Varnish in winter?

[dmooch]

Hi folks, a newbie here...
Live in the northeast, cold! I have been told by an old salty dog of a captain that I can successfully strip my teak on the Grand Banks, do my sanding to prep the wood and then apply the varnish during the winter month (outdoor storage). Any thoughts on doing this kind of work during winter months?
If so, what have you found as the most durable products in this kind of situation?
I was told that I could cut the first few coats 70/30v, 50/50v, 25/75v..then straight varnish. Of course i would have to warm up the varnish in the microwave for a few seconds...Do you think someone is puling my leg?
Thanks for any comments.

 

[Comodave]

I work on my boat all winter also. I do the stripping and prep work throughout the winter and then do the final work after it starts to warm up in the spring. I was just talking to Interlux support about painting in colder temps and they said not under 50 degrees. I would be leary of doing it in the cold because I would not want to redo all the work.

 

[Giggitoni]

If you lived in Long Beach, Calfornia you could pick a warm day in Winter and get away with it. I wouldn’t varnish below 65*F. Besides the low temperature, you’ll encounter more water in colder air; one of the enemies of a successful varnish job.

 

[Cigatoo]

I have a friend (here in RI) maintains classic boats. He varnishes well down in to the 40’s. The varnish takes much longer to dry but has more time to flow and level out. He does beautiful/ professional work.
Of course the longer that it is wet the more time it can collect sh**. So a covered area is nice. But it is defiantly doable. He uses Epifanes. Not sure that I would put it in the microwave. Buy certainly keep it in a heated area until ready to use.

 

[sunchaser]

50 F no problem but in the PNW dew the norm so don't wait until late afternoon to apply varnish. Can't go wrong by following the can guides. Long Beach CA should seldom prove daytime problematic, even in the "winter"

 

[RT Firefly]

Greetings,
Mr. d. If your boat is in the NE, why take any chances? Wait until you get warm enough weather in the spring. I think I'm safe in saying you've got other chores that can be done in the mean time.

I wouldn't put anything in a microwave that is flammable unless your prepared to make a U-Tube video.

 

[Maerin]

I've applied Epifanes in the 40's, in fact there was frost on the surfaces in the morning. Once the sun comes up and it starts to warm, not an issue. Keeping hands limber is a problem, and the varnish is VERY slow to dry, I used Epifanes accelerator to get it to dry between coats. No impact on the cured appearance. As long as the surface is dry before it starts cooling off in the afternoon there's no problem with bloom. I'd wet sand 1st thing in the morning, then clean with denatured alcohol prior to coating. I prefer alcohol to mineral spirits or acetone, it seems to evaporate more completely. The cold weather is great for getting it to float nicely, you can get more material on, and NO bugs! Other than slow drying, it's entirely possible do varnish in cold weather. I'll take that over hot or windy ANY day! Wind is a sure recipe for a crappy coat. Just don't.

 

[Larry M]

Could pick a somewhat warm period of the day and add some Japan Dryer to accelerate the drying?

 

[kchace]

As long as its not a water based varnish and the temps are at least in the 40's it should be all right, but I agree with RT, why take the risk?


As far as warming in the microwave goes (If there's no sparks and it doesn't catch fire), that might help the varnish be at the right consistency in the pot, but once applied in the thin layer on the wood, it will cool to the ambient temps in seconds.


Ken

 

[Maerin]

As long as its not a water based varnish and the temps are at least in the 40's it should be all right, but I agree with RT, why take the risk?


As far as warming in the microwave goes (If there's no sparks and it doesn't catch fire), that might help the varnish be at the right consistency in the pot, but once applied in the thin layer on the wood, it will cool to the ambient temps in seconds.


Ken

The other consideration is that warmer varnish will flash off the solvents quicker, so while it will initially float out a little better, it will fire off as it's floating, with the net result that it inhibits the process and can end up with a more irregular surface. That's why varnishing in the wind is so horrible. The wind accelerates the solvent dissipation, so it's just about impossible to achieve a smooth finish.

