More WB Pigmented Topcoat Questions

[Hugh MacDonald]

I’m currently spray-finishing the millwork that I made for a powder room/mudroom suite that I built. The panels and mouldings were primed off-site using Zinsser BIN Shellac primer. I’m now topcoating them on-site with Target Coatings EM6500 pigmented “lacquer.” (A few pics attached to provide some context, which can always help. Forgive their poor quality.)

For a few reasons, I’m not getting as good a result as I’d like—namely the surface is ending up somewhat rough. I believe this is mostly due to the combination of spraying a waterborne, on site, in winter. I can’t open the windows and doors wide enough to exhaust the overspray sufficiently without it become too cold. Consequently the overspray comes to rest on the wet or tacky coating, giving it the roughness I’m witnessing. Being a waterborne the overspray dries quickly in the air (which is very dry, as it’s winter) and lands on the rapidly drying surfaces. Being a waterborne it doesn’t have the ability to resolve or dissolve that overspray to allow it to “melt” in.

It’s not a horrible result, ultimately, and it looks good. But running one’s hand over the surfaces (which I am wont to do) doesn’t reward one with that reassuring smoothness. Having read through this finishing forum it seems that the issues I’m having (along with some other related issues) are very common. There is no shortage of waterborne-pigmented-topcoat threads. But I have a couple specific questions that I just can’t answer myself, and hope some of you guys might have the experience (that I don’t have) to be able to opine.

Firstly, do you think General Finishes coatings are that much better that they justify the (sometimes significant) extra cost over similar coatings from other brands? By better here I mean: easy to spray/more forgiving while still producing an overall excellent result. Maybe not the toughest, most durable coating—for that you’d need to go with a 2K polyurethane. Maybe not the clearest finish (in the case of clear topcoats)—for that you’d probably need to use real lacquer. But still an overall great-looking finish that provides the level of protection/durability you need for that application.

I’ve sprayed Target Coatings almost exclusively, specifically their 9000-series polyurethane, their conversion varnish, the 5000 primer/filler, and the 6500 pigmented topcoat. I have wanted to but have not sprayed the 6000 WB lacquer which seems to be a common favorite. I started spraying Target mainly based on positive reviews here and continued with them because of familiarity with their lineup, fair prices, quick shipping, and the fact that they worked well enough.

But while they’ve worked well enough I’ve never been blown away by the Target finishes—not in the way that people who use the General coatings seem to respond to their products. Here and in other forums I’ve seen a lot of “I’ll ONLY use General Finishes” and “After having problems with Coating X, I tried the General product and it was so easy to spray and the result is perfect!” I just don’t consistently see people talking that way about other coatings.

The General products, however, cost two or three times as much as analogous products from other brands. General’s white pigmented poly, for example, is around $100 a gallon, sometimes before, sometimes after shipping, depending on the source. (It’s interesting that their black pigmented poly is significantly cheaper.) Meanwhile I recently bought Target’s 6500 white pig lacquer topcoat for about $45/gallon, including shipping, when they were running a promotion, which seems to be pretty much all the time. Other examples of this price differential are easy to find.

So are General’s finishes better? Of particular and practical interest to me right now is whether the General WB pigmented poly is “better” or easier to spray and more forgiving than the Target WB pig topcoat, or other topcoats? Because I’m thinking that a finish, under normal conditions, that is easier and more forgiving to spray and always results in great results even for people who don’t have lots of experience or technique will maintain those characteristics in less-than-ideal conditions. A finish that’s easier to spray/more forgiving would possibly allow me to get a superior result. And it would be worth it to me to pay more for that. I’m well aware of the situations where you just “can’t afford” NOT to use the more expensive product, because it is superior, and you’ll likely find yourself buying it anyway after trying to save money by buying the cheaper product. In the end you’ve spent a lot more money (and time) than you would have if you just went with the better product from the start.

Part of the answer to this question is inevitably subjective—if you get good results with the finish, you feel comfortable with the finish, and you feel like you can afford the finish and it’s worth it, then sure, it’s justified for you. But I’m more interested here in a more objective take on the issue, from people who have used a variety of coatings, might be minimally familiar with the chemistry, and can compare apples to apples and apples to oranges.

