Bubbles in gelcoat

When I do a gelcoat repair, I tend to find little pock-marks in the gelcoat as I am rubbing it down. I am assuming these are little bubbles that I am sanding through. How can I stop this? I am mixing the GC and catalyst thouroughly and the repair area is spotless and dry.

From experience, it is very difficult to stop this from happening. I think they are caused as the gelcoat goes off, the quicker you make it go off, the hotter it gets, the worse the pin holes are. If you have the time make it go off slower but this isn't fool proof.

As Mr Merlin says, you will probably have to re-fil them after. I'd recommend filling the problem area with gelcoat and fillers and then roughly sanding it to shape. Then paint on a couple of really thin layers of gelcoat with a brush. This can then be wet and dried, and then polished to perfection!

Practise makes perfect, and the longer you spend, the better it will look!

A man who knows about these things told me that the best way to avoid small bubbles in your gelcoat is to brush it on. Apparently, the action of brushing chases the bubbles out of the gelcoat. My repairs have been a lot simpler since I took his advice.