[kelly]

I now see it all. Thank you Downriver Tackle for sharing your knowledge. Nice site to!

[mark poulson]

Downriver,
Do you have any experience with Minwax Wood Hardener? I used it for the first time as a sealer on a wooden lure, and the lure cracked when I left it in the heat.
I used Krylon white primer over it, then Auto Aire water based aluminum, opaque water based Createx, water based Wildlife Colors iridescent violet, Krylon spray glitter, Krylon spray clear with UV inhibiters, and then two coats of Etex.
The top of the head split and peeled, down to the primer, which seems tacky.
I wonder if the sealer and primer didn't bond, or if the sealer still had solvents left in it.
The Wood Hardener is some kind of a polymer that restores rotten wood to structurally sound.
Looks like I'll be stripping and redoing at least the head of that lure.
And I guess I'll have to put the rest of them in the garage between trips, to keep them from getting too hot.

[Downriver Tackle]

No, I haven't used that before.

That aluminum would be my first suspect. I t takes a long time to dry and properly cure. That's happened to me. Something in that combo didn't cure correctly or you had a really hard paint up against a softer paint. I try to use Autoair all the way through the colors. They've already done all the r&d work and know they're paint works together in a system. When I'm using that many layers also, I make absolutely x-tra sure everything is fully cured before I clear it.

[mark poulson]

Downriver,
I examined the lure under sunlight, and it really looks like something in the paint scheme bubbled on the top of the head under the 110+ degree heat under my boat cover, and caused the epoxy to bubble and crack.
The white Krylon primer is what's left under the peeled section, so I think either it was too thick, and not fully cured, or the opaque black that went over it wasn't fully dried, so water vapor developed, causing a bubble and cracking. The Auto Aire alum was put on the belly and lower sides, and then the black went over the middle and upper sides and back. Then I put the auto air over the sides and shoulders as a scale pattern. The paint scheme come off with the Etex Lite epoxy, all the way down to the primer which is still on the lure.
Anyway, I'm going to redo the front section (gotta love removable pin hinges) and repaint it the same way, only drying it better between coats.
And I'm taking my lures off after I fish them, and putting them in the garage, instead of baking them under my boat cover.
Live and learn.

[rofish]

Mark,
Your problem may have nothing to do with chemistry, but with physics.
If you sealed the wood at low temperature, heat would expand anything which is left in the wood (air, acetone, water, etc) and so such problems will certainly appear if the difference in temperature is very high. To diminish the possibility of physics cracking your lures, you simply have to seal your lures at a higher temperature (preheat them before sealing). And you will do nothing wrong if you preheat them before any other layer you add to them. That's because the clearcoat will always crack from inside out, not from the pressure from the outside the lure. The lure can stand a high pressure from the outside.
If, in the case you described, you saw that the primer was not cracked, that doesn't mean a thing. The situation may be that air escaped from the lure, but did nor crack the primer, it just went through it, causing the problems to other layers.

[mark poulson]

rofish,
I wonder if it was the Minwax Wood Hardner that I used as a sealer this time. Maybe it off gasses for a longer time than their Polyacrylic Sealer that I had been using.
Or maybe I put the primer on too thick, and it still had some solvents buried in it.
Whichever it is, I sanded the damaged section down to the primer, reprimed it with two light coats, hit it with the hair dryer, and am letting it hang in my garage which is up to 75+ degrees al;ready, and it's only 10:45 in the morning.
I will hair dry it again before I start my painting, and really well between coats, and let it sit for a day before I put on the glitter and topcoat.
Mostly, I'll keep the lures out from under the black boat cover in the summer, where temps get up over 100 degrees every day.
Fingers crossed.

[Downriver Tackle]

There's an easy way to tell if a layer wasn't fully cured. Too late because you already repainted. Next time, take a piece of very sticky tape, nylon tape prefered. If not, duct tape. Lay it across the crack, press down real well, then rip it off perpendicular to the crack. You''ll have some paint on the tape. Look to see which layer failed. If that layer is on both the chip and the lure still, it was too soft or under cured. If it was a clean delamination of a layer, it was and adhesion issue of some sorts.

If that wood hardener, or any of the paints, had mineral spirits in it, that stuff is a pain to get out of the film! Even after heat-curing, I'd wait 24 hours before putting anything else over it, especially something waterbased.

[mark poulson]

That's a slick idea! I found that the white primer had stuck both to the epoxy/paint section, and to the lure, so it had to be the weak link. I think I just put it on too thick, and didn't give it a chance to really cure. Operator error.
Man, I hate when there's no one to blame but me!
I will be keeping the lures out of the heat. Direct sunlight heat seems to be okay, but baking under the boat cover just cooks the lures.

[Downriver Tackle]

Maybe use that "under the cover" set-up as your drying cabinet.

[rofish]

Yes, Downriver T. is right. That space under the black cover could be an excellent dryer for your lures
I was thinking to suggest that you paint that black cover in white, so if you forget your lures there, you will not have such problems anymore. And you could make a drying box at home, painted in black
But what I wanted to say earlier is that physics will take it's toll on every chemical you may find on the market, regardless of quality. So you do not have to think that a stuff like Minwax may be the culprit.
What you have to think of in the first place is how to reduce the difference between the 2 temperatures: the one at which you have sealed your lures, and the one under the cover of your boat.
Everything you say about thin layers of paint which have to dry perfectly before applying another coat is right, but this hobby requires a physics orientated mind as well.