First time polyurethaning... help needed?

[SeFu]

i applied my first coat of oil based polyurethane today at noon (almost 7 hours ago).

the table is in my house... about 74 degrees and very low humidity.

I am just wondering how long i need to wait until i can lightly sand and put on my next coat?

Ive heard 24 hours... is that right?
ive also heard that you can apply it within 12 hours and if you do, you dont need to sand.... is that right?

thanks for your help!
-SeFu

[Wongo]

SeFu (does it mean master?)

Yes 24 hours is about right. You can touch it after 8 hours to see if it is fully dry.

In Sydney, it takes only 6, 7 hours to dry in hot summer but up to 30 hours in winter.

Regards

[SeFu]

hello, yes... its a nickname my friends gave me a long time ago. Never got rid of it.

I live in the United States... in Florida. Its very hot down here, but also very humid. So I chose to do it in my house since I decided the lower humidity would be more beneficial to its drying time than the outdoor heat would. I may be wrong though.

How will I know when the urethane is hard enough to begin a light sanding and apply the next coat?

as I run my fingers over it now... it feels relatively hard, but tacky in the sense that my fingers dont "glide" over the surface. I suppose ill just wait the full 24 hours before applying the next coat.

[HonkyLips]

In these sorts of situations, just think about the difference between how long you could wait and how long you're going to use the table.

The table might last you 10 years. Maybe 20. Even if you get sick of it quickly, you might use it for 1. If you don't wait until the first coat is properly dry, perhaps the final result won't be as good. You could spend the next 1 / 10 / 20 years looking at a result which is a bit odd because you didn't wait an extra 1 day..... So it's not too much to wait just a bit longer....

Anyway, that's how I think of it sometimes.

[journeyman Mick]

SeFu,
polyurethane is dependant on moisture for curing. Higher humidity = faster cure. Might pay to work outside in the shade, in your garage perhaps.

Mick