular cheap sandpaper that you can buy at the home improvement store. 3M make some of the best papers which you can either buy on line from people like Fisheries Supply or Jamestown Distributors or you can get them from Napa auto stores.

The amount of work can be daunting so break down the work into manageable pieces. Burn off and sand a handrail say before moving onto the next area.

Once all the sanding is complete thoroughly dust down the area, use a vacuum if you have it and a painters dusting brush.

Tape off the areas so that varnish will not will not drip onto adjacent gel coat or painted surfaces. Stay away from the cheap white masking tape which does not come up cleanly especially if it is left in place for more than a few hours. Use the blue or green painters tapes which although more expensive are easier to remove especially if left in place for a week or more.

With the masking complete wipe down the teak with a suitable solvent using a clean lint free rag, cotton tee shirt material is ideal. Read the instructions on the can of the varnish you will be using; Interlux Schooner varnish is my finish of choice so I use their 333 solvent but acetone can be used at a pinch. Keep turning the rag, the solvent will remove surface oils and sanding residue from the teak.

You are now ready to apply your first coat of varnish. The bare teak will suck in the first few coats which should be thinned a little with solvent to allow them to be more readily absorbed, again follow the maker recommendations.

Do not use the varnish straight from the can, EVER, always strain the varnish through a disposable paint strainer as even new tins have bits in them that will spoil your finish. I like to use foam brushes of the disposable kind as they can be thrown out at the end of the job and a new one used for each new coat. Some varnishers like badger brushes which work great too but you need to clean them before and after each use.

Try to varnish under cover if at all possible on a warm dry day. Varnishing late in the day or when rain is forecast will affect your finish and can make it look dull and a little milky.

Leave the varnish to dry for at least 24 hours before applying the next coat. After the first couple of thinned coats you need to apply at least 3 more at full strength to provide adequate protection for the sun and water. But I will often go as far as 8 coats for a true deep gloss.

I like to wet sand between coats with 320 silicone carbide wet or dry paper. There is little to no dust, it cuts fast and the paper lasts ages providing it is kept wet.

Wipe down the surface before each new fresh coat of varnish and just prior to laying on the varnish go over the surface with a tack cloth to remove anything remaining that could mar the finish.

Once the last coat of varnish is complete remove the masking tape . Varnish takes about 8 days to reach full maturity so treat it with respect especially during this curing period.

Caring for teak decks

More teak decks have been ruined by too much love that anything else. Teak decks do not need oiling, sealing or treating with any other preservative but they do need a little care. About the best thing that you can do with a teak deck is to use plenty of salt water and a moderately stiff bristle brush to remove surface dirt. Avoid using a brush that is too stiff as this will scour out the softer wood and leave ridges in the deck. Scrubbing across the deck will go along way to prevent this malady and will also ensure that the deck seams are not placed under duress. Use plenty of water to wash away any dislodged dirt.

Teak is naturally resistant to rot and using harsh chemicals will remove the woods natural oils making it less able to naturally resist cracking and decay. If the deck has been neglected for a long period of time then some sort of teak cleaner may be appropriate. I've had excellent results with Teak Decking Systems deck cleaning powder. The deck is soaked with water, the power is sprinkled on the deck allowed to get to work and then simply brushed off using plenty more water. It works a treat but I would not recommend this as more than a once a year treatment at most.

Working with teak

Teak contains a fair amount of silica which can dull the edge of even the sharpest of tools. So if you new to working with teak then you will find that you need to sharpen you tools more often than was hitherto the case. Power tools require TCT cutters and blades as high speed steel will be burnt and destroyed in short order.

Teak can be glued with epoxy but it is advisable to wipe down the surfaces to be joined with acetone to remove any surface oils that will prevent proper adhesion.

When sanding teak or working in any other way that produces a lot of dust suitable extraction and personal protection in the form of a dust mask or respirator should be worn as there have been cases of workers who have been exposed to teak dust developing nasal and throat problems.

Environmental concerns

I know of a lot of folks who try to not use teak as they are concerned as to where it has been sourced and it is true that it can be very difficult to know where the material comes from. I like any other responsible user wants to but wood at a reasonable price from a well managed and sustainable source. Although one can never be certain it seems that the most reliable and trusted method is to use only wood that has been FSC certified as coming from a well managed source. The FSC or Forest Stewardship Council headquartered out of Bonn in Germany will only certify timber that is sustainably harvested and they tell me that much of the teak that finds it's way in the US comes from plantation grown forests and is thus produced in an environmentally friendly way.

 

Comments

[Ashwath]

Hi Mark

I am trying to educate myself on the application procedure of Linseed Oil and paraffin wax coating on the weather deck to preserve the teak deck. Would you kindly list out the deck preparations required before commencing the application. Secondly I would also like to know if there are any standard procedures (like industrial standards) and any references to these standards
Thanks
Ashwath

[Mark Corke]

Ashwath

Thanks for the comment but I question why you would want to put any oil on the deck. The best thing would be teak oil if any, linseed oil will not dry and it will promote mold and will be sticky in hot weather, in addition to making the teak go black. The great thing about teak is that you do not have to coat it with anything, the natural oils in the timber protect he decking as I mentioned in the story. In short I strongly caution you against using any sort of oil on your deck. As long as the wood is in good condition I would just leave it to weather naturally. There are decks that are 100 years old and still in good shape which have never been oiled. The other thing is that once you start oiling deck you will have to keep doing it thus giving yourself annual if not twice yearly uneccesary work.