Unable to paint boat

[iamandrew]

Hi everyone
Ive got a persuit that ive sanded down and was going to paint,
applied some prepsol onto it to get all the crap off the hull, then painted it
only to find out that after a bit, the entire front of the boat starts getting big cracks and spider lines all through it
I have no idea what ive done wrong
I done the hatch in the exact same way and it turned out perfect.

I sanded it down again, and then painted it (the hull) should i sand the whole thing down to remove the gel coat then try again?

[greg pereira]

no drew sand it then put a couple of lite coats of primer and then sand it and u will fix your problems

[siberianhusky]

Where you using Krylon paint? If so thats the problem. Try dupli-color auto touch up paint and use the same type (lacquer or enamel) for the entire paint job.
I really like the lacquer, dries very quick and lacquer is an easy paint to touch up as repairs will "melt" into the original paint.
I've used automotive base/clear paint and that stuff is amazing, but expensive unless you know somebody who is an autobody guy, they usually have some colour left over after painting a vehicle. If you know somebody like that they may be willing to spray your boat at the same time they are doing a vehicle of the same colour.
Thats how I'm probably going to get a few painted this winter, one of our reserve plow drivers is a body man by day, just going to wait until he is doing something cool and get him to shoot the boat the same colour.
LOL anything to avoid painting. It's no wonder my scratch builds all end up natural wood with clear coat.

[iamandrew]

I just used some cans of Car spray touch up paint :S
Ive never had this problem this bad.
is it possible that its some different type of gelcoat?
maybe the prepsol just weakened the gel coat? I got no idea the hatch turned out perfect

[dana]

I just used some cans of Car spray touch up paint :S
Ive never had this problem this bad.
is it possible that its some different type of gelcoat?
maybe the prepsol just weakened the gel coat? I got no idea the hatch turned out perfect

is it lacquer?

[rc2266]

What was the temp and humidity?

[iamandrew]

well about 24 degrees
paint says its acrylic laquer

it was sunny as well but i painted it inside

im about to sand the damm thing down ... again, they try a real light coat of undercoat

[rc2266]

I just noticed before that i painted one and everything was great, the next day temp dropped almost 15 degrees and it caused exactly what you described.

[iamandrew]

yeah, well
the thing is right, it done it the first time i painted it
so i sanded it off and tryed agian
but then found that the cracks came up in the exact same spots

[dana]

Lacquer tends to crack. I would try enamel

[detox]

Did you use matching primer before painting. Primer helps paint bond better and also seals. Allways use matching primer and paint. Krylon primer and paint has allways worked good for me (no peeling when hatch tape removed), but colors choices are few.

[iamandrew]

yeah.... and whats worse.... all the same brand as well so i still dont know !

[siberianhusky]

You say the cracks came up in the same spots again, are they the same cracks?
Could be the gelcoat has some spidering and when you sanded it down it opened them up a bit, then when the paint shrinks it splits over the cracks. Any imperfections under the paint will really show up once painted.
If this seems to be the problem you could work some bondo into the area, sand it all off just to leave the hairline cracks filled, prime and paint.
SOmething else I just thought of, was the boat ever polished with something containing silicone? Is there a chance there is some kind of contamination?

[iamandrew]

I have not polished the boat before, the hull was new when i got it but its likely it has probably been polished from when it was made.
I had sanded the hull down with 320, then 800,.... then 1500 sand paper
it took me all week.... what a waste maybe the 1500 is too fine for undercoat? i thought it would be better to get a good smooth hull first

[liteumup69]

Sounds like your applying your coats to heavy, The "cracks" or wrinkles are usually a sign of two much paint to soon, You need to sand down back to the glass, use a surface prep, then apply lite coats of a good primer, something like a PPG High build primer, you can get it in spray cans at a good automotive shop, then sand down your primer (2-3 coats) with 300grit wet, use the surface prep again, and then light coats of paint, first coat should be a fine mist, second a little heavier and so on, allow at least 10min between coats, depending on the out side temp/humidity, If you need more help ask, I do classic car restoration and custom paint.... Paul
P.S DON"T use bondo, it will crack, use UPOL Fiberall,