And I’m not just potentially interested in General coatings. Any waterborne pigmented coating that you’ve sprayed and really like (or heard very positive things about) is of great interest. I’ve come across a few products that might be promising but information about them is sparse. Among others I’m talking about AcromaPro Akvatopp Waterborne Pigmented Topcoat; Valspar Zenith WB Pre-Cat Pigmented Topcoat; Chemcraft Aquawhite Acrylic Pigmented Topcoat; ML Campbell’s Agualente; and Sayerlack’s Waterborne Topcoat for Interiors.

Some of those might be even more expensive than General, or impractical to get ahold of, especially in small quantities, but they’re still of interest.

Finally, because of the conditions I’m spraying in, it also eventually occurred to me to consider a finish that’s less dependent on weather conditions for getting a good result. Which basically means solvent-borne finishes. I have no experience spraying anything but waterbornes—with the exception of shellac primer, which among ALL the things I’ve sprayed is my favorite. You can spray it light or lay it down heavy. It sands better than anything else. I saw it mentioned by John TenEyck as an option in another recent pigmented-topcoat thread, which encouraged me. By itself it’s definitely not durable, but under a clear topcoat would it be protective enough?

Sorry for the length of this post, but I wanted to cover all bases. Hopefully some of the responses will help me and the many others who are interested in waterborne pigmented topcoats now and in the future.

[John TenEyck]

Lots to chew on with this one, Hugh. I've never used TC's products; I've been satisfied with GF's products well enough that I haven't looked at many others. GF's products are expensive, as you point out. The good news is they work very well. However, some of them work better than others, and none of their products are the perfect choice in some applications. What you are doing right now might be one of those applications.

I've sprayed about 2 gallons of the Enduro White Poly. I sprays beautifully straight from the can with my pressure assisted HVLP conversion gun. But you definitely need good ventilation to carry away the overspray or you will get the rough surface problem you are having right now. Enduro White Poly isn't the answer to your problems unless you provide ventilation, and if you do that the TC product will work just as well. I think you would be fine if you put a fan in the window while you are spraying to get rid of the overspray. As long as the room and finish are above 65 F, or whatever TC says it needs to be, and you close the window after you finish spraying, it should cure fine.

I think EnduroVar is about the best non catalyzed clear coat I've yet used, but it was a PITA to spray well until I got a pressure assisted gun. I had constant problems with orange peel if the coating got just a little too thick to pinholes from the coating being just a little too thin. Once I got the PA gun, heaven, it sprays beautifully.

GF's High Performance Poly is about the easiest thing I've ever sprayed, and it looks beautiful to me, but it's not very durable chemically so it has limited utility for me. Their Enduro Clear Poly is a much more durable product, sprays just as easily, and looks just as beautiful, but doesn't have the UV package that HP Poly does. Nothing's perfect.

I have wanted to try SW's Sayerlack and Kem Aqua Plus and now that they are available in 1 gal cans I have no reason not to. One well respected member here is very high on Kem Aqua Plus. On the other hand, a pro friend of mine recently gave me access to buy GF's products through his business account and the savings are substantial so I have less motivation to switch.

Back to your current problem. If you can't ventilate the overspray, or try it but still have the roughness problem, then you might consider switching to BM's Advance paint. It sprays just as nicely as the Enduro White Poly for me with my PA gun. It dries VERY slowly; hours instead of minutes. It cures even more slowly; weeks or months instead of days. But you won't have problems with overspray. I'm not sure you can or should switch to it on what you've already finished, however; I see it more on what still needs to be done.

As for shellac under clearcoat being durable, it has been for me. That's a very common finishing recipe for me. Dye or stain, Sealcoat shellac, topcoats. Never had a problem with adhesion.

John

[Hugh MacDonald]

Awesome, John, thanks for the tip on the BM Advance. I did not notice it when I was looking at their products. The BM paint I did see getting attention was the Satin Impervo. I had previously seen the waterborne Impervo mentioned as a quality 100% acrylic that can be sprayed, and the other day I read a review of the solvent alkyd Impervo saying that it brushes so well it looks sprayed. Not sure if I believe that completely.

