lowkee
Lieutenant Commander
- Joined
- Dec 13, 2008
- Messages
- 1,890
Re: '1990 Bayliner Capri 2050 BR - Deck, stringers, transom, custom interior'
Okay, okay, you guys all pressured me into a (mostly nowhere) update! Seriously, though, thanks for the kudos and encouragement.
I took a bit of time off after getting back from vacation simply because my arms were still tired from sanding and 'the fear' was back in me from painting hassles.
Since then, I have dismantled a couple of computer cases I have at home in order to gain some painting practice on items smaller than a 20 foot hull. I also am using a couple of glass shelves for practice, as I can use a razor to scrape the paint off after a session, which comes in really handy for total mess-ups.
To keep everyone up to date with my thinking, I am back to wanting to spray the paint onto the hull using my HVLP gun. I have run into more than my fair share of snags, including paint which never seems to harden (Pettit One-part topside paint.. sucks), and clear coat which causes the Pettit to curdle when applied (UPDATE: It was the acetone used to thin the clear coat which caused the curdling, not the clear coat itself).
So, here is what I am doing to fix these annoying and super-huge time consuming issues. I am scrapping the Pettit topside paint and going with automotive base-coat/clear-coat hull painting. I have two-part base coat on order and plan to use the Pettit remainder (~3 quarts) to paint the inside of the hull and the deck. Then if it goes bad, who really cares, I can just slop a new coat on and orange peel won't be an issue, since it'll have grit mixed in anyhow (for the deck, at least).
In the mean time, I have been spraying the computer cases and the glass shelving with the Pettit in various ways, more air, less air, more paint, thinner paint, wider stream, with acetone, with mineral spirits, then letting it dry, checking for orange peel, uneven spots, too thin, too thick, gritty, or any kind of bad spray (which has been pretty much all of my attempts so far) and trying to adjust my technique to fix the problem.
I plan to do this until I have fully learned how to use an HVLP gun and apply paint without causing myself tons of unneeded sanding time. Will this take a month? Maybe, but at least I'll not be wasting any more paint sand paper and, most importantly, effort! I will have a pearl paint job if I have to become a paint technician at an auto store in order to do it! I am set in my ways and will not stop until I get it right. After all, my truck, lawn tractor and motorcycle could use a paint job, too. I certainly don't want to repeat this nightmare which each of those.
Does that count as a decent update
I'll post some of my paint practice photos tonight or tomorrow, including some pearl examples, although capturing the pearl effects on camera seems a challenge.
So far, for those who also wish to learn to use HVLP guns and to spray paint in general, here are some things I have learned so far (I will update this as I learn more/different):
- Mineral spirits (thinner) tends to evaporate very slowly, leading to runs and sags
- Acetone (thinner) evaporates very quickly, causing orange peel (one of many causes of orange peel) as the paint does not have enough time to self level before the acetone flashes off
- Acetone will cause just about any enamel to curdle within the 1st 30 days of curing
- Two-part clear coat goes on very thin, so 2-3 coats should be expected prior to doing any sanding.
- Automotive paint ($41/gal) is way cheaper than marine paint ($100/gal).
- Two part paint (with hardener/activator) is more time critical (two hours to cure), but in no way, shape or form should you use one part paint, unless you have at least a month or more to wait for it to cure, and up to 4 months for a full cure.
- Two part paint curing time can be altered by varying the reducer type. They make fast, medium and slow reducer, which varies the spray-able time to roughly 15min, 45min, 2hrs respectively. Temp and humidity also impact these times, so plan accordingly.
- HVLP guns aren't as easy to use properly as they look.
- Spraying paint means the paint needs to be almost as thin as water. If it looks soupy it is likely too thick for your spray gun (with a standard 1.4mm tip)
- Orange peel can be caused by: paint too thick, gun too close, too much air, not enough air and too much paint. Any of those factors can be a contributing or only cause.
- ALWAYS do a complete paint job on a test panel prior to beginning the real job. Stripping a test panel 2-3 times is easy; Stripping and re-sanding your project 2-3 times.. not so easy.
- Enamel is meant to be baked, which is why it doesn't self-level very well and takes so long to cure.
- The most important thing I learned about paint and painting.. Enamel cannot be sanded, so don't jump in thinking you can just sand down the orange peel or paint sags, you can't with enamel paint. Use urethane if you plan to sand the final coat.
