What minimum temperature should I look for to paint the boat, antifoul and topsides?

Even Chance

Even Chance

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Its getting close to that time of year again, but with the recent poor weather I thought I'd ask a question Im sure a few folks are wondering:-
When will it be a good day to paint my boat?
What are the minimum temperatures the paints will need to dry?

We're getting some good dry sunny days up here (today included!), but the temps are only +1 or 2 degC, and time is running out fast before crane-in.
We generally dont get snow in Caithness much. Way too close to the sea on most sides!

I bought some International "Nautical" general purpose antifouling, and some good old exterior gloss "Johnstone's", for the topsides. Its been 6 years since her last paint, and it could have gone longer had I not made a few changes over the winter that require paint as well. May as well do the whole lot.

Whats the forums take on this?

Thanks
 
I'm waiting to apply FLAG Multi-Purpose Metallic Primer before antifouling but all it says is the primer has a flash point of 42 degrees. Not much chance of that.
 
No info on the tins regarding temperatures.

Theres some sunshine in the post Searush. Royal Mail will probably lose it though as usual!;)

Was due to be the 30th here for crane-in. Not looking very likely. Ive told the gaffer that I may need a few days off at short notice. Just need the weather to co-operate!
 
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Yep having the same thoughts, boat back in on the 26th. I wish it was just a temp issue, I have been waiting for a dry day to paint. Anyway I was looking at my Jotun tin, Sikaflex and Hempel epoxy last weekend and they all seem to state min 5c. BUT if you keep your paint at room temp you can probably get away with it being below 5c, but perhaps not below 0c. Drying time of course will be longer.
 
Scubadoo said:
Yep having the same thoughts, boat back in on the 26th. I wish it was just a temp issue, I have been waiting for a dry day to paint. Anyway I was looking at my Jotun tin, Sikaflex and Hempel epoxy last weekend and they all seem to state min 5c. BUT if you keep your paint at room temp you can probably get away with it being below 5c, but perhaps not below 0c. Drying time of course will be longer.
Click to expand...

Your in a worse situation than I am by far! At least its relatively dry here. A bloomin snow shower just swept in tho. Nothing lying as per usual and its gone as quick as that...
 
Frankly, to be sure nothing goes wrong - temperature should be 10 C or more and that means temperature of boat, not just air. After it's painted, when curing, temperature still above 5 C.
Yes, I know... but didn't made any painting on my boat last "summer" at all, as might be waste of money (and time); Beside antifoul all the rest will wait until sailed into Med...
 
As suggested read the product data sheet and follow the advice,

2 pack products may well not cure above a certain minimum temperature.

The enemy of single pack products at low temperatures is condensation on the surface and on the product before it is dry.
You will usually find a recommendation that the substrate temperature should be a couple of degrees above the dewpoint.

Even if the product has been stored in a warm place or warmed before use it will not prevent condensation on the surface if its not a little above the dewpoint, or on the product after application.

Remember your moist breath will increase the dewpoint locally and increase the risk of condensation on a cold surface.
 
Rossynant said:
Frankly, to be sure nothing goes wrong - temperature should be 10 C or more and that means temperature of boat, not just air. After it's painted, when curing, temperature still above 5 C.
Yes, I know... but didn't made any painting on my boat last "summer" at all, as might be waste of money (and time); Beside antifoul all the rest will wait until sailed into Med...
Click to expand...

+1
 
If I waited for it to reach 10DegC, I'd have to use the 3 good days of summer around here instead of sailing! I cant wait until June, sorry! lol
 
The tins will say the minimum. I have just finished painting and here's my thoughts...

Hempel Underwater primer 5degrees C - I tested the hull and keel temperature to check but a good dry air helps alot at colder temperatures. Overcoat time is 6 hours minimum.
International Toplac, 5 degrees C - I thinned this about 10% and needed a few coats but touch dried quickly, overcoat time is 24hrs minimum.
 
I think I might just rub mine down with wet & dry now & hope for a chance to paint one side at a time on a beach in the summer. I've got a couple of holes in the foredeck to fill as well, so I will concentrate on them as they can be locally sheltered & warmed.
 
If push really comes to shove the best trick is to sit your can of paint in a pot of HOT water but not boiling wipe the hull down with a paper towel to remove microscopic moisture particles then tak rag it and start painting, make sure you continually stir the paint to keep it at an even temperature whilst painting Antifouling is slightly more tolerant and should not need "drying" or heating before application maybe be add a few percent of thinners to ease application and measure the addition accurately. I used to ask boat owners to add a few percent freehand and without exception they added no less than ten percent and some an awful lot more!
 
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