Remove single pack paint applied to two pack substrate

[WhiteDwarf]

I need to repaint a plywood dinghy (Jack Holt Heron). The original but tatty paint job was two pack Northane. It was overcoated with single pack International.

To apply another coat of two pack, I need to remove the single pack.

Can anybody recommend an alternative to getting down and sanding it?

Thank you.

[Mr Efficiency]

How about paint stripper ? You may get lucky and find one that attacks the one-pack ,and not the underlying 2-pack. Maybe a pressure cleaner to assist the process after the paint stripper has softened it up, scraping is hard work. Or just stick to the one-pack recoat, saves a lot of work and will look and perform well. I'd imagine dings in ply won't be any less noticeable in 2-pack.

[gonzo]

Pressure cleaners have to be used very cautiously on wood. They can break the wood fibers and glue joints. A stripper may work, but you should consult the manufacturer for compatibility. It could deteriorate the Northane and make the finish coat blister and peel.

[michael pierzga]

Just sand , prime and paint.

[Mr Efficiency]

Originally Posted by michael pierzga

Just sand , prime and paint.

That would be the smart idea, I think, but sounded like he wanted to return to 2-pack. Trouble with that is the surface would need to be 100% free of the one-pack or turn into an ugly mess.

[michael pierzga]

Not always... take some two part thinner on a rag and wet an area of old paint. if the old finish wrinkles you must remove...if not sand prime paint.

[Mr Efficiency]

Originally Posted by michael pierzga

Not always... take some two part thinner on a rag and wet an area of old paint. if the old finish wrinkles you must remove...if not sand prime paint.

So there are one pack paints that aren't attacked by the two-pack solvent ? Any idea which type(s) ?

[WhiteDwarf]

Mr. Efficiency, you are spot on, I plan to go back to two pack. If I sand off the single-pack, I will have to completely eliminate the material, including any particles left behind in the abraded surface.

Michael's suggested use of thinners, might achieve the necessary removal.

Thank you, all for your suggestions.