Varnish Failures?

[drift montana]

Is there such a thing as a "bad can of varnish"? This weekend I had the first failure I've had with Interlux Schooner varnish. Applied the first coat on the inside of the Melonseed I am building on Thursdsay. I was planning on hitting it with sandpaper and a second coat yesterday, only to discover that the varnish was behaving very strangely. About 50% of the boat looked great. Nice layer that cured to a nice hard finish. The rest had a mix of splotches and other areas where it was still tacky and rubbery. Impossible to sand without gumming up. No pattern or reason to where it failed and where it didn't. Prep was the same as I've always done. Underlying epoxy is months old. Whiped clean of any stray oils, dust, etc. So I spent the afternoon scraping.

So did I get a can of bad varnish? Thoughts? Though I am not looking to open the whole "which varnish is best" debate. Seems that one has been hit hard.

Cheers!

-T

[ron ll]

Has the can of varnish ever been subjected to freezing temps? Was it a new can?

[drift montana]

New can, and the only freezing might have come from shipping. I've used this technique for 2 other boats, plus refinishing with no problems.

-T

[Lew Barrett]

Since some of it behaved normally, and some didn't, is there any chance your surfaces had anything to do with it. Say some silicone on the wood, or something to that effect.

[BETTY-B]

Is it outside? Or in a controlled environment?

DAN

[drift montana]

This is about as controlled an environment as I can get it. Inside shop. About 65 degrees. I can't think of any contamination that would have gotten on the boat. I wipe clean with alcohol and cheese cloth to get most of the sanding dust. Let dry. Wipe with Interlux brushing thinner 333, as per instructions. Then lay down the varnish. I thought it might be happening where it was on too thick, and thus taking a while to cure. But there are some places where it is very thick and it cured beautifully. Other areas are on very thin and they didn't cure at all. Most of the epoxy has had 2-3 months to cure and outgas. The only newer epoxy, 2-3 weeks old is just at the glue joints for the deck frames. But that is not where it is failing. The only changes to my standard process have been using West System epoxy, instead of RAKA. And using Mirka Gold sandpaper, instead of 3M Gold. All very puzzling.

-Tony

[Wild Wassa]

The problem sounds like one of three things but possibly all three.

Varnish needs to be well stirred, so that the oil is well blended into the medium. I stir varnish for 4-5 minutes minimum and stir it intermittently as you paint, if you are slow when painting. It doesn't take long for the oil base to come to the surface again.

Overstroking oil based paints is a no-no (and you will know whether you did). Overstroking brings the binder (the oil) to the top which inhibits the paint from setting uniformly. Use as few strokes as possible, to lay the varnish.

Apply the varnish thinly, both in thickness and in the dilution of the medium. Many thin thinned coats, are better than a few thick unthinned coats. Thick coats or thick varnish from a build-up in places can take days or even weeks to set and then harden.

Warren.

[StevenBauer]

Did you wash the amine blush off the epoxy with some clean water and a scrubbie? That could cause your symptoms.


Steven

[drift montana]

Warren-
I'll keep your suggestions in mind with the next round. I do tend to work in small batches to try and keep the stuff in my pot fresh. I'll bump up my standards.

Steven-
Yup. I'm no blushing fool. With Montana's low humidity, it has never been an issue, though I still pay attention and do my due dilligence.

Cheers! Time to make some sawdust!

-T

[Jay Greer]

One question is, did you bleach with oxolic acid?
Jay

[Concordia...41]

I vote with Lew for surface contamination.

It's a story I've told before, but I try not to ever EVER allow anything in the WD40 / PB Blaster / SailKote family to be sprayed.

SailorDave was here and working on the corroded hinges and he's standing in the middle of the warehouse with the can of PB Blaster in his hand, and I'm like - "ah... don't you want to go out in the parking lot and spray that"

Why? Because something in WD40 gives me a pounding headache, and I've gotten that headache when someone was working on my car in the garage and I was in the kitchen some 40' and two rooms away...

So if that far away I'm getting enough of a whiff to get a headache, I promise it's landing on every horizontal surface! :eek:

And if you're thinking you didn't just spray something, consider the fact that you could have sprayed something on the work bench earlier and then recently dusted off some paint cans or shook out a tarp and ta da! Little molecules (well, molecules would be little ;)) of whatever flavor contaminant are now flying through your shop looking for a perfectly prepped piece of wood to land on. ;)

Paranoid yet? ;)

Good. :)

[Lew Barrett]

Hoorah! I'm in great company:D I got the hottie on my side:D

[S B]

Yes, there most certainly is such thing as a bad can of varnish, but the whole can is like it. I don't know what happened to your can, but if a guess is any help I would say it livered,part of the compound set on its own and separated from the rest. Cause ? may be contamination from the paint stick,brush, roller,etc. any cobalt, manganese ,lead compound could do it, along with a few hundred I know nothing about.

[drift montana]

Thanks everyone. I scraped, scrubbed, vacuumed, whiped, cleaned and just laid down a thinned coat. I'm out of town for a couple of days, so it will have a chance to do its thing without me checking every two hours.

Update on Thursday. Fingers crossed.....

-T

[Jay Greer]

I will tell you that, while I have been applying varnish for over fifty years, I have yet to find a bad can or batch!
Jay

[pcford]

I will tell you that, while I have been applying varnish for over fifty years, I have yet to find a bad can or batch!
Jay

Well, I've only been varnishing boats for 35 years. In that time varnishes have come in and out of fashion.

