Water bsed poly

[mlehikoinen]

So, in one of my previous projects, I used water based Poly - Actually, it was called Varathane. Trying to apply by wipe on is next to impossible as it gums up the rag like a well used hanky by the worst headcold recipient. What is up with that?

Being in Canada, the water poly market seems to be rather limited.

Any thoughts or recommendations? Is there a way to thin water based poly so that you can apply via wiping methods? I already know that using mineral spirits is NASTY . Don't ask what possessed me to try LOL

[thewoodwhisperer]

Hey Mike. Generally speaking, water-based topcoats will all look like 1% or 2% milk. That's just the nature of the beast. Now I know some folks have had success applying water-based finish with a wipe-on method, but I am not one of those people. I have never liked the results. You can even dilute 10-15% with water, and it doesn't really help much. So maybe someone who has has luck with this method can chime in and give us their secrets. Keep in mind you do always have the option of using a brush instead of a rag. That should be a little easier to work with.

For me, I find spraying to be the most satisfying and effective way to apply a water-based finish.

[PaulMarcel]

Just a reminder to use a synthetic brush if you are going the brush route.

[mlehikoinen]

Thanks Marc and Paul-Marcel. I'll keep those in mind. The only reason I was using the water poly was for the insides of drawers. I didn't want my daughter's clothing stinking to high heaven.

Not quite up to buying an HVLP system yet, but considering it! Maybe next year when I plan on getting an air compressor.

[PaulMarcel]

Any reason you want to finish the inside of the drawers? Shellac will keep any stink out... it's the "Ancient Chinese Secret" (well, Indian...) in paints and primers that odor block. And since it always comes up with kid stuff, shellac is completely kid safe... in fact M&M's are finished with Shellac.

This brings up a great point... if your kids are eating way too many M&Ms and not leaving the greens ones for you and the lady of the house, explain to the children that M&Ms are coated in shellac and that shellac comes from the dead dried bodies of bugs crushed and dissolved in alcohol.

[Ben H]

Any reason you want to finish the inside of the drawers? Shellac will keep any stink out... it's the "Ancient Chinese Secret" (well, Indian...) in paints and primers that odor block. And since it always comes up with kid stuff, shellac is completely kid safe... in fact M&M's are finished with Shellac.

This brings up a great point... if your kids are eating way too many M&Ms and not leaving the greens ones for you and the lady of the house, explain to the children that M&Ms are coated in shellac and that shellac comes from the dead dried bodies of bugs crushed and dissolved in alcohol.

I thought it was the puke of the female lac bug? Mmmmm.....tasty!

[LordLQQK]

I thought it was the puke of the female lac bug? Mmmmm.....tasty!

Yep yep yep.....HURL.

LQQK

[PurpLev]

+1 for shellac for inside of drawers.

on a side note - mineral spirits is meant to be used with oil finishes, not waterbases. for waterbased finishes only use water.

[schafersound]

Mike,

Ran into the exact situation with Varathane, in Canada. Is it Varathane or the in Canada part that is giving us the trouble? Also one of my pet peave stories about lousy customer service in Canada, so a little rant here that leads to my solution to the problem. The first coat I applied with a synthetic brush (as suggested by other posters) and ended up with a very rough finish. Sanded and put on the second coat, same result. I went back to the dealer with the problem (Windsor Plywood, for the US guys, well respected hardwood supplier here) and was told by staff I should use a natural fibre brush, $8, same result. Back to the store, different clerk, "oh, no, you should use a synthetic brush, but why don't you save yourself some money and just wipe it on?" Well, I tried that and I had the same problem you were having Mike, the cloth immediately gummed up and got sticky, I couldn' overlap the wipe, etc, sound familiar?

