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What is the main difference (from a woodworking point of view) between say a water based and oil based polyurethane. The idea of working with an easy to clean up medium appeals to me, but are there advantages to using oil based?

Ready to be enlightened .....

Dick

I finished a bedroom furniture build earlier this year. I used General Finishes water based stain and water based poly (GF High Performance Poly). I hated the stain and will never use a water based stain again. Way too difficult to apply evenly (as compared to oil). I liked the w/b poly mainly because of the ease of cleanup since I sprayed it. As for advantages of oil vs. water, I can't really say. I will say that the w/b poly dries quicker and seems to have the same end result as the oil based.

I see oil-based products, as well as shellacs, really having an advantage on dark woods as well as exposed end-grains. They sink in and look great. On the other hand, water-based poly can look 'whitish' in some of those end-grain situations.

This being said, I've had some projects where I've used an oil or shellac first coat, and then did the following coats with water-based poly, getting the best of both worlds.

OK, methinks that there is no simple answer here. I bought some WB from Minwax (I know, but I am not good enough yet for anything better yet) WB polyurethane as I have been using oil based until now. I did some T&G wall covering panels 25 years ago in my office and had half a gallon left over so I was using it.

Minwax says on the label that it can be applied over oil based stains so I will try it.

Thanks for the help guys. I hope the WB work as well as the OB, it will sure make it easier to use and clean up.

Dick

I struggle with finishing but lately I've been getting nice results, stress free, using Waterlox. It's been around a long time and is worth looking into.

Water based products always seem to disappoint me. They lack the long term durability of the oil based products. If you use oil based urethane, you can expect your finish to last longer than you do. With water based products, don't be surprised if you end up re-doing it again sometime in the future.
Water based urethane is still a far better product than shellac for durability, but it isn't up to the durability of oil based products.

rjent wrote:What is the main difference (from a woodworking point of view) between say a water based and oil based polyurethane. The idea of working with an easy to clean up medium appeals to me, but are there advantages to using oil based?

Ready to be enlightened .....

Dick

Here's a link that has a couple of links. Lots of info on just about any type of finish on the Flexner site.

beeg wrote:Water based or oil based? DON'T mix the two. Oil stain with oil top coat.

Oil and water don't mix, that's why lithography works, but I follow oil based stains with water based top coats frequently without any issues. In this thread https://forum.shopsmith.com/viewtopic.php?t=15305
I detail the finishing schedule where I've done just that.

Let me point out that it is imperative that the stain(s) have completely sunk-in/dried/flashed-off before top coats are applied.

Okay you all had your says and experiences. I am back and a finish guro. Water based stains on large medium to large areas dry faster then the wipe off time, they are a latex product. 2nd no matter what you use, a coat or 2 of 1-2lb cut shellac seals it for a next coat no matter what base it is.
Water based Poly dries the clearest of any finish, it adds no "yellowing" to it, the natural time of patina, fine for some things like over "milk paint" to keeps its true color.
You use a dye to get the color you want, then a coat of thin shellac or a cut oil based poly, then a buff with maroon pad. or 320 grit lightly, then an oil based stain of the same color you want, to fill the pores of the wood, the pigment in the stain goes into the pores that were not filled with the shellac or the poly, and now you have the color and the stain pigment gives it depth!!!