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MillstreamPocket
05-12-2015, 10:19 AM
Hi Folks, I'm new to the wooden boat world and have what may be a really dumb question. Why varnish? I have a Monhegan Island Skiff that I just oiled up for the season with 50/50 Boiled Linseed and Turpentine. It looks great, went on so easy, is simple to clean up and I really like working with it. Meanwhile I'm chipping varnish off the Cabin Sides of our other boat and wondering, why not just do the oil treatment I did on the skiff?

Can traditional brightwork be oiled rather than varnished? Is there a risk in going with oil that penetrates rather than varnish that "coats"?

Peerie Maa
05-12-2015, 11:34 AM
Varnish is better protection and does not turn black because the mould won't eat it.

Varnish slowes down the effects of changing humidity, but if you don't have to worry about that then the boat won't deteriorate with oiling.

Hreoaj
05-12-2015, 12:06 PM
Varnish generally has more UV inhibitors as well. Oil has come a long way in the solids department but quality spar varnish would be the way to go for UV protection.

MillstreamPocket
05-12-2015, 12:58 PM
Thanks to you both. Very helpful. If I go with oil and it gets black due to mould can I sand it and re-oil or is irreparable damage done?

Hreoaj
05-12-2015, 01:05 PM
Mold can be cleaned with a powdered bleach wood cleaner or mix your own with laundry bleach, water, and borax. You can google DIY ratios/recipes. Optionally you can follow up the cleaning with a wood brightener which is an acid based product. It will "brighten" the wood to a uniform lighter color when scrubbed on. Don't leave either solution on longer than ten minutes though. Sanding is also possible but bleach solutions are the best way to make sure you kill the micro organisms that grey wood.

edit:spelling

MillstreamPocket
05-12-2015, 01:17 PM
Thanks again. I have my work cut out for me.
https://millstreampocket.files.wordpress.com/2015/05/img_0309.jpg

pcford
05-12-2015, 01:18 PM
Use varnish because it is the best clear finish that you can obtain.

Also, repeated bleachings are not good for the wood.

Hreoaj
05-12-2015, 01:47 PM
Use varnish because it is the best clear finish that you can obtain.

Also, repeated bleachings are not good for the wood.

That's a good point and I should have included it. Make a test batch and apply to scrap wood for giggles. If you leave a solution of either bleach or brightener on it will break down cells and leave a fuzzy texture. As I said don't leave it on longer than ten minutes. Also rinse well. Protect things you don't want chemicals on. Or apply multiple coats or varnish when the wood is new and then sand/apply maintenance coats yearly.

pcford
05-12-2015, 01:54 PM
That's a good point and I should have included it. Make a test batch and apply to scrap wood for giggles. If you leave a solution of either bleach or brightener on it will break down cells and leave a fuzzy texture. As I said don't leave it on longer than ten minutes. Also rinse well. Protect things you don't want chemicals on. Or apply multiple coats or varnish when the wood is new and then sand/apply maintenance coats yearly.

Or just varnish. Protect from the sun and it is good for years. No need to bleach. And looks better.

Hreoaj
05-12-2015, 02:05 PM
Right. Bleach is only when you want to "restore" dis colored(grey) wood or kill black mold.

Lew Barrett
05-12-2015, 04:15 PM
Varnish looks best as well. If somebody else does the prep (a big if), I'm happy to apply varnish virtually free of charge. It's really satisfying.

Phil Y
05-12-2015, 04:19 PM
Why oil or varnish, when paint actually does last for years rather than months?

pcford
05-12-2015, 05:08 PM
Varnish looks best as well. If somebody else does the prep (a big if), I'm happy to apply varnish virtually free of charge. It's really satisfying.

You darned kids better take Lew up on that! He is pretty darned good!

WszystekPoTrochu
05-12-2015, 05:51 PM
With all "hope he has stocks in a varnish factory", "with all that varnish guests surely must take their jeans off before getting aboard" et cetera - how durable is a varnish finish, compared to paint?

Phil Y
05-12-2015, 09:39 PM
Its not. There are no good UV inhibitors available in clear. Paint has pigment, which goes a long way to stopping the UV. So varnish of one sort or another may be just as hard and scratch resistant as paint, maybe, but it breaks downfast just sitting in the sun. This just from experience. Im no paint chemist.

Gerarddm
05-12-2015, 10:19 PM
Varnish looks nice.


:-)

Todd Bradshaw
05-13-2015, 01:57 AM
There are no good UV inhibitors available in clear.

While paint does stop UV where mostly it will just chalk the surface of the coating (which can then often be polished away as long as enough of the paint film remains) there are multiple types of UV absorber additives which can, and are, used in varnishes and other clear coatings. They're not going to be as maintenance free or as UV resistant as good paint, but they continue to improve.
Interlux has a pretty good explanation of what goes into their varnishes (including UV absorbers) here:

http://www.yachtpaint.com/LiteratureCentre/How%20to%20varnish%20like%20a%20pro.pdf

This one is an example of a company currently making UV resistant additives.

http://www.ashland.com/Ashland/Static/Documents/ASI/Paints%20and%20Coatings/PDS_5014-E_SunCare_TopCoat_Europe.pdf

In any case from what I've seen, the most critical factor to the lifespan of either type of finish (or even an oil finish) is limiting the ability of water to get into the wood through cracks, open joints or damaged areas where it can get under the finish and lift it. In cases of peeling paint or varnish, or weathering wood, that's the first place I'd look.

phiil
05-13-2015, 06:19 AM
When you bump into another boat, a varnished rubrail will leave no mark; a painted one will leave traceable evidence.

