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PostPosted: August 15th, 2009, 12:09 pm 
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Location: Freeland, Maryland USA
What is your preferred varnish(s) for canoe brightwork and paddles. And your preferred thinner and thinning schedule?


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PostPosted: August 15th, 2009, 6:15 pm 
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Epifanes is great varnish with a luxurious gloss, but at around $40/quart it is pretty pricey IMO. I get a great result with McCloskey's "Man O' War" for about half the price. My varnish work isn't yacht quality brightwork and it doesn't need to be. Man O' War is very forgiving to apply and seems quite tough, maybe just a shade less glossy than the Epifanes but with a nice rich color and sheen. Smells awesome too.

I apply a 50/50 mix of Tru-Oil (you can use boiled linseed if you want) and gum spirits of turpentine until the wood won't soak up any more and then wipe it off. It will penetrate deeply and provide an excellent ground for the varnish coats. Wait at least two days and then give it a light sanding with 220 grit.

New regs regarding VOC content have left most varnishes a bit too heavy bodied to flow out nicely out of the can. It needs to be thinned about 7-10% with odorless minerals spirits to brush properly. Never dip anything into the original can. Always pour out only what you need and never return the rest to the can, just toss it. It's a real good idea to use a disposable paint filter to filter the varnish. I rinse my filters with a little mineral spirits and reuse them a few time to save money.

As you use the varnish it gets thicker due to evaporation of the solvent. When it gets too thick it won't brush nicely anymore. Just toss it, you won't be able to figure out how much thinner to add at this point, and too much will make the varnish run. After a few coats you will figure out pretty close to how much you need and won't waste much.

Let each coat dry 24 hours and lightly sand with 320 wet-or-dry. Four to five coats minimum (yacht brightwork gets about 10), sanding between each coat. Each coat will look better and better. Switch to 400 grit before last coat. If you flub the last coat, just sand with 400 and add another, it will never hurt to add one more coat. :wink:

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PostPosted: August 15th, 2009, 10:08 pm 
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Three coats of epoxy followed by three coats of varnish... this results in a deep, glossy finish and is described here (probably a great way to sell even more epoxy for West):

http://westsystem.com/ss/varnish-over-epoxy/

They say the epoxy coats can be applied all in one day, but I've had better results by sanding between coats, waiting 24 hours. This eliminates any fuzz and dust and provides greater smoothness.

Like BK writes up above, I spoon out enough varnish for each coat into a clean cup, never using varnish from the can itself... this helps eliminate dust. Disposable foam brushes are dust-free and also help, especially in the final coats.

I used to use Interlux Schooner varnish (expensive), thinning 10% with mineral spirits to reduce runs and drips. It's a traditional urethane and tends to form fairly thick coats.

With paddles, I decided to try Defthane, a polyurethane that's supposed to be harder and more abrasion resistant. It doesn't need thinning, and it forms thinner coats than the traditional urethane spar varnishes I've tried. The thinner coats mean more coats need to be applied to get the same kind of gloss, but with epoxy underneath this is less critical. The harder surface makes it easier to sand between coats.

The Interlux Schooner varnish I used several years ago seems to be slowly darkening with sun exposure... maybe this is what they mean by "if you want that beautiful traditional look of varnish use Schooner". I don't know whether Defthane will do that since it's a newer polyurethane.

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 Post subject: Varnish dregs as oil mix
PostPosted: August 16th, 2009, 11:21 am 
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Battenkiller wrote:
As you use the varnish it gets thicker due to evaporation of the solvent. When it gets too thick it won't brush nicely anymore. Just toss it ......



When I get down to the dregs in a can of varnish I turn it into a 3-part oil mix for wood gunwales, paddle grips, poles and ect. 1/3 vanish, 1/3 boiled linseed oil and 1/3 turpentine. The first coat on something previously untreated gets a bit of added turps.

Wipe it on liberally, let it soak in a bit, wipe it down, let it dry for a day or three depending on the temperature and humidity and repeat. Three or four initial coats and an occasion refreshening makes a nice finish.


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PostPosted: August 16th, 2009, 11:34 am 
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I've found the foam brushes to have lots of dust embedded in them. Sometimes they shed a few broken down foam particles as well. I take my shop vac to them and this seems to suck all the debris out of them a lot better then flicking them or hitting the handle against the bench or whatever.

Another thing I forgot to mention is to wipe each sanded coat thoroughly with a good quality tack cloth. You'd be surprised to see what comes off the surface.

I try to varnish in a totally dust free environment. I bring the boat inside and get it set up, then I put a HD exhaust fan in the doorway and blow out the entire shop with a leaf blower. I try to corral the debris and blow it all toward the fan, making sure I get the area immediately over the boat particularly well. You can see huge clouds of dust get blown out even after several passes.

I have a large overhead dust filtering unit that I run for several hours. Then I take off my shirt and wet my arms and hair to keep the dust in place, wet the cement floor with a mop and only then do I wipe the boat down and open the can.

