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ketchgould
05-07-2013, 09:13 AM
I am attempting to keep the exterior teak bright in a few places on our 1961 sailboat. I am very frustrated with my current progress and was hoping for some tips before I strip the varnish and let it grey again.

WHAT I APPLIED AND HOW:
I sanded (220 grit) the gray and molding teak on the cockpit coamings and hatch covers and then wiped with acetone to remove oil. I then applied two coats of thinned west system with special clear hardener to build up some layers. I sanded in between coats (220 grit) and finished with 4 coats of flagship varnish.

HOW IT LOOKS AFTER 7 MONTHS OF MINNESOTA WINTER:
There are quarter sized patches of places where there is now exposed bare silver teak again. These are about 3 patches for each square foot of teak. I also have places where moisture has seemed to get behind my treatments and has formed a yellowing, cloudy space behind the finish work. These are about a square foot in size and happen every ten square feet or so of finished teak.

QUESTIONS I HAVE:
Is this just the way it goes with exterior varnish? Will I have repairs like this every year?

How do I repair what I have?

Why do I have these areas that have failed?

Is there a better product (I wont use Cetol, can't stand even the newest colors...)

How about Poly?


Thanks a lot,
Christian Gould

SchoonerRat
05-07-2013, 09:46 AM
4 coats is kind of thin for a decent UV protection, and the thinned West isn't really buying you much. You'll need to go back to bare wood again. 8 seems to be the magic number for varnish coats. Plan on scuffing and applying a refresher coat once or twice a year. You should get at least a decade before you need to wood again.

There's lots of great varnish info on the forum, but the forum search is pretty worthless. Do a Google search with this entry

varnish site:forum.woodenboat.com

Google will only give you results from the forum here.

Have fun!

BBSebens
05-07-2013, 09:51 AM
strip the varnish and let it grey again.




Not really helpful.... but varnishing teak is an uphill battle.

skaraborgcraft
05-07-2013, 02:17 PM
I have had some success with G4 poluyurethane varnish on teak, which is a damn site easier to strip off when needed than epoxy, but much harder than "ordinary" varnish. Do you object to oil? LeTonkinois is another good product that i would happily use. Depends on the required finish you want and how much maintainence you are willing to do. 12 coats of Epiphanes is what i use to apply to the teakwork on a stink pot in the Med, and refreshed twice during the summer season. Also used a lot of Deks Ole on that cruiser and was easier/faster to look after than the varnish. The owner eventually decided to go with Deks on everything except the handrails and external rub rails.

Cogeniac
05-07-2013, 04:17 PM
I have seen many posts on this topic, and I can't understand why so many people have so much trouble with teak and varnish.

First off, I would not use any sort of epoxy. Teak is wood and wood like oil and resin (AKJA varnish). You need to sand it all smooth and clean, and then start with thinned varnish. I like Epifanes, but there are many good quality REAL varnishes out there. Pick one and use it exclusively.

My process (other have their own versions, but they are all very similar):
- Thin the first couple of coats 50% with high quality brushing thinner. Let it dry thoroughly and sand with 220 between coats
- Move up to a 25% thinned mixture, and do 2 more coats. Let it dry thoroughly and sand with 320 between coats
- Move up to a 10% thinned mixture 9or whatever brushes well in your climate and on your boat), and do N more coats. Let it dry thoroughly and sand with 320 between coats.

I sand with a medium hard block using 3M Frecut paper (it doesn;t seem to clog as much as others).

Generally when N is about 2, you start seeing a good finish. When N is about 3-4 you should be pretty much done.

Then sand with 320 every 6-12 months (depending on your location and sun exposure) and ad 2 more coats at about 10% thinned. MAKOTO's entire superstructure is teak, so I have a guy come and do the annual routine (I just don't have the time or the stamina to do that much sanding, and my varnish skills are no match for his...but if you keep on it, you get a solid base and it never really peels or burns

I have seen a 2 coat varnish job burn off in 3 months, but once you have 8-10 coats on, assuming they were applied properly, they are pretty stable.


http://mv-makoto.com/makoto/IMG_2272.jpg


http://mv-makoto.com/makoto/varnish12012.jpg

I am not a fan of Cetol. To me it looks like a bad spray bottle tan, but that's just my personal opinion.

BBSebens
05-07-2013, 04:21 PM
I have seen many posts on this topic, and I can't understand why so many people have so much trouble with teak and varnish.

First off, I would not use any sort of epoxy. Teak is wood and wood like oil and resin (AKJA varnish). You need to sand it all smooth and clean, and then start with thinned varnish. I like Epifanes, but there are many good quality REAL varnishes out there. Pick one and use it exclusively.

My process (other have their own versions, but they are all very similar):
- Thin the first couple of coats 50% with high quality brushing thinner. Let it dry thoroughly and sand with 220 between coats
- Move up to a 25% thinned mixture, and do 2 more coats. Let it dry thoroughly and sand with 320 between coats
- Move up to a 10% thinned mixture 9or whatever brushes well in your climate and on your boat), and do N more coats. Let it dry thoroughly and sand with 320 between coats.

I sand with a medium hard block using 3M Frecut paper (it doesn;t seem to clog as much as others).

Generally when N is about 2, you start seeing a good finish. When N is about 3-4 you should be pretty much done.

Then sand with 320 every 6-12 months (depending on your location and sun exposure) and ad 2 more coats at about 10% thinned. MAKOTO's entire superstructure is teak, so I have a guy come and do the annual routine (I just don't have the time or the stamina to do that much sanding, and my varnish skills are no match for his...but if you keep on it, you get a solid base and it never really peels or burns

I have seen a 2 coat varnish job burn off in 3 months, but once you have 8-10 coats on, assuming they were applied properly, they are pretty stable.


http://mv-makoto.com/makoto/IMG_2272.jpg


http://mv-makoto.com/makoto/varnish12012.jpg

I am not a fan of Cetol. To me it looks like a bad spray bottle tan, but that's just my personal opinion.


Sound advice from Mr. Cover Model here....

Bad Spray Bottle Tan. Thats funny. An accurate color description.