Tom Hunter
05-13-2015, 06:31 AM
Remember you asked why varnish, so people are answering that. There are good reasons to oil too. I'm a varnish guy, so I don't know what they are, but someone may come along and tell us.

Ian McColgin
05-13-2015, 06:36 AM
If you actually want to do a good job with oil, use neatsfoot oil in the mix, not linseed. It's that simple. If you want what works like oil, costs only a little more in the end, and does not blacken, use the Deks Olje #1 and just keep adding.

Peerie Maa
05-13-2015, 06:37 AM
Remember you asked why varnish, so people are answering that. There are good reasons to oil too. I'm a varnish guy, so I don't know what they are, but someone may come along and tell us.oiling requires no skill whatsoever. You get back in proportion to what you put in.

willin woodworks
05-13-2015, 12:34 PM
Neatsfoot instead of linseed? Really? Never heard that before.
Love trying something new...Thanks Ian.

Peerie Maa
05-13-2015, 12:43 PM
If you actually want to do a good job with oil, use neatsfoot oil in the mix, not linseed. It's that simple. If you want what works like oil, costs only a little more in the end, and does not blacken, use the Deks Olje #1 and just keep adding.

I tried Deks Olje #1. It did not blacken, but the wood (larch) did bleach in the weather. It probably does need topped off with Deks Olje #2

Lew Barrett
05-13-2015, 02:44 PM
You pick your coating according to the job at hand. Some boats can benefit from the use of all the available options; varnish, oil and paint. This boat used all three approaches where I deemed them appropriate, which was exactly what the "builder" also specified by the way. I know the builder (nice guy) so it was easy to ask him how he finished them.

Hvalsoe spec'd Seafin to me, a product I was already familiar with, for the interior and a good quality spar varnish for rails, thwarts, stem, transom etc. Made perfect sense to me, so that's how I finished her. Runabouts get varnish. Yachts, mostly paint and varnish. Work boats, whatever!


http://i240.photobucket.com/albums/ff76/LewBarrett/Hvalsoe6.jpg
http://i240.photobucket.com/albums/ff76/LewBarrett/trailer3.jpg



It's not that complex. Horses for courses.



The benefit of oil, apart from Nick's inference that it is less labor intensive, is that it usually allows better footing (decks) and it will often accept paint or varnish (sort of depends on what you put down) without a lot of pain if you change your mind. Generally the least durable finish, it's also the easiest to refresh.
Sometimes it's an ideal finish. I'm thinking things like the interior of certain open lapstrake boats where varnish (or paint) would be hard to apply and difficult to prep for, but as a rule, I'm a varnish and paint guy myself.

Daly's makes Seafin and I believe Eric still uses it as I did when I refurbished his No. 6. Excellent product that dries relatively hard, is easy to apply, and looks great on good woods. But it doesn't replace varnish when varnish is called for.

Thorne
05-13-2015, 05:45 PM
I think Lew's got the winning combo for small open boats.

Oil (aka Boat Soup) works well in cold, misty, wet climates. In hot sunny areas it can mold and certainly will get sticky and muddy.

Remember that there are many types of varnish, with the spectrum ranging from old-school mixes like Le Tonk through harder products and ending with nearly-artificial high-end stuff.

Bobcat
05-13-2015, 05:59 PM
Would you use Seafin on a teak deck?

Lew Barrett
05-13-2015, 07:57 PM
Would you use Seafin on a teak deck?

Fair question, longish answer (just thinking out loud here).

And now, why you'd oil a teak deck......... :)

If you wanted a somewhat finished look, or if you wanted to protect the deck from weathering without going to the trouble of varnishing them, assuming you didn't care for them in traditional fashion. Maybe it's not practical in some situations (Lake Union?) to give teak decks gentle sea water baths, and teak will weather if just left untended in the sun. It's still wood and it will wear. Much more likely, you would use it on something like fir, so frequently found on decks up here, especially older boats. That would be in case you wanted some protection but didn't care to go to varnish. And it was that sort of decking I was thinking of.

Of course, a properly tended bare teak deck will silver and look terrific with varnished king planks, but just because it's terrific decking material doesn't mean it will always be maintenance free.

There are lots of ways to skin the cat and if any of my boats ever afforded me the luxury of a great teak deck properly laid and in good condition, no doubt I'd leave them to gently weather, carefully washing them down and very gentle "brooming" them off ( I don't have a word between caressing and scrubbing to use here) to maintain them in their natural state without running deep grooves into their silvered loveliness. All decks look like crap after a summer's worth of barbequing, and will end up being oiled in that case anyway!

Yes, you could use it on a teak deck if your particular conditions made sense. On a fresh deck, it seems to me it would be extra work without much benefit. To even out the color of a deck on the way out, or to protect what's left of a teak deck that has seen better days but might still be serviceable, maybe worth a try.
I don't see using it on a clean, fresh deck except maybe in a cockpit where you know the thing is going to see a lot of wear, dropped salads, spilled drinks and fallen pork chops.