Paint recommendations ?

[powrguy]

I previously posted about my tale of woe trying to paint my boat with one-part polyurethane. (Blue Water Marine Mega-Gloss Polyurethane).

I had first tried the roller, then the brush. In the roller case, I had roller marks and lap marks. In the brush case, I had brush marks, and lap marks. (The roller coat was thinned about 10% with Hi-Flash Naptha, as recommended, and I had curtains and some sags). The brush application was UNTHINNED, and there were Trophy Sags and curtains with that application. It's shiny alright, but it looks like woodgrain instead of fiberglass.

I've begun sanding it smooth, again, with 220 grit. Now, my thought is to either try spraying it (maybe using mineral spirits and a paint viscosity cup) and hopefully with an HVLP gun.

My question is whether HVLP is the way to go, or just shoot it with acrylic enamel with hardener, like I used to paint cars with, in a conventional gun. The overspray is my concern, as I will have to build a plastic-covered structure temporarily to house the spraying. The boat is a 20' center console.

Any ideas? Should I try to spray the polyurethane, or just get some other paint and some good primer?


thanks

 

[powrguy]

Re: Paint recommendations ?

Well, since no one else on the Forum evidentally has ever had these issues, I'll answer myself based on searching every paint-related issues I could find on the Internet.

The paint was put on too thick, and waiting only 4 hours for the "dry to the touch" time was insuffiecient for re-coating. The initial coat was too thick, and the second coat sealed the surface such that complete proper drying couldn't occur, IMHO.

Therefore, I sanded it all down, scraped areas that obviously were way too thick and soft, and have washed in down again in prep for painting. This time, a VERY LIGHT COAT of thinned paint, as suggested in another response that is the consistency of milk, is going to be applied. Then, 24 hours before the next coat, sanded if necessary between coats. If it takes 3 coats, so be it.

 

[mrdjflores]

Re: Paint recommendations ?

i don't know about the brand your using...but i've been using the one-part Interlux Bightsides and the one-part Pettit Easypoxy...

always sand between coats with 320 wet/dry paper.....

In my thread, i just put on the 3rd coat on the sides and the first coat on the bottom... there are 2 (maybe 3) coats of primer under the paint...mainly because the boat used to be blue...

on applying the paint...i used the white foam rollers from Home Depot that are 5" white..and labeled for ultra smooth...and tip off with their "better" labeled 4" brush (around $11 a piece)

I didn't thin any of my paint...put on very thin coats...and only roll on about a 2-3' area and then come back and tip off...the little 'woodgrain' effect you are seeing is that the paint has started to flash already or your are applying too much pressure with the paint brush

hope this helps...

 

[powrguy]

Re: Paint recommendations ?

I'm using Blue Water Marine Mega-Gloss, which is a one-part polyurethane, also branded as West Marine Seagloss (same paint). It's similar to the Interlux Brightside.

I found that using a thinned paint, consistency of milk, and tipping with a foam brush finally did the trick. The paint was just too thick to flow out properly un-thinned, I found, after 4 attempts. I got high quality Mohair rollers, 1/4" nap, pro quality. I cut them in half, and used a 4" roller instead of the 9" rollers. Worked fine. I have to apply the second coat tomorrow, and I'll sand with 320 grit, just to scuff the surface. I don't have many skips or any runs; just a couple of insects on it in a half dozen places. Otherwise, it flowed out beautifully this time. I applied about 1 1/2 quarts of paint to the hull on a 20 footer with an 8 foot beam. There were two coats of primer still on it, with sanding with 220 grit between those coats. I am allowing a full 24 hours before I sand.

Did you sand wet, or dry?


thanks