Varnishing is about putting material on the surface. It's NOT about brushing! Quality of the coat is inversely proportional to the amount of brushing! Coat it and LEAVE IT ALONE! The more you monkey with it, the worse the outcome. The smoothness of the coat is a function of the varnish as it levels out. The longer the varnish has to level / float, the smoother the surface will be. Good technique involves being able to get as much material on the surface as evenly and quickly as possible. Too thick? Thin it a bit. For Epifanes, use THEIR thinner, no Penetrol, no box store spririts. For whatever reason, the proprietary thinner makes a BIG difference. Always strain the product.

Cold weather is slow motion. Even keeping the surface covered so it won't solar warm is helpful; a lint-free, dust-free drop cloth removed just prior to coating keeps the work cooler so the varnish goes longer before it fires off.
The devil IS in the details.

 

[angus99]

Hope this is close enough to be on-topic: winter or summer, how many of you use CPES or other epoxy before varnishing?

 

[Shrew]

Ultimately, I would apply in accordance with the application instructions from the manufacturer of the product. Even if you CAN get down into the low 40F, if the can reads no lower than 50F, then I won't go lower than 50F.

 

[bayview]

As temperature rises humidity falls so do it in the morning after dew dries. Put the varnish container in a pan of warm water if you want it warmer. Pros don't work out of the varnish can.

 

[Bkay]

I agree with Shrew and I've slung some varnish in my time (not particularly great work mind you, but I've been satisfied with the results). Most of the varnish I have says 50 degree and I do my best to stay above that. Remember, that is surface temperature, not air temperature. I usually shoot the surface with a laser thermometer. Sometimes that means I can do one side and have to wait until the other side gets sun and heats up.

I would recommend heating water in a microwave and letting the can warm in the water rather than heating varnish in a microwave. Alternatively, I keep the varnish in my house overnight so it's not at air temperature. Regarding thinning, I follow the guidance I got from guys at Jamestown and cut my first coat 50:50 then go 100:0 for 8 subsequent coats.

I've had very good luck with those procedures. Good luck.

 

[senangsekali]

I am varnishing now in the pnw. You Just have to watch the dew point. If the outside temp and dew point are 4 or 5 °C apart and weather is good ie no wind and the wood is prepped and dry go ahead and try a small project and see how it turns out. The dew point is key imo.

 

[senangsekali]

Just keep the varnish inside a warm area. No need to microwave it. If you are really concerned, use a heat gun around the can for a while.

 

[Aft Deck Capt]

Hope this is close enough to be on-topic: winter or summer, how many of you use CPES or other epoxy before varnishing?

Angus, I chose laminating epoxy (2 coats) as a base under all of the teak that I've touched on our boat - no regrets. I'm convinced that it seals the wood better than varnish alone plus you get that 10 coat depth of look at 4 or 5 coats.


As to the thread topic, I would be real leery of varnishing below 50 myself. I've experienced varnish blushing in the summer once when I got greedy and laid a "last" coat to late in the afternoon. It was very warm but humid and the dew point was crossed before the varnish cured.... very disappointing.

 

[Insequent]

If humidity is a concern you could try Awlwood. It uses moisture in the air to cure. Because of this you cannot return what you don't apply to the main container - you will start the whole lot curing!

Yards love it because you can do multiple coats in a day. It seems to be very durable in our climate (high UV, akin to Florida) but I've not used it for two reasons. One is that my local chandleries don't stock it. Second is that you need some skill to apply - no over-brushing etc.

 

[ronbo]

Awlwood does indeed cure faster the higher the humidity but it needs relatively high temps to cure in a reasonable time.

 

[Lou_tribal]

Epoxy under varnish does not bring anything that more varnish can't provide. Most of wood damage is not done by moisture in the air but by UV and epoxy does not protect against UV, more than that epoxy is damaged by UV so you will need serious varnish coating to protect epoxy or later serious work to remove the damaged epoxy. So you can use epoxy and varnish 5 layers above it or varnish 8 layers without epoxy. Considering the cost of epoxy, the hassle of applying it etc I would just go with straight spar varnish that is made in purpose of protecting wood and being flexible enough to tolerate wood movements.

I love epoxy but where it brings value like structural reinforcement with fiberglass, used for gluing or seal against water (not sunlight).

