Pigmented lacquer technique?

[yuri]

Guys,
I have a project which will be finished with white pigmented lacquer. I've never did this before, mostly used clear coats (solvent and waterbased) or oils and pretty fluent using them. Anything different (tips and techniques) for that type of finish? I am going to use water based lacquer HYDROCOTE RESISTHAN, white.

[jteneyck]

Guys,
I have a project which will be finished with white pigmented lacquer. I've never did this before, mostly used clear coats (solvent and waterbased) or oils and pretty fluent using them. Anything different (tips and techniques) for that type of finish? I am going to use water based lacquer HYDROCOTE RESISTHAN, white.

The minute you start using paint or pigmented products is the minute you realize you have to a much better prep job to avoid defects showing compared to your clearcoat projects.  Paint shows every tiny defect.  Inspect, fill, sand, inspect, repeat.  Even then you likely will find some defects after you spray the primer coat.  Rinse and repeat until it's as prefect as you can make it before spraying the topcoats.  


Another difference is that pigmented products usually have a higher viscosity than clearcoats. but the datasheet for Resisthane White shows it's exceptionally low at 25-30 seconds #4 Ford cup, lower than many of the WB clearcoats I use, so you likely won't have any problem using your current spray gun and N/N.  If you're using a gravity feed conversion gun, a 1.4 mm N/N set should work well.  

John

[yuri]

John,
thank you for the explanation. As always clear, detailed and right on topic answer.
I'm little bit confused. Am I right, supposing, that pigmented lacquer does not require top clear coat?
As for viscosity, may be they just gave the number for Resisthan without pigment added. Will see once I will open the can.
Though I have spray gun, I am more inclined just to use foam brush for that project.

[Stwood_]

I never top coated a clear after spraying white lacquer.

If your lacquer is not marketed as brushable, you may not want to brush it.
Things change, but I haven't ran across a brushable white yet.

[Cooler]

I am reminded of my first generation Scion XB (2003).  It was an early example of a car with the newly mandated low VOC paints, and I was told it was a water based lacquer. 

The finish, when I got the car, was so soft that I could scratch it with my thumbnail.  A car wash was an invitation to a "brushed finish" car. 

The finish hardened over time and about one year or a year and a half later it was hard enough for me to consider it a successful product. 

Obviously finishes have improved dramatically since then.  But my suggestion is to allow sufficient time for the finish to cure before placing it in service.  The number I hear most often is 200 hours (close to 9 days). 

I do have some items that I finished in oil based poly that are over 20 years old and they have a noticeably harder surface finish than items finished with the same oil base finish with a two week cure time.

So my take is a "full cure" is probably about 80% or a bit more of a total cure, which is an ongoing process that takes significant amount of time.

Be patient.  You did a lot of work to complete the project.  Ten more days will not kill you.

[jteneyck]

John,
thank you for the explanation. As always clear, detailed and right on topic answer.
I'm little bit confused. Am I right, supposing, that pigmented lacquer does not require top clear coat?
As for viscosity, may be they just gave the number for Resisthan without pigment added. Will see once I will open the can.
Though I have spray gun, I am more inclined just to use foam brush for that project.

I was suspicious looking at the viscosity data, too, since both the clear and pigmented products are listed on the same data sheet but only one viscosity.  As you said, you'll know when you open the can.  

I have over-coated with clear but only because the pigmented product I was using wasn't as chemically durable as what I wanted, so I sprayed a coat of clear over it that I knew had good chemical durability.  Otherwise, I never over-coat.  There is an argument that repairing a scratch is easier in the clearcoat than the underlying pigmented product.  I guess if there are only superficial scratches that's true, but for any that go into the underlying pigmented layer it seems like repair would be harder.  Anyway, I don't do it.  

You could try adding about 5 - 6% of GF's Extender to the Resisthane product to see if that will allow you to brush it on.  Obviously only try it with a small amount of product and on scrap first to see it will work and cure correctly.  

As for curing, Cooler, most of the waterborne products I use dry very fast and cure pretty hard within 72 hours.  Full cure takes at least a week, but that's still short compared to any of the OB products I reluctantly use from time to time.  I sprayed a passage door yesterday.  I sprayed a coat of Duralaq Undercoater primer before lunch.  It was hard enough to sand in a little over an hour.  Then I sprayed two coats of Duralaq white lacquer, about 2 hours apart, the last one just before dinner.  It was plenty hard enough this morning to pick up and move.  

To anyone interested, you can buy Lenmar's WB Duralaq acrylic and Megavar polyurethane products at your local Benjamin Moore.  I've only used the Duralaq products so far but they spray and look great, and are real bargain compared to the other brands I use.  Also, BM will custom tint them to any of their 3000+ colors.   

John

[Cooler]

As for curing, Cooler, most of the waterborne products I use dry very fast and cure pretty hard within 72 hours.  Full cure takes at least a week, but that's still short compared to any of the OB products I reluctantly use from time to time.

John

I agree that waterborne products dry fast.  I am not as certain that they cure must faster however.  I think one week of cure is probably all anyone is going to do.  I finished by kitchen counters and started using it 3 or 4 days after the installation.  But I used coasters and mats for about a month to protect the finish.  A similar tactic might work in other situations too.

Interestingly "UV inks" that are used in the printing industry are not UV resistant, but use UV to cure the finish.  There are UV wood finishes too and they cure very, very fast, but from my experience are not as durable as other finishes.

[Kansas City Fireslayer]

John T,

Would you use the WB Duralaq acrylic on bathroom or kitchen cabinets? Would you use it over GF’s white enduro poly?

Thanks,

Damon

[jteneyck]

John T,

Would you use the WB Duralaq acrylic on bathroom or kitchen cabinets?  Would you use it over GF’s white enduro poly?

Thanks,

Damon

Yes and no.  I used Duralaq pigmented acrylic on my kitchen cabinets, but top coated it with GF's Enduro Clear Poly to improve the chemical durability.  Duralaq alone was easily damaged by ammonia cleaners.  





I've used several gallons of Enduro White Poly, but have never clear coated it.  If I did, I'd use Enduro Clear Poly (as long as a test piece to make sure they are compatible turned out OK).  

I have not yet tried MegaVar.  That Lenmar product is KCMA rated, and I'd expect it to do well on bathroom and kitchen cabinets.  

John