thinning polyurethane paint

[meboater]

I am painting some of the deck of my boat. Parts of it have a non-skid patern in the fiberglass. Not coated with a non-skid paint, just a cross hatch patter.

I am using Brightside One-Part Polyurethane, and believe it will work best very thin, multiple coats. I am also planning to use brush only. I am hoping this will keep from gunking up the grooves.

Two questions:
Any advice on technique?
What kind of thinner can I use? The closest marine store is a 3 hr round trip, and I am wondering about hardware store thinner.

Thanks.

HH

[Ulladh]

Any polyurethane will be a temporary finish, repaint in two or three years.

If the gelcoat finish can be restored, search posts from "mainsail" for methods and products, then this would be a better approach.

If the gelcoat is beyond restoring and you can live with a good enough finish that will require repeating in a few years then prep really well, light sand, tape off or remove deck hardware, and use recommended primer.

I would not thin the polyurethane but if you do, only use the recommended thinner formulated for this application.

Hand paint with brush; paint a rectangle within a forearm sweep, 18" square, then cross hatch paint strokes within, move on to next area and repeat. Don't over brush each area. Sweep the paint brush from your shoulder or elbow not wrist for a more uniform brush stroke, and don't stop until the entire area is complete.

This is a least worst finish option.

[mikehoyt]

Thinner Brush - Brushing Liquid 333. Spray - Special Thinner 216.
Thinning Thin if necessary with Brushing Liquid 333 to improve brushing characteristics.

Check out yachtpaint.com - the website of International and Interlux paints. Go to product guide and from there look at product data sheet. All the pertinent information is there. The above is from that.

Interlux is great for this information.

I suggest you use a foam roller rather than brush and then use roll and tip method. End result is much nicer than brushing

Mike