Paint problem after 1st use

[Joe D.]

I finished my first restoration (a 1964 Old Town Otca 16’), and my son and I took her for her maiden voyage in the Okefenokee Swamp. Two problems developed during the trip:

The first turned out not to be too serious. During the first few minutes in the water, we heard popping and cracking noises. I immediately looked for incoming water as a large alligator along the shore eyed our journey away from the boat ramp. The noise turned out to be the cane seats giving way. Easy enough to fix. The old cane looked fine during the restoration, but turned out to have no strength.

The second problem is more serious. When I took the canoe out of water the second day, the paint in several places along the bottom had blistered. Some blisters were as large as a quarter inch filled with fluid (either dark tea color, or thick and the grey color of the filler). I have several hypotheses on the cause of the problem and would appreciate anyone’s opinion:

1) I didn’t let the paint dry long enough. The last coat went on about 2 weeks before the trip and waited at least 2 days between each of the 3 coats. I always applied coats when the temperature was above 50° F but the temperature at night in the garage often went down into the 40°’s and possibly 30°’s.

2) I didn’t let the filler dry long enough. It was put on at least 4 weeks before the first coat of paint. It seemed dry but the same low temperature conditions existed in the garage at night.

3) I used the wrong type of paint. I used Interlux Brightside Polyurethane Premium Single Part Enamel (4359 White).

4) I should have put down a primer before painting.

I plan to sand down the effected areas which will expose the filler (and lightly sand the rest of the hull), let the hull dry in the now warmer weather for at least a month, and then re-paint. Again, any help would be greatly appreciated.

Well, it’s frustrating not to be able to get the canoe back in the water again, but the whole restoration experience has been a lot of fun. In fact, I was a bit sad that I wasn’t going to be able to go down to the garage and work on the canoe anymore

 

[Larry Meyer]

Wrong paint might be the issue. "Brightside" is usually what Interlux designates a "topside" (above the waterline) paint. I would check with Interlux about whether usage under the water is recomended. I've used old-style Interlux oil based marine enamels with good results, but not a brightside polyurethane.

 

[Larry Meyer]

Interlux website is rehttp://www.yachtpaint.com/usa/

Its looks to me that Interlux doesn't make any traditional enamels that would work on a canoe any longer. I did my canoes oh eight years ago and more and I recall someone posting shortly after that that interlux was dropping the line of enamels that I used on my canoes. I went out and found a couple of quarts before they disappeared.

 

[Fitz]

Paint Blisters

Did the interior of the canoe get wet?

I've had this happen after a thorough soaking of the interior. Water penetrates the canvas and the filler and forms little bubbles of water under your nice paint job. I've seen it on boats done by pros too.

There was quite a long discussion about it on the forum before the big crash. If there are new solutions to the infamous blister problem I'd like to hear them too. For now I keep experimenting.

I find if you leave the canoe to dry right side up, the blisters dissipate.

There are a few long discussion now on the WoodenBoat Forum about blisters under topsides enamel after long exposures to water. It is a common problem. Most people use the boats and live with it.

I was wondering about trying one of those two part epoxy primers to try and beat the problem.

Good Luck.

 

[Dan Miller]

If your blisters are filled with oil, then it suggests that your filler didn't cure long enough. Rule of thumb for drying filler is 4 weeks at 70 degrees F. Longer, of course, if your temp drops below that. Composition of the filler may also affect curing time.

I don't have any experience with the paint you used. I've always used marine alkyd enamels with good results. Looks like Larry's right, Interlux isn't making 'em anymore, though you can get limited colors from Jamestown or Hamilton. So we're down to just Kirby's and Epifanes, for as long as they last. Fortunately, both are good products and have great colors...

 

[sandpiper]

Good morning. I agree with Dan Miller. I suspect the filler wasn't cured enough. There must me some linseed oil in the filler. When you sand before painting, if you see dark spots starting to show, it isn't dry enough. I use the same type of paint as you did without problems. Of course, this paint isn't mades to stay in the water over a long period of time like for a boat for instance.But for a canoe, I think there is no problem because it doesn't stay in the water for a long period of time. Often, I put a canoe in the water, only a few days after the paint job. No problem. Maybe somebody else has an other sound of bell! Have a nice day.

Sandpiper

 

[Larry Meyer]

I get modest blistering of the type described by Fitz, even with the old Interlux paint, when interior is really wet, such as when I hose it out. So maybe belay that plan to sand everything down again and wait and see. If you're looking at complete paint failure that would be one thing, but a dozen or so quarter size blisters, if they settle down again sounds paar for the course

 

[Larry Meyer]

Compatibility of a poly with your filler may be an issue. Bill Clements is about the most serious student of paints, I know, but paint formulas have changed so much lately its hard to assert there's a solid body of expereince with them. I would guess an oil based paint would work best with a filler with linseed oil in it, as the odds of bizarre chemical interactions are lower.

 

[ebeeby]

I had some blistering which was actually the canvas swelling from the inside as a result of water (from shoes etc) inside the canoe. In 1-2 days it had all vanished!

It did give me an awful scare however.

 

[Andy Hutyera]

4) I should have put down a primer before painting.

One thing I recall from the vanished thread was the advice not to use primer. I had used primer and got blistering. As in Eric's case, mine mostly disappears when the canoe dries.

Unfortuantely if you are getting linseed oil goo out of the blisters, the culprit is most likely in the filler.

 

[Gil Cramer]

After receiving a call about paint blisters along the planking lines ( fortunately,not one of my restorations), I needed to remove a plank on a canoe all ready for canvassing. I immediately noticed how much uncured varnish was on the plank edges. ( I oil and varnish BOTH the interior and the exterior of the planking before canvassing).
Since paint blisters occur fairly soon after re-canvassing, usually when the canoe is saturated inside and out, more so in acid water, and then sometimes go away, it seems to me that uncured varnish along the planking seams just might just be the cause.
Maybe the interior water washes the solvents out of the seams and into the canvas, and maybe acid water washes more solvents from the seams.