Epifanes PP Varnish

[screwfix]

I'm currently helping to varnish a large yacht with Epifanes PP varnish as a build up, prior to top-coating with several coats of Awlbrite varnish.

The areas being varnished are rather large, consequently we have been rolling on the PP. For reasons beond my control we have not been 'tipping off' with a brush, neither have we used very much thinners, about 5%. Varnish has been applied in cold conditions, between 10-15 degrees centigrade.

My concern is that the varnish has 'orange peeled' which has not caused the owner any undue concern. However, when we block sand the timber we have to take off so much varnish it seems criminal. I feel part of our problem has been caused by not tipping off after rolling and I also suspect that insufficient thinners has played a part in the cratered orange peel effect. Incidentally we have used Epifanes PP thinners and roller sleeves intended for epoxy varnish.

I wondered if anyone has any advice on this matter, many thanks.

 

[Mirelle]

I think you are right.

I have seen this happen in just the same conditions on a far smaller scale with my son's Firefly - cutting back took an awful lot of varnish off.

Definitely more thinner, warmer conditions if at all possible, and tip off for sure.

 

[Peterduck]

It is my understanding that the 'orange-peel' effect is the result of applying too thick a coating, resulting in different parts of the coating drying at different rates. Not 'tipping off' would have exacerbated the problem. I agree with all of Mirelle's recommendations. I am also curious about the use of two different brands of varnish. I suspect that this may also give you grief when you come to that stage of the work. It is usually better to stick with one manufacturer's products for the whole coating system.
Peter.

 

[screwfix]

Thanks for your comments, I'll try to convince the person paying for the varnish to tip-off, and go for a little more thinners.
If anyone has any other comments I'd love to hear from them.
Incidentallly Epifanes technical manager agrees there is no harm in using Awlbrite on top of PP although I must agree I don't see why we don't use Awlspar, the Awlbrite build up.