How long between coats of gloss?

abankerbutnotafatcat

I was just wondering, you have to sand to get a key on gloss paint before painting over. Yet you should put on two coats of gloss i.e. one coat over another. So what is the maximum amount of time you can leave between coats before you would need to get a key for it to adhere?

DVardysShadow

At least a month, I would say.

Yorkie1

A month? Really?

The_Pedant

What does the tin say?

The ones I have here say 16 hours to dry & to leave at least 16 hours between coats.
May depend on the type of gloss you're using & what the solvent is.

nickj_2

i would say a few days for it to harden off , when you do sand it , use a very fine sandpaper otherwise it will tear , if it looks ok- a 2nd coat isn't normally required

phill99

You don't put on 2 coats of top coat. You put on 2 coats of undercoat and 1 of gloss.

Cinquestelle

abankerbutnotafatcat wrote: »

I was just wondering, you have to sand to get a key on gloss paint before painting over. Yet you should put on two coats of gloss i.e. one coat over another. So what is the maximum amount of time you can leave between coats before you would need to get a key for it to adhere?

The answer is 24 hours.

Yours is a very good question and one that actually occurred to me a couple of years ago when I had a project that involved gloss finishing. The idea of rubbing down a lovely new coat of paint to provide a key for the second coat didn’t seem right. I had never seen that advice in any of dozens of diy books. Moreover, when I looked at the instructions on the tin of paint I was using there was no suggestion let alone instruction to rub down the newly painted surface before applying the recommended second coat.

I telephoned Dulux and they confirmed my instinct was correct - within time limits. The second coat of gloss should be applied as soon as the first coat has dried but before it has fully hardened, ideally this should be within 24 hours. Effectively, this means re-coating 16-24 hours later. I imagine there is a certain tackiness that remains enabling good adhesion. Leave it beyond 24 hours they said, and one will need to rub down the first coat. I followed the advice given and I had no problems, the second coat went on as easily as the first.

Be sure to apply the first coat at a time when you absolutely know you will be able to finish the job the next day.

MRSTITTLEMOUSE

I usually leave anything between 24 to 72 hours depending on the surrounding temperature in the room.
In the summer or if its warm you can overpaint in 24 hours but in cooler temperatures I tend to wait a bit as the paint seems to take longer to harden.
Been using this method for 40 years and its never let me down yet.

DVardysShadow

I would put gloss on gloss, but I would not sand down the intermediate coat until it was well hard. Even beyond 3 days, you can expect not quite dry paint to adhere to the sandpaper and for a long time after, it will be all too easy to sand and you will be back to the undercoat before you know it, which defeats the point of putting on another coat.

ormus

i would leave at least 24 hrs between coats. no need to wait for a month!