Seems like a lot of work, but it's becoming a routine already. End result for all this fuss?


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PostPosted: August 16th, 2009, 11:50 am 
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Mike McCrea wrote:
Battenkiller wrote:
As you use the varnish it gets thicker due to evaporation of the solvent. When it gets too thick it won't brush nicely anymore. Just toss it ......



When I get down to the dregs in a can of varnish I turn it into a 3-part oil mix for wood gunwales, paddle grips, poles and ect. 1/3 vanish, 1/3 boiled linseed oil and 1/3 turpentine. The first coat on something previously untreated gets a bit of added turps.

Wipe it on liberally, let it soak in a bit, wipe it down, let it dry for a day or three depending on the temperature and humidity and repeat. Three or four initial coats and an occasion refreshening makes a nice finish.


That's very similar to the old boatbuilder's "3-2-1" wood sealer - 3 parts turpentine, 2 parts boiled linseed and 1 part varnish. I use the Tru-Oil since I get it by the gallon for only $40. I think it has some varnish resins in it according to some posts I remember.

At any rate, whatever it has in it, it builds a nice film quickly so I don't add varnish to the mix. In fact, on paddles I never use varnish at all. One good soaking coat of the 50/50 mix and then 10-15 wipe on-wipe off coats of straight Tru-Oil makes a nice finish all by itself. But I may take your advice and save those dregs to add to the mix and play around with that. Always learning.

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 Post subject: Oil and varnish test
PostPosted: August 16th, 2009, 12:38 pm 
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Battenkiller wrote:
That's very similar to the old boatbuilder's "3-2-1" wood sealer - 3 parts turpentine, 2 parts boiled linseed and 1 part varnish. I use the Tru-Oil since I get it by the gallon for only $40. I think it has some varnish resins in it according to some posts I remember. .


If I'd known I would have incorporated those into an ongoing finish test

Last summer I got around to performing an experiment with various oil, varnish, urethane and epoxy as wood finish products.

The test: I coated sections of finish sanded ash gunwale with a variety of varnishes, urethanes, epoxies and oil treatments.

(Note: Personally I’d use oil and not varnish on wood gunwales, I just happed to have lots of sections of wood gunwale available to play with as test wood pieces)

The finish coats
Top row:
Helmsman Spar Urethane (3 coats)
Sikkens Cetol Marine (3 coats)
Sikkens Cetol Marine Lite (3 coats)
Epifanes Clear Spar (3 coats)
Epifanes Rapidclear (3 coats)
Coronado Marine Spar (3 coats)

Bottom row:
Control (no finish)
West System Epoxy (two coats)
West System with one coat Coronado varnish overtop
GunwaleGuard (3 coats + once yearly)
Oil mix (1/3 varnish, 1/3 boiled linseed, 1/3 turpentine) x 3 coats + once yearly
Watco oil (3 coats + once yearly)

http://good-times.webshots.com/album/563939478VKDdbz

All the varnishes were thinned (or not) as recommended. The labeled sections of gunwale are screwed (left over stainless screws) into a piece of vinyl siding. All the screw holes were countersunk and varnish/epoxy/oil finished inside using a pipe cleaner. The test panel is screwed vertically onto my canoe rack out in the weather in partial shade.

The test panel went up in June 2008 and I’m overdue for a reoiling of the pieces that get once yearly rub downs, but the first year results are already revealing:

Top row from worst to best:
Sikkens Cetol Marine and Sikkens Cetol Marine Lite. Not terrible, but both show a little more weathering already than any of the other varnished pieces.

Epifanes Clear Spar and Epifanes Rapidclear. Still pretty good, with just a tiny bit of weathering.

Coronado Marine Spar. A bit of a surprise as the best of the “real” varnishes.

Helmsman Spar Urethane. The real shocker. By far the most commonly available and least expensive, and by far the best so far. Straight outa the can.

Bottom row from worst to best:
West System Epoxy. I’m astounded how bad epoxy went in 14 months time without a UV protective top coat. Flaking, cracking and peeling, it looks like wood leprosy.

Gunwale Guard. Also nasty. Although all of the test pieces of scrap gunwale were dry, aged and sanded down to 400 grit the GunwaleGuard treated piece has raised wood fuzz and separating grain.

Control (no finish). Actually better than the gawful unprotected epoxy or the fuzzing GunwaleGuard.

Watco – Not as good as I thought it would be.

DIY oil mix – Marginally better than the Watco. I’m thinking the oiled pieces need more than a one-a-year light sanding and reoiling.

West System with one coat Coronado varnish. As good as any of the top row varnishes. I’m amazed at the UV protection that a single coat of varnish over epoxy affords.

It’ll be interesting to see how each finish does with more than a year’s time, and how the oil finishes do with yearly sanding and recoatings, but after 14 months exposure I’m liking Helmsman Spar Urethane, Coronado Marine Spar and epoxy resin with a UV varnish topcoat as the “plastic” protectants and the DIY oil mix of varnish/boiled linseed and turps as the oil rub.


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