Teak - Why not polyurethane?

[s/v Copacetic]

For the first time I have a boat with some exterior teak. I keep asking myself why everyone seems to have an annual ritual of sanding and varnishing. Why doesn't anyone use a good polyurethane? It seems that would hold up to weather better.

Or maybe you do, and I've just been reading the wrong things.

[s/v necessity]

   There are some good two part finishes out there.  And they do hold up much better.  Interlux makes a clear version of their perfection (so I have been told), Signature makes "honey teak", and  there is another called  "Bristol finish"  Both Bristol and Honey teak have a tone or pigment mixed into the finish (something I do not like, I hate Cetol.  Ick!)  Each has a different look.  I think all three finishes are somewhat similar (I'm sure the manufactures would argue vigorously against this assessment though)   I am going to try Interluxe's clear when the time comes. 
    I hear that coating your teak with epoxy and then many layers of varnish holds up well also.  The downside to any of these more durable approaches is that when the time comes to go back to bare wood, it's going to be more work.  Also if using one of these finishes you will probably want to put more time and effort into the prep process.  For example the proprietor of of the signature finish will absolutely insist that you use his teak cleaner$$$ (although I know someone who refuses to....) 

   So there are downsides: More prep work, more $$ spent initially, and in the future a LOT more PITA to deal with when it fails.  From what I can tell it's worth it though.

    Don't use a finish that isn't specifically designed for the marine environment.  If you bought a can of "polyurethane" for standard furniture use it wouldn't last a week outside in the elements.... 

    All that being said another reason for this "annual ritual" is that if you wait for the finish to start failing you will have alot more work on your hands.  Sanding and putting a fresh coat of whatever finish you are using on *before* the existing finish fails, is the way to go.
   

[AdriftAtSea]

very few wood finishes do well in a marine environment. Most of the polyurethanes will do very poorly.

[CharlieJ]

We've done several things. First, let me point out that we have Mahogany above decks, not teak, but the results are about the same.

We began using Z-SPar 2015 Spar Varnish. It holds up well, but has to be lightly sanded and re-coated probably twice a year, here in our Texas sun. This after epoxy coating and then 5- 7 coats of varnish. Not a big job IF you get to it before it begins to fail. Meaning when it still looks pretty good, but has dulled a bit. A light once over with 220 or finer, and a recoat- Takes half a day.

On our wooden mast and boom, the Z-spar failed after several years where it was exposed to the afternoon sun day after day. But the other side still looked fairly good.

Laura then wooded the mast and put on 5 coats of Bristol Finish.The beauty of Bristol is that you can shoot multiple coats in one day. She shot 4 coats, with no sanding on day one, then sanded and shot a top coat the next day- Yes- she sprayed it. Bristol costs about 50 bucks a quart (took two quarts for the mast), which isn't that much more than a good spar varnish. That held up extremely well for two + years, but again, on the western side, there were some small checks appearing, that needed work. After some discussion about just repairing the damage from the bosun''s chair, Laura decided that since we planned to go out cruising and might be gone for quite a while, she'd refinish the entire mast again.

We lowered the mast, she stripped the hardware, then the finish, sanded, laid on three coats of epoxy, sanded between, then shot 4 coats of automotive acrylic clear coat- the same stuff they use on cars. We had corresponded with people who had gotten 3 or 4 years service from that, so we're trying it.The mast looks fantastic. Again- it's about 60 bucks a quart and required 2 quarts.

You can shoot the next coat of this stuff after ten minutes- no sanding.

So that's where we are now- we'll see in a few years how it did.

But Laura has settled on the Bristol for the wood work on deck, other than the toe rails- those we just oil. The Bristol has really done a good job and the coast is within reason for what you get.Cheaper in the long run than spar varnish at 35 a quart.

I (And Laura) HATE Cetol also. Looks like orange mud to us.

Have heard good reports on Epifanes, but never used it so can't comment.

Here's a few shots of the newly re-finished mast-That's Laura geared up and spraying

[s/v necessity]

Charlie,
    I have a can of Bristol that was opened and inspected.  It had a definite orange tint, and my significant other quickly denounced it as "clown finish" much like Cetol....   I muttered something about not being all that opaque and it might look different after it's on some wood and cured.  But she had enough negativity towards it's color that we shelved it and decided to find a truly clear 2 part finish.   Did you find that it imparted much color in the finishing process?  I don't mind a mild light tint that brings all the various woodwork together.  But If I remember correctly this seemed somewhat milky and yellow.  Does it change as it cures, or is it just less noticeable in a thin film?  I felt compelled to give it a shot even though SWMBO gave it two thumbs down.  (of course I had just managed to get into some sort of bizarre altercation with the owner of Signature finish the week before, so I was desperate to find an alternative two part finish that was supposedly formulated for use with wood.)

    You can just tell me the stuff is junk if you wish, I've got a can I'll sell you real cheap ;)

[CharlieJ]

That color because it imparts the standard amber tint to wood. Most people ( and I've got 28 years experience refinishing furniture :D) DON"T like a truly clear finish- it doesn't give that nice glow they are used to.

And yes, the milkiness goes away when it cures.

We think it's good stuff, and Laura plans to keep using it on all brightwork except the mast.


Oh and standard polyurethane just doesn't do well under constant exposure to the sun. Fails horribly.


Here's that same mast with Bristol on it, rather than the clear coat. And yeah- same lady spraying- I work on other peoples boats- she works on ours ;D

[CharlieJ]

one more picture

[AdriftAtSea]

The other reason I don't like woodwork, especially brightwork, is I can't keep it up to the standards that Charlie and Laura set... :)

[CharlieJ]

Leave me out of that- LAURA does the bulk of that work. Myself, I can't even come close to her level, except with a spray gun.. She does it with brushes too.

[Mario G]

I've just drown my teak with teak oil and it looks great  and seems to hold up to the  high 80*s  sun baking temps we have had over the last few weeks.

http://good-times.webshots.com/photo/2092018520101866121mDmXpo

All the outer teak on my Chrysler C-22 was very questionable when I first got it but after a half a dozen applications I really like the look and don't mind doing it. In fact I'm looking to add as much teak as I can.

[AdriftAtSea]

Leave me out of that- LAURA does the bulk of that work. Myself, I can't even come close to her level, except with a spray gun.. She does it with brushes too.

lol...  yes, but at least you have laura to do that... :D