Understanding Clear Coat

jpmurphy

Petty Officer 1st Class
Joined
Jan 14, 2009
Messages
358
Re: Alum Gregor

Finished painting the bottom of my boat a couple of days ago. I sealed the paint with Rust-Oleum "Crystal Clear Enamael". Standing a few feet away , the finish is not even. There are glossy spots and flat spots. Like the difference between glossy paint and flat paint. I used the Rust-Oleum "Clear Metal Primer" ( couple of coats) and Rust-Oleum "Gloss Protective Enamel". (couple of coats) Both are white. I'm sure I got adequate coverage with the crystal clear enamel because in one spot I overdid it and the painted area actually "wrinkled". I did use steel wool between the coats of the paint.

Except for the very forward portion of the bow, none of this area will show except when trailered. However, there are other above-water line areas that I plan to paint. This "two tone" finish is not what I was hoping for.

Am I using the incorrect product for the finish/sealer ?
I see forum references to automotive finish/sealers but thought that referred to fiberglass gel coat or whatever. I'm a little fuzzy on sealing metal finishes as my experience has only been with woodworking and thats a whole different ball game.

Can't do anything about the paint for a couple of days yet due to the weather/temps but inquiring minds gotta know. :rolleyes:

Thanx in advance.
 

a70eliminator

Captain
Joined
Sep 9, 2007
Messages
3,762
Re: Understanding Clear Coat

Reguarding wrinkles, I don't think you overdid it for that will cause runs not wrinkles, wrinkles happen when you either wait too long between coats or not long enough. It's like the paint has to be still wet between coats, or it has to be completely dry like 24 to 48 hrs depending on humidity, anything in between usually will wrinkle.
 

fishrdan

Admiral
Joined
Jan 25, 2008
Messages
6,989
Re: Understanding Clear Coat

Explain the dull area's, are these streaks or large area's, what areas were affected, how did you paint the hull top>bottom or left>right in sections. Also, did you use rattle cans or a spray gun and bulk paint.

I'm thinking you had dry areas with not enough paint applied and/or not enough overlap between the spray passes. I've used Rustoleum several times and it's pretty forgiving since it flows out nice and dries slow,,, though I have never used their clear coat.

If you use a cup gun the finished product will turn out much better since you can apply the paint quicker and with fewer passes. A rattle can throws out a 2-3" round pattern while a cup gun can throw out a 6" fan pattern, much easier to use for large areas. I use a $15 gravity feed cup gun from Harbor Freight and it works great for shooting Rustoleum, thinned with just a bit paint thinner,,, maybe 10%. I used a touch of Floetrol on the last thing I sprayed with Rustoleum and the surface came out very glossy and flat, no orange peel or dull areas.
 

jpmurphy

Petty Officer 1st Class
Joined
Jan 14, 2009
Messages
358
Re: Understanding Clear Coat

Explain the dull area's, are these streaks or large area's, what areas were affected, how did you paint the hull top>bottom or left>right in sections. Also, did you use rattle cans or a spray gun and bulk paint.

I'm thinking you had dry areas with not enough paint applied and/or not enough overlap between the spray passes. I've used Rustoleum several times and it's pretty forgiving since it flows out nice and dries slow,,, though I have never used their clear coat.

If you use a cup gun the finished product will turn out much better since you can apply the paint quicker and with fewer passes. A rattle can throws out a 2-3" round pattern while a cup gun can throw out a 6" fan pattern, much easier to use for large areas. I use a $15 gravity feed cup gun from Harbor Freight and it works great for shooting Rustoleum, thinned with just a bit paint thinner,,, maybe 10%. I used a touch of Floetrol on the last thing I sprayed with Rustoleum and the surface came out very glossy and flat, no orange peel or dull areas.

The dull spots are about 8"x8" or thereabouts. Different areas: different sizes but none real large. I sprayed the crystal clear on the entire underside of the hull/bottom of the boat spraying with a rattle can left to right and overlapping each section. One can port, another starboard. I only stopped to open a new can. Took about 15-20 minutes for entire boat.

There is a possibility either I applied too sparingly, or the room temp was not warm enough. I would think with regards to room temp, if one section dries out smooth and glossy, so should everything. eh ? I probably didn't overlap enough with each pass of the can. If that were the case, that would explain the "dull" spots. Be a couple of days before warmer temps before I can redo the dull spots, but I wanted some insight incase I was using incorrect products.

As for the wrinkles; they've been sanded down. Still remain a mystery. I'm sure it was nothing more than operator error.

Thankyou very much for your input. :)
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
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May 19, 2001
Messages
26,071
Re: Understanding Clear Coat

For straight clear coat I usually use automotive grade PPG or MTK clear that comes RTS (ready to spray). Based on the aluminum I would have added a touch of fish eye additive and sprayed a few coats.
 

jpmurphy

Petty Officer 1st Class
Joined
Jan 14, 2009
Messages
358
Re: Understanding Clear Coat

For straight clear coat I usually use automotive grade PPG or MTK clear that comes RTS (ready to spray). Based on the aluminum I would have added a touch of fish eye additive and sprayed a few coats.

Fish Eye additive ??
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,071
Re: Understanding Clear Coat

It cuts back on the fisheyes in the finish actually it is called a fisheye reducer ....... if the surface was having a fisheye problem this will ut back on about 85% of them.
 

wca_tim

Lieutenant Commander
Joined
May 28, 2007
Messages
1,708
Re: Understanding Clear Coat

err... I think even the cheap rattle can clear is aggressive enough to pull rustoleum enamel. Generally wrinkles are when the solvents in the top coat (in this case clear) are dissolving the underneath coat... OR when the coat underneath is not fully dry and dries at a slower rate than the top coat, then it makes sort of fissures... Hope this is helpful.
 

jpmurphy

Petty Officer 1st Class
Joined
Jan 14, 2009
Messages
358
Re: Understanding Clear Coat

err... I think even the cheap rattle can clear is aggressive enough to pull rustoleum enamel. Generally wrinkles are when the solvents in the top coat (in this case clear) are dissolving the underneath coat... OR when the coat underneath is not fully dry and dries at a slower rate than the top coat, then it makes sort of fissures... Hope this is helpful.

At this point in my learning curve; everything is helpful... :redface:

We have a 5 day window of warmer weather forcasted beginning today so this should give us a long enough stretch of time to go from primer to clear coat on the spots I have to repair. The last coat of clear is nearly a week old so going back over that shoould present no problem.

I'll post after a few more days with a recap for other users.

Many Thanx..
 
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