Just to add my two pennies worth to this thread.
I decided to tidy up the transom on my Ocean, so scraped off all the old patchy anti-foul, filled some deep scratches and decided it would look a lot better in White than the original Yellow Gel coat.
After following this thread I took a risk and put International Brightside straight on to the gel coat after rubbing it down, rather than use the undercoat, as that appeared to lengthen the drying time.
The Brightside is like water, and the first coat looked like I'd painted it with low fat skimmed milk, so I knew I was in for a few coats.
After reading the drying times related to temperature on the can I put the first coat on Tuesday morning at about 9.00am, the temp that day reached a max of about 13 deg.
On Wed morning at about 07.30am the first coat was transparent, but quite hard with a lot of pressure required to mark it with a finger nail.
So on went another coat
Through the week I've added another coat each morning at about 07.30am after making sure the surface was moisture free from the night.
The last coat(5th) went on this morning, and having checked it about 6.00pm it was hard to the touch, but quite easily marked with a nail, even after the temp today hitting 26 deg.
Obviously its got warmer each day as the week has progressed, and I've been lucky to have no rain. I noticed that each coat appeared a little softer the next morning than the previous coat had, which is to be expected I suppose because of the build up of layers still 'going off'. But so far it looks good, and I'm expecting it to be hard in a couple of days.
RIBBED For extra pleasure.
Member of the ebay Blue RIB cover club.
Member of the Bombard 380 Aerotec club