In the middle to late 70s some used Behr Rawhide....a soft no sand finish. As far as I can recall, I have never heard anyone sing the praises of Behr varnish. Except one person...on this forum.

If it is such a superior product, why isn't known and used more broadly? And I know some of the best brush people in the NW.

The strange frenzy on this forum regarding Behr varnish reminds me of medieval tales...abelard and heloise...wherein something which is not obtainable becomes ever the more attractive.

In any event, preparation is a much more important element in an excellent varnish job than the varnish itself. To imply that Behr is the only varnish to use is to send inexperienced people on an unnecessary wild goose chase.

In my humble opinion.

But the Behr varnish story is clearly more exciting to the congregation assembled here.

[Lew Barrett]

I like it thick and goopy, then you can thin it as you will for conditions.

I've never had a bad can either, but I've had bad results. I've varnished too late in the day. I've varnished when it was too cold. I've varnished on days that were too windy, when the light was poor, or I was too tired to do the job right. To this day I can still screw up a patch with the worst of them. The beauty of varnish is that you just sand off the scabs, grit and drool lines and do it again. Nobody ever knows what a clutz one is capable of being! In the sunlight, a halfway decent job is dazzling, and even a great one will wear off in a few months or a year and require refreshment! Oh the humanity!

[Jay Greer]

Well, I've only been varnishing boats for 35 years. In that time varnishes have come in and out of fashion.

In the middle to late 70s some used Behr Rawhide....a soft no sand finish. As far as I can recall, I have never heard anyone sing the praises of Behr varnish. Except one person...on this forum.

If it is such a superior product, why isn't known and used more broadly? And I know some of the best brush people in the NW.

The strange frenzy on this forum regarding Behr varnish reminds me of medieval tales...abelard and heloise...wherein something which is not obtainable becomes ever the more attractive.



In any event, preparation is a much more important element in an excellent varnish job than the varnish itself. To imply that Behr is the only varnish to use is to send inexperienced people on an unnecessary wild goose chase.

In my humble opinion.

But the Behr varnish story is clearly more exciting to the congregation assembled here.

Actually it was quite popular at one time. But the same varnish was sold under another name. "Wilbo Spar Varnish" was marketed by the Wilmington Boat Works of San Pedro CA. and was the top commercial standard in California for many years. The name has changed but the varnish is the same pure natural oil and natural resin product it has always been. One has to know that the Crowel family who started making Behr Paint products back in the late 1940's started like Starbucks and Bill Gates on a shoesting making paint and varnish in their garage. The family did not concern itself with vast marketing schemes and was satisfied to market their products on a small scale in local paint stores. They preferred to place good quality into their wares and depend on word of mouth rather than in fancy cans or hucksterisim. When the senior member of the family passed on, a decision was made to sell the company and its formulae. Now based in Huntington Beach California, the Behr Company is a darn site larger than the original entity. Unfortunately EPA restrictions place a constraint on marketing their varnish and forces them to market in other states under the name "True Tone". Although I have attempted to convince the corporate members that they have one of the best marine varnishes on the market, they consider house oriented products to be more lucerative and so have not persued the marine market.
Jay

[Paul Stohlman]

I'll second the amine blush idea. (Other contamination running close behind.)

If you have sanded without scrubbing off the blush, it is ground into the surface and harder to remove.

There are several blush free epoxy products.

G'luck

[Jonas]

I've had the same result using Interlux Schooner over West System epoxy. Similar cure time for the epoxy that you described, and similar surface prep and temperature. I figured that I didn't scrub the amine blush sufficiently before sanding. I stripped the sticky varnish with varnish remover, and am considering my next move.

[drift montana]

Time for an update on this challenge. I tried scraping and cleaning up the areas that were giving me problems. This helped, but did not solve the problem. So Saturday was spent with stripping compound, plastic scrapers and pads. Lots of cleanup. The process revealed something interesting. Everywhere I was having varnish issues resulted in exposed glass cloth after cleaning up! This tells me that I had some bad epoxy (uncured, poorly mixed, wrong ratio?) from either the layup or the flow coats. Hopefully the stripping and extra attention to the problem areas fixed the problem. I added a new flow coat last night and am hopefully moving forward. The only real bummer is that the exposed cloth did not become transparant with the new flow coat. As my associate says, "She now has birth marks." Onward.....

On the positive side, I poured the lead for the dagger board and rudder, laminated the db and rudder, shaped the db, bunged about 100 holes, shaped the transom, mounted the gudgeons, and fit the cockpit trim!

Cheers!

-Tony

-T

[RichardH]

Ron II mentioned freezing temps as a problem. I wasn't aware that freezing damaged varnish? I store my opened quart in the freezer to prevent oxidation and surface skinning. ??

[Lew Barrett]

I've kept covered (plastic wrap or supplied cover) varnish pots in the refrigerator, but not a freezer. Varnish won't cure below about 40-45 degrees F, so a can (or brushes) left in the reefer overnight will barely change state. Freezing sounds like a bad idea though I couldn't say why. Most cans include a stricture to not store below freezing.

[calvin]

On the subject of varnish and almost everything oil based I have been thinning with turpentine and penetrol instead of so called premium paint thinners..lately..seems the old standby is still the best!

[Penokee]

I had a can of Epifanes varnish (the traditional gloss) that had been stored in a shed over winter. I called Epifanes to ask if freezing would affect or compromise the varnish and they said no. They also noted that they ship their varnish in winter in un-heated trucks.

FWIW,
Penokee