What I found is it goes tacky on the surface really, really fast, almost instantly (I don't think thinning will change this) and that's probably why it works well as a spray on finish. So, brush, cloth, doesn't matter, touch it a second time and you stick, pulling up the surface. I had to make this work because spraying isn't an option in an apartment. The solution was to use a staining pad, get it sopping wet and flood the surface in one pass, then do the adjacent edges (if any) to catch the runs and coat the edge and DO NOT TOUCH AGAIN! and I got a perfect finish. Where I did have to overlap, the flooding effect created a liquid barrier between the surface and the pad so no stick. If you have some leftovers give it a try on some scrap, it was really cool when I finally found the solution because I like the hard finish Varathane gives for high wear surfaces, holds up really well. Oh, yah, put down plastic, this is really, really messy, but fun!

Still making sawdust on

The Great Left Coast

Garth

[rob45]

Hello Mike,

First post on this forum, so hello to all.

My background is finishing, and I could not help but notice your question.

Working with the water-based polys does present some challenges. Not so much that it is difficult, but that it is different.

Yes, it gives a "milky" appearance when wet, but dries to a clear finish. You may dilute with water, but I usually find that unnecessary unless you need to thin it enough to push through the HVLP. One advantage to the milky appearance is that it allows one to gauge the "evenness" of the application if they're not familiar with the process.

If not employing a spray application, best results are usually obtained with a synthetic brush. A natural brush does not work well for this.

Using a rag or sponge generally creates more work; here are a few reasons:

1. No matter how "lint-free" the rag is supposed to be, it will probably still leave lint fibers in your finish. This is especially true if your surface is not ultra-smooth.

2. Use of a sponge is not exactly ideal, either. Tiny pieces of sponge material in your finish is just as bad as lint. As you run the sponge over the surface, it tends to "catch" on the surface. Look at the surface of a "worn-out" sponge- that stuff had to go somewhere. Just like with the rag, the smoother the initial surface, the less of a problem this will be.

3. Any time you use a rag or sponge, your own hand is what determines the evenness of the coat. Gauging pressure with your hand is far more difficult than letting the bristles of a brush do the work for you.

4. Use of a cloth or sponge allows less working time- both of these will soak up enough that less product is going onto the surface. So you actually have a thinner coat on the surface than intended; if you need to overlap or fix a mistake, the product is already setting up and you have the already familiar gummy mess. The brush keeps the product fluid for a longer period of time, in addition to allowing a more even coat.

Garth's post caught my attention.

He mentioned the "very rough finish". For those not familiar with use of water-based polys, the initial coat will nearly always be rougher than when using an oil-based product.

We all know what happens when water comes in contact with wood- the grain raises and becomes rougher. But another thing to consider is the fact that the poly is actually working its way into the pores of the wood itself. As it dries, the wood grain is sealed.

So what happened to all the sawdust/dirt that was in the pores of the wood to begin with? No matter how well you vacuum the surface before coating, that stuff is in there. The water-based poly aggravates the problem by "floating the dirt" to the top. This problem is less aggravated when using an oil-based poly.

This is less of a problem when one is using a dense, tightly-grained wood. A good side-by-side comparison would be coating red oak vs. maple- no matter how smooth you sand the wood and clean before coating, the initial coat on the oak is going to be rougher. LIGHTLY sand, clean, and apply another coat, and the differences become less apparent.

Garth did mention his solution of flooding the surface to prevent the quick setup. That is indeed a viable solution; it really depends upon your particular situation. Obviously it works best with a flat, level, and horizontal surface. More product is used than necessary, and drying times are considerably longer. Drying time is important because very few of us work in a completely dust-free atmosphere; the longer it stays wet, the more time you allow for airborne dust/debris (or in my case, BUGS) to settle into your finish.

Every situation is different, and I do not know all of the details of yours. Were I in your shoes, I would try these steps.

1. Start with a smooth, clean surface.

2. If not spraying, I recommend a quality synthetic brush. If you feel better trying a cloth or sponge, that's OK, too. Due to reasons stated above, a brush will tend to be more forgiving, possibly enabling you to produce better results.

3. Multiple light coats (with light sand and clean between each) are usually best with this type of product.

4. Keep the poly well-stirred. I stir every time I dip the brush.

Best of luck,

Rob