Linear Polyurethanes??

[matt2]

I am going to be doing some topside painting using a 2 part polyurethane paint. I have painted with International "Perfection" and "Reaction" paints before with mixed results. (Roll & tip)

The Reaction was not high gloss and the Perfection surface was glossy in parts and not others. (Yes I did a lot of prep.) I read later in mags about "Linear" polyurethanes with special leveling agents that are supposed to produce excellent results. I am about to do it again and hopefully use my past experience to get a better result this time.

Now this brings me to the crunch questions, which I hope someone knows the answers too.

Firstly, what Linear polyurethane is the absolute best for super high gloss, long lasting using roll and tip?

People rave about Awlgrip, but which one and what application technique (brush+roller or spray)?

Are these International, Interlux or Awlgrip paints "Linear" polyurethanes?

What is the International "Interspray 900" which says it can be used with a roller & brush and is "premium" and "produces an extremely high gloss" where as "Perfection" is advertised as producing simply a "high gloss" and no mention of "premium", though there is on the Awlgrip website?

Are the International "Perfection" & "Reaction" paints the same as the Awlgrip products (Awlgrip HS, Awlcraft 2000)? (Interlux, International & Awlgrip are all owned by the same company)

What about other paint brands like, DuPont Imron, Sterling and Pettit Challenger System.

What 2 part polyurethane do people use for the deck?

[Maine Sail]

Perfection is a 2 part polyurethane and according to Interlux trech support is not a linear polyurethane. The linear term is a description of the curing and cross linking process. Awlcraft 2000 & Imron are Acrylic urethanes which can be buffed & polished after application where Awlgrip and other LPU's should not be. Awlgrip is a polyester based LPU.

Awlgrip will be the most durable on a deck as would Sterling or Alexseal which are also polyester LPU's. Awlcraft is not a good product for roll & tip and neither is Imron IMHO.

Awlgrip is the most durable paint made by Interlux/Akzo/Awlgrip. Perfection is good DIY paint but not as durable as Awlgrip and Interlux says it should not be buffed.

The best way to get the glossy finish you want will be to spray though I have seen some excellent 10 footer results (looks great at ten feet) with Awlgrip/roll & tip...

[matt2]

Thanks Maine Sail.

Did you roll & tip or spray?

What sort of results did you get (I'm guessing pretty good)?

So from your post, Awlgrip (Polyester LPU) looks good.
Would that be Awlgrip HS or Awlgrip Topcoat?
According to the product data sheets:

Awlgrip Topcoats G/H - A two part polyester, light fast, aliphatic LPU. Cannot be waxed, buffed or polished. (I think this is the one you mean when you say "Awlgrip", yes??)

Awlgrip HS Topcoat - A 3 component polyester polyeurethane, high solids, low VOC(Volatile Organic Content) polyurethane coating designed to provide premium gloss and distinctness of image. (Does not say whether it can be polished?) (Not linear I think)

I am tempted to spray but a big issue I am aware of is that it can be deadly/dangerous if you breath it or get the stuff in your eyes or on your skin. So I would need to wear a positive airflow face mask. I don't think the results would be any worse than roll & tip. Given the enormous effort needed in preparation, I want to get an outstanding result, i.e. better than last time.

I also want to be able to repair any scratches or gouges easily, and I want it to last.

So from what you have said looks like for either spraying or roll & tipping that Awlgrip Topcoats G/H is a good choice?

[matt2]

Anyone clarify these final points?

[tommays]

1. Anything in the instructions that was correct was just a mistake ,like Perfection sprays really well thinned 10% and if you follow the 25% to 35 % it is crazy thin and runny



2. You can can brush in a bit of paint on a gouge BUT it will be a 10' repair

3. When you go down the spray road its not real happy about doing coats 24 hours later due to the high gloss finish ,It wants all the coats hot linked OR wet sanding between coats

4. Auto paints like PPG DCC are much easier to work with BUT i don't know how they will hold up



5 If you don't have a LOT of time driving a spray gun this is a TOUGH way to learn and good equipment cost a LOT of money

[matt2]

Originally Posted by tommays

3. When you go down the spray road its not real happy about doing coats 24 hours later due to the high gloss finish ,It wants all the coats hot linked OR wet sanding between coats.
5 If you don't have a LOT of time driving a spray gun this is a TOUGH way to learn and good equipment cost a LOT of money

The problem with roll & tip is that even if 97% turns out OK, it is very difficult to fix the other 3% after the event.

I have used spray guns before but not in places where it really matters.

The main issue is avoiding excess spray and getting runs or sagging.

I was thinking of practicing on some glass etc.

Curious what successes others have had.

[tommays]

Matt

I use to own a bicycle frame building company and painted my frames with PPG DCC two part poly which is like like Imron


NEVER HAD A PROBLEM with anything because you could follow the instructions and they were CORRECT


Apparently while the marine paint is GOOD paint a LOT of what they have done to make it look like it has clear coat makes IT A PITA to work with.

And the instructions pretty much SUCK

You have NO TIME AT all when spraying to stop long enough to sneeze before there is and issue with cutting back in to were you stopped painting

[matt2]

Excelent result!

Originally Posted by tommays

I use to own a bicycle frame building company and painted my frames with PPG DCC two part poly which is like like Imron

So you have experience spraying by the sound of it.

Originally Posted by tommays

You have NO TIME AT all when spraying to stop long enough to sneeze before there is and issue with cutting back in to were you stopped painting

Yes I understand, but the same thing applies to roll & tip.

Could you please describe your spray technique and the equipment you used?

Also I am curious what made you choose "Perfection" over Awgrip or any other paint?

[tommays]

IMHP Perfection is the consumer line of paint and Awgrip is the pro line and when its all said and done there is no BIG difference

I went with Perfection because it has a BETTER system to prime Alu parts like a mast .

The Awgrip uses and acid wash system that requires a lot of rinsing with water which is a big problem in MY CASE and i think in painting masts in general as it is a PITA to get a mast dry enough for the next step after you hose it down because of all the places that trap water


I sprayed with a SATA mini jet with a 1mm tip which is a really good size for things like masts because of the small fan size really cuts down on over spray

I thinned the paint 10% buy volume after waiting the 15 minutes when mixing the A and B , YOU NEED really good containers with volume marks i used lab 500,150 and 50 ml lab glass ware which has Volume markings

We found that 50 PSI at the wall mount filter system with a 35' hose gave good atomization to lay down a smooth coat the tip was pretty much WIDE OPEN

Again the real issue with spraying is the two hour pot life because the best practice is to do ALL the paint in ONE session and buy the time your ready for a second coat the paint is past its pot life and NO GOOD

So you have to have a good plan in place and it takes about ONE MONTH for the paint to get COMPLEATLY DRY

Yea it looks pretty good after a week BUT its a month for a FULL cure

[matt2]

Did you wear a positive airflow mask, or a simple filter?

Pardon my ignorance but when folks say "Awlgrip", which one do they mean Awlgrip Topcoats G/H (LPU) or Awlgrip HS Topcoat (A 3 component polyester polyeurethane (Not LPU))?

What spray gun would you recommend for the hull and the deck?