Comparison Test of Water-Based Finishes

A cabinetmaker subjects six water-based urethanes to side-by-side stain-resistance testing (and shares his results). July 8, 2005

We used Enduro’s waterbased polyurethane for several months during 2004 until we noticed that the top edge of the doors on the sink cabinets appeared to be water damaged at two customer’s homes. We decided not to simply depend on someone telling us that their product was durable or that it passed KCMA testing, so we performed our own tests.

We inquired on this forum what water based products other people liked and ordered samples of VanTech’s Van Aqua 247 sanding sealer and 485 topcoat, Breakthrough’s Clear Advantage sanding sealer and topcoat, Fuhr’s 375 used for both sanding sealer and topcoat, SDA/Craft’s Aqua Pro and sanding sealer, and Enduro’s polyurethane and sanding sealer.

We applied one coat of sanding sealer and two topcoats of each product on maple. All of the products laid down nicely and left a smooth finish. The Breakthrough was particularly smooth, but that appearance may have been a result of its satin finish having less sheen than the other products.

Stain test: We allowed these samples to cure for one week and then applied Bacardi, mustard, Windex, orange cleaner, balsamic vinegar, and Ajax mixed with water. After 24 hours we washed these products off and noted that the results varied quite drastically.

The Enduro poly, which had started showing signs of destruction within a few hours of application of the solutions, was stained by all 6 products. And a couple of the products had darkened the wood underneath the finish.

The Van Aqua showed stains (some slight) from all of the solutions and there were small crackles in the finish where the Bacardi had been.

The Fuhr 375 showed light stains from 3 of the solutions and left a dark stain from the orange cleaner.

The SDA/Craft Aqua Pros showed very light stains from 5 of the products (all but vinegar). The mustard stain was lighter than that left on the other finishes. The Windex stain was the worst of them but still not very severe.

The Breakthrough Clear Advantage showed only 2 stains – mustard and orange cleaner. The orange cleaner seriously marred the finish, though.

Edge test: We placed all the wood samples on a damp sponge for 24 hours. The Enduro, the Breakthrough (surprisingly, considering the exceptional results of the stain test), and the Van Aqua all failed this test. The finish on the edges completely separated from the wood or raised up into crackles.

The Fuhr and SDA/Craft products held up well to the edge test with just a tiny bit of the corners appearing to have water get underneath the finish.

Conclusion: Overall, I think the Fuhr 375 and the SDA/Craft are solid products. We’re going to go with the SDA/Craft as we are located in Southern California and they’re close by. The Fuhr gets too expensive for us once you add on shipping, as they do not yet have a local distributor.

I’m thinking about putting all the samples in the dishwasher to see how they hold up to a ridiculously hostile environment, but I don’t know that I want to trash the results of my other testing.

P.S. I also considered testing a Gemini coating, but I had such a hard time finding someone who even sold it (and they were on the other side of the country) that I gave up.

Forum Responses
(Finishing Forum)
From contributor D:
Interesting evaluation. I have a few questions on the test. What was the dry mil thickness of the finishes and did you apply them uniformly or to each manufacturer's specs? What was the amount of time that they were allowed to cure before testing? Did the time left to cure meet the time of the manufacturers' specifications?

I did a similar test a few years back between SDA duraVar, Vantech 482 and a door that came from a leading national cabinet company that was a catalyzed finish, but I do not know the brand. Both wb finishes outperformed the factory finish in that case and neither caused any problems. I did mine a bit differently, as I took 5 ml of the following products: isopropyl alcohol, acetone, lacquer thinner, denatured alcohol, Lime Away and hydrogen peroxide and laid the panels flat, then poured the products on them and let them sit until they were evaporated in my case. Both passed with no problems. I like your sponge on the edge test.

From contributor L:
I had the same problem with the Enduro poly on door edges and quit using it several years ago. I talked with them about it and they said it was our finishing, so we switched to their suggestions and it happened again. I called again and they suggested we use their crosslinker, so we did and it happened again. We switched to Ultrastar and didn't have that problem, but we tried the Sayerlac and like it better. This is an Italian water based finish (the au468 sealer and the az5720 topcoat). We haven't had any problems. I might have to try your testing method with it.

