# Water-based polyurethane vs water based polycrylic



## Jofa

I've been using oil based polyurethane for a few years, simply because I started with it and never looked back. However, it definitely adds a little tint to light wood.

I saw Minwax water-based polyurethane and polycrylic. I know that the polycrylic really doesn't change the color of the wood (this is what I've read). Question is, would this finish behave in a similar way to what I've been using? Mostly concerned with the ability to sand between coats in order to get some depth.

Thanks.


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## CharlieM1958

The polycrylic acts much like oil-based polyurethane as far as sanding between coats to build a finish. I've never used the oil-modified water-based polyurethan, so I'm not sure about that one.


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## SuperCubber

I love water-based poly, but with too many coats it can start to look "plasticy."


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## Craftsman70

I too have always used oil based. I'd read some things lately that said I should give water based poly a try so I gave Polycrylic a try a few weeks ago. I was disappointed. It seemed to go on very thin (as if it would need 2-3 times the same number of coats of poly), and it didn't seem nearly as tough as oil base.
That said, I saw the oil-modified polyurethane later and decided that maybe there is difference between real water based polyurethane and Polycrylic. I noticed the Minwax can of Polycrylic never said the word polyurethane anywhere on it.


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## LeeBarker

My instruments get WB poly. I can turn them in 2 hours (another coat). I stop at 6 - 7 coats. Up to that point they don't look like much, but quite suddenly the finish has the right (semigloss) depth for my eye.

If you are considering switching, Craftsman70, give it several wholehearted tries.

1. Strain your material for every coat.

2. Use a quality purpose-built brush.

3. Do not overbrush.

4. Sand only when you need to. I start with 320 and am at 500 or 600 at the end.

5. Let it sit at least a week before rubbing it out.

My understanding-and I wish I could find the verification for this-is that WB takes longer to fully cure but in the end it is tougher than OB.

Kindly,

Lee


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## wapakfred

There are better waterborne finishes than Polycrylic, consider any of the GF products, or maybe something from Target Coatings. That said, all waterbornes are basically an acrylic finish….those that declare themselves "polyurethane" simply add a small amount of urethane resins so they can paste that magic word on the label, we woodworkers seem to have some to believe that it's the end-all for finishing. Anyway, some of the early waterbornes actually had a very slight bluish cast to them, the later ones all seem to be more of the water clear. As for durability, the waterbornes are quite good. But a little over a year ago, Flexner wrote that in most cases the oil based finishes are still slightly more durable. That said, I think the waterbornes sand better than a oil based polyurethane, and they can be given a lot of depth. But it dos var a little between brands. Give them a try, but don't think that Polycrylic is the only one out there. One difference between the waterbornes and the oil base though, with oil base I never worry about how much I thin them; up to 50% if I want a wiping varnish. But with waterbornes you may upset the chemistry if you thin too much, with them it's best to follow manufacturer's directions for maximum thinning. My 2¢.


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## Jofa

Thanks for the great advice, guys.

I bought a quart of Polycrylic and a small, Husky detail sprayer. Tried it out today on a beer caddy and I really like the results so far.

One great thing is the lack of fumes. It also really sprays very well, much like water. I have a coat on there now and when I get back from work I'll shoot it a couple of more times.

Related question…

The sprayer I got is a siphon feed. I cleaned it out with water and went through a couple of canisters spraying water through until it was completely clear. Used my air nozzle to blow out any residual water (took it apart).

I've read that running some solvent through it will keep it from rusting the internal parts. Any truth to that and if so, what would you suggest? Thanks again.


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