I just know I've never had that kind of "Wow" experience with Target's finishes like people seem to have with General. Though I do really like the BIN primer. The only thing I don’t like about it is the cleanup. That’s why I’ve been so interested in finding a waterborne pigmented coating that’s more forgiving to spray and has the ease of water cleanup. I suppose the WB chemistry is going to be somewhat similar across brands. But, still, my experience being so limited, to just a single product, I figured it’s not that unreasonable to think another finish out there might work better for me. It’s just a matter of finding it. And it’s a bit impractical—right now anyway—to go out and buy a can of everything and test it all.

[Jim Becker]

I've never had a "rough" issue with Target Coating's products and overspray is pretty much dry before it hits the floor. Whatever is suspended in the air gets collected quickly by an overhead air cleaner before subsequent coats are sprayed. I do pay attention to temperature for all finishes as being below the manufacturer's stated range can cause issues and that applies to all finishes.

I unfortunately cannot contrast Target's products with General's as I haven't used the latter. Yet. I do plan on that in the coming year. I have used BM Advance, but my gun doesn't spray it well. Advance is very much temperature sensitive since it's an emulsified Alkyd (oil) finish with a water carrier. The water has to evaporate after it transports the paint to the workpiece and then the Alkyd finish cures normally. Water is used as the carrier to considerably lower VOC. If you've used Target EM2000, Advance is a similar finish, but in a tint friendly paint form. The other water borne tint friendly acrylic I've used, albeit a long time ago, is from Fuhr. (Who appear to now be part of CCI)

[John TenEyck]

Hugh, BIN shellac based primer is a snap to clean up if you hit it with about 20% ammonia in water and then hot, soapy water. After that, just an ounce or two of DNA or lacquer thinner and it's Spic-N-Span clean. But if you want a WB primer, try SW's. I can't remember the name right now; something like "wood and wallboard". Its viscosity is really high however, like Pro Classic, so you need a pressure feed or airless to spray it well.

John

[Hugh MacDonald]

I know, the cleanup for the BIN primer isn't that bad. It's totally irrational, but for me spray-finishing can cause some anxiety. I don't know if others experience the same thing or not--I think it comes from a fear of being able to ruin in one fell swoop something you've spent a lot of time trying to get perfect. I sort of dread it when I know I have to spray and then the spraying process and cleanup feel really hectic, like I need to rush or the finish is going to dry in the gun and I won't be able to clean it. It's irrational because in reality it's never that bad--the project looks good and the cleanup goes fine. With more experience it's gotten better, but this project was the first time I'd sprayed a pigmented coating, and when I started it and was feeling anxious I thought if I could use a waterborne primer then at least the cleanup part of the process wouldn't cause me as much worry.

It's not something you think about, but as I sprayed the BIN more I also actually got better at cleanup, so I could do it with less time, materials, and aggravation. I've always used DNA for the cleanup, but you're saying you can use ammonia 20% in hot water, and then a wipe-down with DNA at the end?

Part of the reason I raised the issue of the primer in my last reply (though I didn’t continue because I didn’t want to inflict on everyone another extremely lengthy post, like this is turning into) was that it provided a great example of a General product that gets almost incredibly good reviews but also costs much more than comparable primers—their Enduro White Undercoat. I was looking for a sprayable primer that worked well for sealing/filling the edges of MDF, and I ended up doing a good bit of online research in that pursuit. The most interesting thing I found was a thread (in another forum) devoted to that issue in which one of the respondents very helpfully conducted a small study of different methods, and posted images of the results. Among the various products one very clearly outperformed: a General Finishes product, as you might have guessed, the Enduro Sanding Sealer. (He brushed the sealers. I’ve attached the photo, and you can find the thread here: http://www.woodworkingtalk.com/f8/fi...f-edges-49113/)

I looked at the General sanding sealer (which is typically well-loved) and through that found the Enduro White Undercoat, which General recommends for using under pigmented white finishes and is actually supposed to be formulated for use on MDF. Universally adored, but at $80–100 at least twice as costly as BIN or the Target 5000 Primer/Surfacer/Filler that I ended up trying. That worked OK but not great and it doesn’t sand as well as the BIN. So I remain curious about the General Enduro Undercoat, while I’ll likely stick with the BIN.