From the original questioner:
We applied 3 coats of all finishes: 1 coat sanding sealer and 2 layers of topcoat. I don't use a mil thickness gauge, but all were sprayed the same so they should all be the same thickness.

All finishes were allowed to cure for 7 days, which is the longest cure period listed on all of the manufacturer's containers. This appears to be an industry standard for cure time. It's funny that your test of Van Tech and ours was different. We did test different products, though, so maybe that is the reason. We asked their sales person what product we should use on kitchen cabinets and we didn't want to add a crosslinker for safety reasons. He pointed us to the 485.

We were very unhappy with the Enduro poly. When we called them about the problem they kept telling us that it was just a calcified water spot that we needed to wash off with soapy water. It was obvious to us that the water had gotten under the finish. Enduro advertises that their finish was rated best in Fine Woodworking but that article was done way back in 1998.

From contributor M:
Thanks very much for sharing your test results with us. I guess the question is do oil polys hold up any better, or cv's? I can't imagine the lacquers or long oil combos competing, but if anyone has done other testing, it would be helpful to find what topcoat rates out as the most durable.

From contributor J:
Very interesting and I applaud your taking the time to not only test but to inform us about them also. However, I really find it hard to believe that the Breakthrough failed with the moisture test that you performed. I will also do testing. As a side note: I had a kitchen cabinet door that I had finished but was remade because it was of the wrong size. I decided to stick this door outside in a place that was exposed enough to all the elements. It sat out there through winter and part of the summer and I swear the only thing that failed on the door was the stile and rail glue joints popped. The Chemcraft plasticolor did not fail anywhere.

From contributor S:
A one week cure time for testing waterbase coatings is unfair. If you want to give waterbase coatings proper run for their money, then you need to let them cure out for four weeks.

From the original questioner:
We often install our cabinets within a week after spraying them and 7 days was the longest cure time listed by the manufacturer's instructions. So I think it's a fair test. Plus, the test should still be valid as a comparison. The relative quality of the finish should remain consistent. For example, if my test results after one week rank the products in a 1, 2, 3 order, I think the same order would appear if I tested after one month.

From contributor T:
Thanks for sharing your test results with us. I've been happily using Enduro for about a year now, and though I have not had the spotting issue (yet), I'm always looking to improve. I’ve been looking into Target's line and am curious why you didn't use any of their products in your test? I'm not familiar with Breakthrough or SDA Craft. Who sells these products and how do I contact them?

Have you tried any comparisons for scratch resistance? This is my biggest concern with Enduro. I think another concern when choosing a product is their customer service. If anyone has experience with the tested products' customer service (good or bad), I'd love to hear about it.

From Paul Snyder, forum technical advisor:
Your test sounds a lot like the KCMA certification testing. In the testing, the application of the finish is just as critical as the finish itself. With most water-base finishes, the wet mils, number of coats, time between coats, and cure time have a big impact on the finishes' durability. It's just the nature of the product. And like any finish, dry film thickness, easing sharp corners, and sealing end grain play a big part in how well the finish will hold up in a kitchen or bath.

For water-based finishes, I usually use Target Coatings and I noticed they let the finish cure longer than you did before they do the testing. And they have specific wet mils recommendations as well as time between coats for optimum performance with minimal cure time. I'd guess that all the water-base manufacturers have similar guidelines.

From the original questioner:
Paul, I did this finish comparison to find out which finish performed the best for me in my small shop and my limited finish experience. I did my very best to treat all products equally and fairly: all products were put on maple, all edges were eased, both sides were finished.

Someone said 7 days was not a long enough time to let the finishes cure but this was per the manufacturers' specs. The test was done on only one side of the sample pieces of wood, so maybe I will try again in a couple of weeks.

I know you said you use Target coatings and I did not test their product, but there are so many to choose from. I wish I could test every finish there is, but that is not possible.

There might be a few people who think I am a sales rep for somebody, but I assure you I am not. I will restate that I chose SDA/Craft for my finish because of how their product performed and their proximity to me. But I would also like to say that Fuhr by far had the best customer service and all of the companies provided sample products to me at no cost or only shipping charges.

From Paul Snyder, forum technical advisor:
I didn't get the impression you were a sales rep and I don't see where anyone else would. The point I was trying to make is that each manufacturer will probably have exacting application guidelines to get the best testing performance from their finishes but other than waiting a week, you didn't say anything along those lines.

