Lowest Temperature for Bottom Paint Application

[thomm225]

Originally Posted by Shrew

Which boatyards are you seeing the behavior in? Technically it can't be BOTH. They can't be both conscientious and applying paint well outside of the manufacturers' recommendations. (e.g. damp hulls and/or outside recommended temperature ranges).

I'm thinking they know what they can get away with due to their experience doing this most every day. Lots of their customers are returning customers also.

I will try and stay within specs, but if pressed, I may do the last touch up areas from the stands and the keel blocks slightly out of specs. I did this last time a few hours before launch and saw no differences in these ares as compared to the rest when the boat was pulled on November 1.

I did mine in 2011 at 90 degrees plus, in 2015 at 48-55 degrees, and this time it could be on the cool to cold side also.

I may get stuck in the yard into March though with the higher prices to complete the topside and decks waiting for the temps to raise so I may delay the bottom job also

[sand6000]

Antifouling (Bottom paint) is more forgiving than other coatings BUT the information given on the manufacturers data sheets (check their web sites) is the the best guide. For example International Micron 66 states minimum air temp is 41 Degs, however the critical thing is the substrate temp which must be 5 Degs above the Dew Point. If you don't have a guage to check Dew Point then ring your local Met Office. Also for best results the paint should be above the air temp.

Cheers,
Pat
(27 years with International Tech Sales)

[thomm225]

Originally Posted by sand6000

Antifouling (Bottom paint) is more forgiving than other coatings BUT the information given on the manufacturers data sheets (check their web sites) is the the best guide. For example International Micron 66 states minimum air temp is 41 Degs, however the critical thing is the substrate temp which must be 5 Degs above the Dew Point. If you don't have a guage to check Dew Point then ring your local Met Office. Also for best results the paint should be above the air temp.

Cheers,
Pat
(27 years with International Tech Sales)

Thanks for the info.

I think we have 80 or so weather stations in the area that provide the dew point, humidity etc

[30yearslater]

I use Pettit Vivid White. Last year was so friggin cold in April I said the hell with it and painted with the temps in the mid 30s to mid 40s. That or I wouldn't launch till June waiting for anything stable above the recommended 50 for 24 hours. I have to admit I thought I just wasted a whole lot of money but I didn't care at that point. It turned out the first coat applied well without the characteristic bleed I was experiencing where some areas showed yellowish tints when above 50. After a week I applied the second coat only to have the bleed not occur again. Same miserable cold. At haulout this year the stuff still looks good enough that only where the slings scuffed it and the pressure washer blasted through need a touch up. For me at least I won't be painting again above 50 since the results were so good.

[thomm225]

Originally Posted by 30yearslater

I use Pettit Vivid White. Last year was so friggin cold in April I said the hell with it and painted with the temps in the mid 30s to mid 40s. That or I wouldn't launch till June waiting for anything stable above the recommended 50 for 24 hours. I have to admit I thought I just wasted a whole lot of money but I didn't care at that point. It turned out the first coat applied well without the characteristic bleed I was experiencing where some areas showed yellowish tints when above 50. After a week I applied the second coat only to have the bleed not occur again. Same miserable cold. At haulout this year the stuff still looks good enough that only where the slings scuffed it and the pressure washer blasted through need a touch up. For me at least I won't be painting again above 50 since the results were so good.

Which brings me back to my point that the guys at the yard know what they are doing because they do it almost every day or at least much more than your average sailboat owner

[30yearslater]

Originally Posted by thomm225

Which brings me back to my point that the guys at the yard know what they are doing because they do it almost every day or at least much more than your average sailboat owner

Many decades ago I worked in a marina in Rochester, NY and we regularly painted bottoms all winter. Of course this was when VOCs weren't a thing and Red Lead was real lead. The newer water based formulas that are environmentally friendly may be a different beast. Vivid has fumes aplenty, solvent based, so they may be using solvent based paints.

[gulfcoastsailor]

I have a file for such questions. Sadly it getting too full, too fast.

[thomm225]

Originally Posted by gulfcoastsailor

I have a file for such questions. Sadly it getting too full, too fast.

No need to be sad about it.....

If I had more time, I might paint today. It's almost 45 degrees, Sunny, with 45 % humidity. I'll see if they are painting later at the boatyard

[thomm225]

So I did find a note on the Micron Label that said if the temperature falls below 50 degrees F during the drying time extend the drying time which tells me as long as the paint will spread properly it should be OK to paint near 50 degrees

This could be important since the price of boat storage in this boatyard goes from $216/month thru February to over $600/month in March

[CaptTom]

I get a kick out of the paint cans which demand that temperatures be in the 70's F, night and day, with low humidity, for days on end.

Of course, that's never happened in Maine, at least not until July or August. Everyone paints their boat in the spring, and does the best they can. Many of us have found ourselves painting the water line first, so we can finish up the bottom from underneath after it starts raining. You do what you gotta do, otherwise you'll never get in the water!

[thomm225]

Originally Posted by CaptTom

I get a kick out of the paint cans which demand that temperatures be in the 70's F, night and day, with low humidity, for days on end.

Of course, that's never happened in Maine, at least not until July or August. Everyone paints their boat in the spring, and does the best they can. Many of us have found ourselves painting the water line first, so we can finish up the bottom from underneath after it starts raining. You do what you gotta do, otherwise you'll never get in the water!

Completely understand but evidently the guy that posted earlier from Florida doesn't!

[thomm225]

So we got above 50 degrees for a few hours today and I was able to apply the first coat of bottom paint. I thought it looked pretty good on my 44 year old boat

I like painting at these low temps since the paint doesn't try to dry out in the pan while you are working like it does when the temps are in the 80's and above

A boat was launched today and just before launch they painted the areas of the keel where the blocks were. The boat was in the water 30 minutes later