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[John TenEyck]

Yes, after spraying BIN shellac based primer I throw the gun, cup, everything in hot water with about 20% ammonia in it. Ammonia kills shellac, and it's a lot cheaper than DNA. It won't necessarily get everything out of the gun, however, so after the ammonia bath I soak the nozzle and air cap in a small amount of DNA and wipe the needle, too. Then I put the gun back together and pour that DNA into the gun and spray it through. Then I wipe the outside with a little more DNA or lacquer thinner.

There's no hurry to clean up a gun that you've been spraying a solvent based finish with since it will always redissolve in that solvent. Focus your efforts on spraying well; clean up is stress free. Water based, on the other hand, you have to clean before the finish dries in the gun. No big deal either, really, just dump everything in warm soapy water and then clean up at your leisure. And lacquer thinner will usually remove any finish that dried before you got it into water.

I use lightweight joint compound to seal the edges of MDF. I just wipe it on/into the edges of the part with my finger, let it dry, and then sand it smooth. Cheap and effective. I'm sure the GF primer is a good product; I just haven't seen the need to try it. BIN does a great job after the joint compound has filled the edge.

If you aren't confident spraying your project, practice on scrap constructed in a way that offers a similar challenge. I'm not saying I never have anxious moments, I do and plenty of them, but I try to never do something for the first time on my project. Watch videos, too. I learned a lot about how to spray the inside of cabinets, and face frames, by watching a couple of pros do it.

John

[Walter Butler]

Hugh,

I operate a small cabinet shop, and this summer I had to switch to all waterbornes after too many complaints about the fumes from my solvent-based operation. I tried some of the brands out there- SW's KemAqua Plus, Target 6500, General, ML Campbell's Agualente, Gemini's Titanium WB line.

The winners were Gemini Titanium for pigmented and ML Campbell Aqualente for clear....largely because of customer service (Sherwin-Williams seemed dedicated to never delivering to me, The guy from Target never returned my repeated calls even though they sent me the wrong sheen of EM6500)......whereas Gemini and ML Campbell give me next-day delivery if I get the order in early enough.

No one product performed better than any other, at least from my observation, and it seemed that all of them were prone to the big problem WB's can have:the little pinholes that can develop upon drying. A designer I do finishing for did prefer the sheen and feel of the Gemini (pigmented) when compared side-by-side with Target and SW...so that decision was easy. I know that Aqualente Plus is an extremely durable finish, though I do miss just plain old Aqualente.

I sprayed about 50 gallons of product in 2016....most of that pre-cat lacquers or CV's, but I've probably used about 15 gallons of WB since the switch. My primary gun is a Kremlin AAA and my backup is an old 5-stage Titan with a a Maxxum 2 gun. I have two Harbor-Freight quality gravity-feeds that I use for small stuff. Most of the problems I had with applying WB's were solved by adding 5% DNA to the product, and occasionally boosting the humidity in my drying area (sounds crazy but it works)...I also used to run 25#/30# through my AAA, but with WB's usually start at 20/28 (air/fluid) and fiddle with it if I need to. I also read, "Somewhere," that WB's perform better with HVLPs than they do with AAA systems....if anyone can verify this, please let me know.

Primer-wise, I use the Agualente. I still occasionally use Bin white shellac for small stuff, and I miss the good old days of being able to use it for everything.

Other paints I've had good luck with: BM Satin Impervo, and their Advance....both thinned about 20%. Farrow and Ball makes excellent, expensive paint, and their floor paint sprays really well (again, thin 20%)....I haven't had any luck with their other sheens (their Estate Eggshell never, ever seems to dry). Also, F&B doesn't custom tint, at least to my knowledge.

If you do switch to solvent-based products, you'll be amazed at how much easier they are than WB's. But most shops I know have switched to WB systems...OSHA really, really doesn't like flammable, toxic liquids getting atomized around people. Hope this helps.

[Jim Becker]

If you do switch to solvent-based products, you'll be amazed at how much easier they are than WB's. But most shops I know have switched to WB systems...OSHA really, really doesn't like flammable, toxic liquids getting atomized around people.

I will add to this that most woodworking hobbyists do not have a good, safe environment for spraying solvent-based finishes...and safety should always be a primary factor.