Okay, okay, you guys all pressured me into a (mostly nowhere) update! Seriously, though, thanks for the kudos and encouragement.
I took a bit of time off after getting back from vacation simply because my arms were still tired from sanding and 'the fear' was back in me from painting hassles.
Since then, I have dismantled a couple of computer cases I have at home in order to gain some painting practice on items smaller than a 20 foot hull. I also am using a couple of glass shelves for practice, as I can use a razor to scrape the paint off after a session, which comes in really handy for total mess-ups.
To keep everyone up to date with my thinking, I am back to wanting to spray the paint onto the hull using my HVLP gun. I have run into more than my fair share of snags, including paint which never seems to harden (Pettit One-part topside paint.. sucks), and clear coat which causes the Pettit to curdle when applied (UPDATE: It was the acetone used to thin the clear coat which caused the curdling, not the clear coat itself).
So, here is what I am doing to fix these annoying and super-huge time consuming issues. I am scrapping the Pettit topside paint and going with automotive base-coat/clear-coat hull painting. I have two-part base coat on order and plan to use the Pettit remainder (~3 quarts) to paint the inside of the hull and the deck. Then if it goes bad, who really cares, I can just slop a new coat on and orange peel won't be an issue, since it'll have grit mixed in anyhow (for the deck, at least).
In the mean time, I have been spraying the computer cases and the glass shelving with the Pettit in various ways, more air, less air, more paint, thinner paint, wider stream, with acetone, with mineral spirits, then letting it dry, checking for orange peel, uneven spots, too thin, too thick, gritty, or any kind of bad spray (which has been pretty much all of my attempts so far) and trying to adjust my technique to fix the problem.
I plan to do this until I have fully learned how to use an HVLP gun and apply paint without causing myself tons of unneeded sanding time. Will this take a month? Maybe, but at least I'll not be wasting any more paint sand paper and, most importantly, effort! I will have a pearl paint job if I have to become a paint technician at an auto store in order to do it! I am set in my ways and will not stop until I get it right. After all, my truck, lawn tractor and motorcycle could use a paint job, too. I certainly don't want to repeat this nightmare which each of those.
Does that count as a decent update
I'll post some of my paint practice photos tonight or tomorrow, including some pearl examples, although capturing the pearl effects on camera seems a challenge.
So far, for those who also wish to learn to use HVLP guns and to spray paint in general, here are some things I have learned so far (I will update this as I learn more/different):
- Mineral spirits (thinner) tends to evaporate very slowly, leading to runs and sags
- Acetone (thinner) evaporates very quickly, causing orange peel (one of many causes of orange peel) as the paint does not have enough time to self level before the acetone flashes off
- Acetone will cause just about any enamel to curdle within the 1st 30 days of curing
- Two-part clear coat goes on very thin, so 2-3 coats should be expected prior to doing any sanding.
- Automotive paint ($41/gal) is way cheaper than marine paint ($100/gal).
- Two part paint (with hardener/activator) is more time critical (two hours to cure), but in no way, shape or form should you use one part paint, unless you have at least a month or more to wait for it to cure, and up to 4 months for a full cure.
- Two part paint curing time can be altered by varying the reducer type. They make fast, medium and slow reducer, which varies the spray-able time to roughly 15min, 45min, 2hrs respectively. Temp and humidity also impact these times, so plan accordingly.
- HVLP guns aren't as easy to use properly as they look.
- Spraying paint means the paint needs to be almost as thin as water. If it looks soupy it is likely too thick for your spray gun (with a standard 1.4mm tip)
- Orange peel can be caused by: paint too thick, gun too close, too much air, not enough air and too much paint. Any of those factors can be a contributing or only cause.
- ALWAYS do a complete paint job on a test panel prior to beginning the real job. Stripping a test panel 2-3 times is easy; Stripping and re-sanding your project 2-3 times.. not so easy.
- Enamel is meant to be baked, which is why it doesn't self-level very well and takes so long to cure.
- The most important thing I learned about paint and painting.. Enamel cannot be sanded, so don't jump in thinking you can just sand down the orange peel or paint sags, you can't with enamel paint. Use urethane if you plan to sand the final coat.
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