I think your test told you what you needed to know and helped you pick a finish that meets your needs. You found the finish that performs the best according to your application technique, re-coat schedule, and cure time. It's a lot more than most folks ever bother to do.

From contributor S:
I will say again - and I do not often repeat - that one week for a test is not long enough with regard to waterbase finishes. They need at least three to four weeks to fully cure themselves out.

The one week listed on a can… is that what you will rely on? A contributor on this forum made these observations about how long waterbornes need to cure before they are truly useful, and that was more than a year ago. It took a little, but one or two suppliers/formulators in that thread did admit that waterbornes need a while to fully cure. Fact, not opinion, and not container label hype.

Remember, it is manufacturers and suppliers who hype the solids ratios of their products by weight instead of by volume. Weight is a useful number for regulators and formulators. Only the volume measurement is useful for us finishers who need that info to complete the math on our dried mil thickness.

Just to make the playing field level for any waterborne, keep it at four weeks.

By the way, what about waterborne floor coatings? They say you can walk on them within one day in your socks. How long before you can expect normal traffic patterns for your newly finished floors? The manufacturers for those coatings do not shy away from the rule of a few weeks.

Four weeks for waterborne. And four weeks for solvent precat. And four weeks for conversion coatings. That's if you really want to do proper comparisons and tests from one product to another. It's just like gestation and kids, we don't start testing them in school until they are born. Until then, it's all hypothetical.

From contributor T:
In the real world, finish rarely gets to cure 4 weeks before being exposed to some water (rain during delivery, a sloppy tile setter or a careless homeowner). 1 week is very realistic and should at least represent part of any testing. Are we supposed to let cabinets sit in our shops for a full month prior to installation? For those of you that can afford that luxury, ignore the questioner's test, for the rest of us, it was very informative. I have yet to see anyone else put forth as much effort and share their findings as Toby, and I, for one, am thankful. Curing fastest to water/chemical resistance is a major selling point in my book and shouldn't be ignored.

From contributor G:
You need to check out the Crystalac waterborne finishes. Not waterbased, but of hydrophilic resins that permit water cleanup, safe, nontoxic when dry, very easy to apply with HVLP equipment. I have been using them for over a year and we have no complaints.

From contributor O:
I really appreciate that you shared your testing results with the rest of us. Our shop is moving to all waterbornes, despite the scowls of many other professionals in our industry. I don't know if you are considering a system to force cure the products, but we have researched IR and convection ovens as well as Optimum Air's ultra low humidity technology and have decided to install an IR oven.

We used MLC Ultrastar satin for several years and were able to get a beautiful finish initially. Upon returning to a kitchen some three years later, the finish was definitely failing. I can't guarantee that we followed the correct application procedures, so my criticism of that finish remains anecdotal and not scientific.

From contributor B:
Interesting. I've been using Enduro poly for a little over a year now and have been very satisfied (after a lengthy learning curve). I work as a cabinetmaker and mostly finisher. Most of my finishing background is with conversion varnish, so I think I know what a durable finish is and should be able to do.

One thing that I have a hard time with is the amount of finish applied in the tests described above. Three coats of any finish is hardly what I would consider a durable finish, especially if you're sanding between each application. I doubt you have hardly any finish left to protect your cabinets. I do three applications and sometimes four if I'm working with a soft wood like alder.

First step is two coats of sanding sealer (no sanding between coats), then scuff sand with 400 and clean up with synthetic steel wool (3m purple metal grade), next application, two coats of gloss (no sanding between coats), then sand and clean up as above. Final coat is a catalyzed (crosslinked) topcoat. It is very important to properly mix the catalyst into your mixture or you won't get the desired results.

Also, I couldn't agree more that the actual cure time is four weeks. One day per coat is the rule of thumb. But like most here have stated, that's just not the real world. All of my invoices clearly state full cure is four weeks and to avoid caustic cleaners in the interim, and that recommended clean up is soap and water, or some other mild cleaner (409, etc.).

From the original questioner:
Your success with Enduro may be due to use of the crosslinker. I don't want to use a crosslinker because I understand they have harmful fumes and AQMD issues like those associated with CVs.