> This weekend I finished painting my Chesepeake (below waterline) with a
> single component silicone alkyd enamel marine paint. Following the 3rd
> coat I find the paint very delicate - scratches very easily and in some
> areas where the paint is a bit too thick it seems soft. Would a linear
> polyurethane clearcoat or varnish polyurethane strengthen the paint and
> make it stronger when sliding on a vehicle roof rack or dragging on
> shores? Will this paint harden any more as time passes? Thanks.

With multi-coats of paint you have to be aware of dry times. Don't hurry. In cool environments, usually below 70F, you have to lengthen the dry times, sometimes doubling or tripling them.

It sounds to me that you have not allowed one coat to cure before applying the next. If you do this a couple of times you will have a problem. You could try putting some heat into the kayak with a small heater or some lightbulbs. This will cure the paint from the inside instead of having the surface cure and the inner coats still uncured.

As for putting a polyurethane over it you will still have the problem of the uncured paint underneath. As each layer relys on the previous layer for strength your paint will peal off much as it is now.

Wait and see if it will set and if not strip it off and redo it.

Not much help I guess!

Ian