L

 

[Nomad Willy]

I’m with ya Lou,
I tried several newish finishes but never epoxy. I like to get the oils in varnish down in the wood as far as possible. According to Culler, one of the foremost authorities on wood boats kerosene will “drive the finish down” into the wood better than anything else. I use it for the first 3 or 4 coats.

But even good varnish requires a coat or two every year or two.

 

[Exctyengr]

I concur with the admonitions not to heat varnish in the microwave. I bought a $5.00 mini-crock pot at the thrift store for that specific purpose. (Just don't use it for food afterward, heh, heh).

 

[Exctyengr]

There are probably as many techniques on varnishing as there are responders to this query. CPES or no CPES, Epiphanes vs everything else, etc. My go-to technique if the wood is bare (wooded down) is: (1) final sanding up to 220, (2) one or two coats of teak oil, (3) two coats of sanding sealer (shellac), (4) 7 coats varnish (I prefer Interlux Schooner or Total Boat Gleam, I have used Epiphanes but find it quite viscous and slower drying). Each coat is sanded lightly using red or gray scotch brite. When finished, let it cure for several days then I might wet sand with 400 and polish (see wooden boat #242 pg 98 for a discussion). I always strain into a clean container, I always vacuum and then tack and I always wait for good weather and no, I don't try to varnish if the temp is below 50F. Overkill, perhaps but that's what I did on my wooden boats and that's how I finish today.

 

[Lou_tribal]

There are probably as many techniques on varnishing as there are responders to this query. CPES or no CPES, Epiphanes vs everything else, etc. My go-to technique if the wood is bare (wooded down) is: (1) final sanding up to 220, (2) one or two coats of teak oil, (3) two coats of sanding sealer (shellac), (4) 7 coats varnish (I prefer Interlux Schooner or Total Boat Gleam, I have used Epiphanes but find it quite viscous and slower drying). Each coat is sanded lightly using red or gray scotch brite. When finished, let it cure for several days then I might wet sand with 400 and polish (see wooden boat #242 pg 98 for a discussion). I always strain into a clean container, I always vacuum and then tack and I always wait for good weather and no, I don't try to varnish if the temp is below 50F. Overkill, perhaps but that's what I did on my wooden boats and that's how I finish today.

Some comment on this:
1. Teak oil does no exist, there is no harvested teak pressed to make oil This is only a product label (read snake oil) sold at different price that is "in fine" nothing else than some mineral oil, linseed oil, wiping varnish and so on.
2. If you use shellac under your varnish be sure it is dewaxed shellac as if not varnish will not bond.

L

 

[Lepke]

A new (to me) product is Sun Shield. I've got a test going covering West Systems super clear epoxy. About a year old, in constant PNW sun and still holding up.

 

[ghost]

Ive always used Daly’s teak oil Before varnishing. It really exists, you can buy it, apply it and everything. I’ve never seen snakes come out of the can. It provides a nice color and penetrates better than varnish for the first coat. Teak oils are typically a varnish like concoction, incorporating drying oils (oils that cross link and cure, such as tung oil or sometimes linseed) but without a resin component to make it build like an actual varnish. Yet they provide a chemical base that is varnish friendly. Name wise, It’s kind of like the way we label chicken seed, even though you can’t grow chickens from it.

For my Myrtlewood door I built last year, I used CPES, followed by silver tip epoxy and finally a couple coats of Epifanes, I used epoxy as the Myrtle is not known as a naturally weather resistant wood. Ask me in a couple years whether I like the combination, but so far so good.

 

[Xsbank]

CPES on clean, wooded teak penetrates well into the wood and you should apply your first coat of varnish before it is cured. It apparently penetrates really well and bonds very well to the varnish. I do not personally use CPES any more as I have no exterior wood but I have interior wood; I use Le Tonkinoise which is actually gradually drawn into the wood. It has no solvents and therefore builds faster than Epifanes or other "varnishes."

Two people have stated: "the humidity goes down as the temperature warms up." You may want to check your physics textbook, I know what you are trying to say but that's not it!

I met someone who varnished everything on his boat with his hands! He heated the varnish on the stove and applied it with nice warm hands. His results were excellent but I never witnessed it.