BYYB Forums

I'm nearing the varnishing stage for my brightwork (all spars, mast, interior and usual deck fittings like hatches, grab rails, coaming etc.  I've heard the pro-varnish arguments:  more flexible, easier repair, but the cost is a little off-putting: $83/gallon for Z-Spar Flagship varnish.  Polyurethane "spar varnish" like Varthane and others runs less than half that.  Anyone have favorable experiences using the polyurethanes for brightwork?  How about using polyurethane inside the cabin, and traditional varnish outside, on parts directly exposed to the sun?

Dave

Polyurethanes dry fast and cure hard. They are less flexible, but on epoxied surfaces this isn't very important, as the epoxy locks the wood down (assumed encapsulation). The ability to apply three or four coats a day is appealing too. The good stuff will cost just as much as good varnish. I'm paying $130 a gallon for poly. Be sure you get what you need, as the polys are much clearer and have less color then the real varnishes.

Varnish isn't as durable, nor as glossy as polyurethane. It's easy (relatively) to repair and will flex with the wood. The good varnishes will add a lot of color to the wood and they can take what seems like a life time to fully cure.

Polyurethane will out preform even the best varnish, in gloss retention, UV protection, etc., some times by 2:1, but mostly by about 50% as much better. In the sunny Florida climate, good varnish will last a year, before you need to make repairs, polyurethane about 18 months. They both will still look good at these time intervals, but damage will begin to show and if you don't "catch it" when you can, you're screwed and the whole finish and likely some wood will need to be removed, restored and refinished.

Paul:  The poly you refer to that allows 3-4 coats per day is water-based, correct?  What about oil based polys like Varthane Spar urethane?

Dave

I wouldn't recommend any of the water born clear coatings, some of which are partly polyurethane. Most of these water based systems are in their second generation and much better then the first products that showed up over a decade ago, but they still suck.

The word "spar" in the name of the product usually means coloring. A "spar" urethane would be regular urethane with amber color added.

The polyurethanes I'm using dry in minutes and can be sanded in hours. I don't recommend these for novices, as they literally dry while they come out of the gun, so some skill and considerable prep is required. You can't roll and tip these finishes, though there are some brands that permit slower activators and wetting agents.

Paul:  My brightwork is all epoxy encasulated.  Would you have a problem using an oil based poly like Varthane's Spar urethane or Minwax's Helmsman spar urethane?  IO don't think I'm up to the pro stuff you use!

Dave

Minwax products suck, don't even think about using them, unless it's aunt Millie's rocking chair and you don't like her all that much. Valspar products I don't have much information about, just that it's also a DIY type product and probably about the same as the Minwax stuff (I'm assuming).

System Three polyurethane is getting popular. Epifanes PP varnish is well liked. Pettit Z-Spar and Interlux Goldspar or Schooner are also well used. Bristol Finish is also very good and I use it fairly often (they're local to me)

The home owner stuff does a decent job, but you'll be recoating it sooner and damage can occur faster with the Minwax type products. Most of the real marine clear coatings will cost about $20 to $40 a quart and some of the fancy stuff can cost a lot more. Which you elect to use is more about comfort level and experience.

Thanks, Paul.  I talked to a local boat guy today.  He uses Petitt Captain or Flagship.  He felt that 3 coats over my 3 coats of epoxy were enough for a trailered boat kept in a garage.  What do you think?

Dave

Three coats leaves no margin for error, wear or UV degradation. If the boat is kept indoors and doesn't have any sunlight (including reflected) touch the surface, yes, 3 coats will do.

It doesn't take much time at all to damage a coat or two of varnish. One missed step, one dropped what ever and you've now got a direct path to the stuff under it, which you really don't want to have to fix or refinish.

I consider 3 coats a tease. The bottom line with clear coating anything and the outdoors, is film thickness with effective UV inhibitors. The more you got, the better off you'll be. 3 coats is like a hot fudge sundae that has just a drop of hot fudge, slithering down the side of a scoop of vanilla.

Paul, Please remember that some of us are on diets trying to lose a bit of weight.  Your hot fudge sundae comparison lead to me eating a dish of the stuff at 4 am.    Actually after reading your comments I will head to the shop later this morning and add a couple more coats to my oars and tiller handle.  Those are the only bright work I on my boat.  Got lots of varnish left, don't take much for 2 oars and a tiller handle, so may as well make use of it.

Paul:  Thanks for all the great advice!  I've checked out Bristol finishes, and although the price is huge, the advantages may be worth it.  Is it true?  No sanding between coats?  One hour to recoat?  Seems to good to be true!  Their website claims 133 sq. ft/gallon with 6 coats.  Can I brush it on, roll and tip or must it be sprayed?

Sorry for all the questions but before I invest almost $400 for 2 gallons I want to be sure I know what I'm getting!

Dave