How to reduce the gloss on Acrylic poly

[Larry Browning]

I found a deal on a gallon of General High Performance Polyurethane. However it is gloss sheen but I prefer semi-gloss or satin. Is there a way to reduce the sheen? Maybe an additive or something.

[Scott Holmes]

You can buff it with steelwool or a scotchbite pad to make it satin. If you want gsemi-gloss buff it after the steelwool os use a rubbing compound to knock the shine off.

Is it acrylic or poly? They are not the same thing. Waterborne is acrylic oil based will be poly. If you are using this on floors (which is the only place I use poly) you should be able to get a flattening agent from General Finishes. Or buy a qt of Satin and let it settle until you can por off the clear top and use that flattening agent to make a semi gloss.

[Larry Browning]

Is it acrylic or poly? They are not the same thing. Waterborne is acrylic oil based will be poly.
According to General's web site it is: High Performance Polyurethane Top Coat, which is an acrylic polyurethane.

High Performance Top Coat is the hardest, most durable consumer polyurethane top coat on the market today. It contains all the consumer friendly characteristics of PolyAcrylic Blend. In addition it contains a UV Stabilizer to protect it from breaking down in sunlight and to protect the underlying stains from fading. And with its pure polyurethane durability, it can even be used on floors. This is the most durable product. Available in the following sheens, Satin, Semi-Gloss and Gloss.

[Tony Bilello]

You can buy flattening agent. I dont know if they work on poly I havent bought any in quite a while. Mohawk Finishing Products has it I believe and I know Woodfinishersdepot.com has it.

[Scott Holmes]

It's a hybrid, 40-50% acrylic; 10-20% urethane, per the MSDS. Of course it's harder than poly all acrylics are harder than poly.

I see that the % of urethane is up from the 3-5% that used to be in the hybrids; chemistry is improving.

I still don't like the marketing folks saying "water-based" it's water-borne; thinned or dispersed with water.

Beer is water-based; MADE from water.

Varnish is oil-based; MADE from oil.

[Larry Browning]

I also bought a quart of the semi-gloss (at full price) because of my current project. Would it be acceptable to use the gloss for the 1st 2 coats and then apply the semi-gloss as the final coat? That way the semi-gloss would go further.

[Howard Acheson]

>>> Would it be acceptable to use the gloss for the 1st 2 coats and then apply the semi-gloss as the final coat?

The gloss of the final coat determines the final gloss.

[Glen Butler]

I also bought a quart of the semi-gloss (at full price) because of my current project. Would it be acceptable to use the gloss for the 1st 2 coats and then apply the semi-gloss as the final coat? That way the semi-gloss would go further.

Because the amount of solids in gloss and semi-gloss are different this could cause the semi gloss to crack. You can safely use gloss on top of semi-gloss, but there are risks involved doing it the other way around. Not a guarantee to crack, but a risk. Be sure to sand well. Maybe test first.

[Scott Holmes]

I have used gloss then Satin or semi-gloss over the gloss may times.

The only time I would expect cracking would be from a too thickly applied coat and/or improperly dried previous coats...

The solids content would not make much difference, since it would only be related to the amount of solids left after the thinner has evaporated.

[Larry Browning]

Well, I applied 2 coats of gloss and 1 coat of semi-gloss over the weekend and everything looks good. When would this cracking appear? As it dries, or over time? Because there is no cracking now. I think it looks pretty good.:)

[Glen Butler]

Well, I applied 2 coats of gloss and 1 coat of semi-gloss over the weekend and everything looks good. When would this cracking appear? As it dries, or over time? Because there is no cracking now. I think it looks pretty good.:)

Cracking would appear as it dried. Sounds like you are good to go.