Polyurethane Varnish / Polycrlic / Fuel Proof??

[Rob_P]

After a lot of thought I have decided to stain the cabin sides on my boat. So far I have got a can of Minwax Polyshade. Its a combined stain and polyurthrene. On a test piece, two coats give a nice stain and finish, but for me I wanted a little more protection & thought I could give it coat of Brodak's Butyrated clear dope (fuel proof over the top to really seal the finish).
The bad news is that the dope seems to eat into the Polyshade. I have tried a coat of conventional polyurethene varnish over the top of the Minwax Polyshade and that works fine.

My question is - How permanant is Polyurethene varnish?
Could I do a really nice finish and then find it need re-sanding and re-applying in three years time? Is there a better alternative?

I have seen cans of Polycrylic and suspect its similar to varnish but I'm not sure what the difference is. - Any ideas?

Finally when I come to do the decks of the boat I have some lime planking 10mm x 1mm on order. I was going to seal over the decks with the Brodak clear dope but as this is not going to work for the cabin sides I need a new product to "varnish" and seal the decks. Hopefully the same product as the cabin sides.

Any suggestions?

Rob

[Kmot]

I built a huge flightbox, and covered it with Minwax single stage stain and poly. It is fuel proof. I have a 1 gallon can of nitromethane fuel mounted on this flightbox and I have spilled quite a bit. It has never affected the Minwax.

[green-boat]

Polyshade is a water based polyurathane with a water based stain added. polycrylic is also water based just without the added stain.

Polyurethane comes in two versions, water based and solvent based.

[Rob_P]

Thanks for the input.
When you see model boats at exhibitions / shows and you see wood with a pefect near glass finish, is it likely that it would be a polyurethane varnish?

Would you use a polyurethane varnish (water based or non-water based) on your boats ?

The reason for my reservation, is that we used to have a sailing dingy (kept out side but with a cover) and every spring we would have to sand back and re-varnish the decks.

Admitedly the model will be kept in a basement and make perhaps 12 trips a year to the pond so I'd hope that once varnished it would stay looking as good as the day it was finished.

Rob

[green-boat]

My mistake, me bad. Polyshades is a solvent based poly not water based.

Sorry.

[jmolwitz]

For the most part all nice looking poly jobs are the solvent type . Typical solvent base poly is about equal to 2 part epoxy in chemical resistance and hardness .

Nothing lasts on boats with water working from behind and the sun (UV light) from the top . Keep your sailboat in the garage that will work :)

I am a painter by trade 20yrs and have read many spec sheets , and compared materials . Good luck

There are some new ,ish Called Waterborne poly's that floor guy's like Pacifica and trek . they are very hard and can be recoated a few times a day .