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Dan Jansen
05-23-2018, 4:13 PM
I recently posted about spraying good old Minwax Polyurethane and got lots of great answers (Thanks!)

In the past I’ve always used MW Poly because it’s good stuff and I like the hard, waterproof finish. I’m looking at various options to replace it for finishing with my HVLP. I’m not close to any major stores save a Menards so I’m going to have to order online. My research tells me water based poly has some advantages like less mess and less nasty stuff in the air. It looks like General Finishes and Target Coatings are the two biggest brands available to hobbiests like myself. It looks like Target’s EM 8000 is designed to emulate my old favorite. GF has Enduro-Var but it’s seems to not like oil stains. So, are these my best options to replicate Polyurethane? Is there another brand? Or should I shellac then use a clear finish like was suggested in my previous post?

Jim Becker
05-23-2018, 5:16 PM
I have no experience with the General Finishes products, but many folks here do. Target Coatings is my own go-to for water borne finishes and I've used EM6000 (and it's predecessors), EM6500, EM2000 and EM8000cv. If you want the warmth of an oil based finish "out of the can", EM2000 is an emulsified alkyd that has a hint of amber warmth that you are used to with the oil based varnish you've been using. EM8000cv has a little warmth to it, too, and provides a very durable surface. Do note...non of these are "polyurethane" finishes. In Target's line, they do offer the EM9000 water borne polyurethane and the EM9300 Polycarbonate Urethane products if you feel you need the properties that polyurethane resins bring to a finish.

The reason that de-waxed shellac was mentioned previously would be to cover two scenarios. The first is to act as a barrier coat between, say, a colorant and/or oil and the top coat so that any incompatibilities don't affect adhesion of your top coat(s). The second reason is that it can add a little warmth to counter the typical "colder" clear color of most water borne finishes. I only use it for the former as I typically use BLO and/or water soluble dyes prior to applying my clear coats.

John TenEyck
05-23-2018, 6:41 PM
I use a lot of GF's products. None of them look much like OB poly w/o help. The simplest way to make them look like OB poly is to add some Transtint Honey Amber dye; doesn't take a lot either. And, IME, EnduroVar bonds just fine over OB stain as long as it has dried for at least 72 hours; alternatively, you can spray a coat of Sealcoat shellac to seal it and create a bond layer. That is my typical approach when using WB topcoats over OB stains.

Are you aware that MinWax makes a WB oil modified poly? I haven't used it but have heard from others that have that say it is a very good product. You should be able to buy it locally, too.

John

Dan Jansen
05-23-2018, 8:00 PM
Are you aware that MinWax makes a WB oil modified poly? I haven't used it but have heard from others that have that say it is a very good product. You should be able to buy it locally, too.

John

Do you mean Polycrylic? The stuff in the bluish green container? I’ve never brushed or sprayed it. Or is there something newer out?

John TenEyck
05-23-2018, 8:30 PM
No, not Polycrylic. This stuff: https://www.sherwin-williams.com/homeowners/products/minwax-waterbased-oilmodified-polyurethane You can buy it at SW's, Lowe's and other local places or order it online.


John

Patrick Chase
05-23-2018, 10:14 PM
Do you mean Polycrylic? The stuff in the bluish green container? I’ve never brushed or sprayed it. Or is there something newer out?

No, Polycrylic is an old-style acrylic water-based finish. It dries "clear", though I've put that in quotes because I find it a bit milky/plasticky. I frankly don't think it's a very competitive finish by today's standards.

Some more recent water-based finishes actually use oil-modified resins similar to the ones in an oil-based varnish, and then use polymers to suspend those in a water base. Examples in include General Enduro-Var and Target EM2000 (which John and Jim mentioned above, respectively). Minwax offers this (https://www.minwax.com/wood-products/clear-protective-finishes/interior/minwax-water-based-oilmodified-polyurethane), though I've no idea how it stacks up.

John TenEyck
05-24-2018, 10:47 AM
No, Polycrylic is an old-style acrylic water-based finish. It dries "clear", though I've put that in quotes because I find it a bit milky/plasticky. I frankly don't think it's a very competitive finish by today's standards.

Some more recent water-based finishes actually use oil-modified resins similar to the ones in an oil-based varnish, and then use polymers to suspend those in a water base. Examples in include General Enduro-Var and Target EM2000 (which John and Jim mentioned above, respectively). Minwax offers this (https://www.minwax.com/wood-products/clear-protective-finishes/interior/minwax-water-based-oilmodified-polyurethane), though I've no idea how it stacks up.

Patrick, unless GF changed the formula for EnduroVar I don't think it is an oil-modified WB finish as you mentioned above. Back when GF and others had to publish MSDS's I saved the one for EnduroVar. Here's what it says:

SECTION 2: Composition/Information on Ingredients
CAS # Chemical Name Percent TLV PEL
7732-18-5 Water 65-75% Not applicable Not applicable
108-01-0 2-dimethylaminoethanol 1% Not established Not established
57-55-6 1,2-Propanediol <1% Not established Not established
8440P Urethane Polymer 20-25% Not established Not established
872-50-4 N-Methyl-2-pyrrolidone <4.5% Not established Not established

John