So how are sheens measured?
There are as many names for sheens as there are for stain colors. Every manufacturer uses different names to describe what they think a particular sheen should look like. I'm sure you have heard many of them; flat, dead flat, satin, egg shell, matte, gloss, hi-gloss, and the list grows every year as companies try to differentiate their products. While there is a general understanding of what these names may mean, there is absolutely no guarantee that every product called satin will be the same sheen! If you are purchasing a new coating that you have no experience with, you don't have to make a sheen choice on name alone.

	To ensure consistent sheens from batch to batch, manufactures use gloss meters. Gloss meters measure the angles that a light beam bounces back from a dry coating sample. Thus providing us with a standardized gloss measurement that can be used between brands and different types of coatings!
	Flattening paste reduces the gloss by reflecting light at different angles. The more particles added to your finish from a flattening paste, the less light reflection you will have. The particles absorb the light and bounce it back at different angles. In a full gloss surface you can see your reflection, but in lower sheens you cannot. Flattening paste is the reason.
Typical Sheen Degrees by Name	5-10 degree angle is dead flat to flat 25-35 degree bounce is a satin 50-60 degree bounce is semi-gloss 80-90 degree bounce is full gloss

You can usually find the degree of sheens from the manufacture, or often it is located on the product data sheet (PDS). You know, the one with all the technical information about the product that most of us don't bother to read!

So if it is a standard that everybody can use, why doesn't everyone use it?
Good question! Wood Finishers Depot tries very hard to provide the degrees of sheen on most product labels. You will find it on most of our standard wood coatings and even on most of our clear aerosol sprays. Unfortunately everyone doesn't provide all of this information on the label, but it is almost always available if you ask for it!

Here are a few guidelines to keep in mind when using this product:

When using in a lacquer based product thin the flattening paste with lacquer thinner to make it easier to go into suspension. Remember that flattening paste is made from silica, a form of sand, so by reducing the paste with lacquer thinner you are also helping to disperse the silica grains into a liquid suspension.

Always use a mechanical stir paddle or paint shaker when using flattening paste. Flattening paste is often difficult to get into a liquid suspension. Manually stirring by hand will not provide the shear necessary to cut the solids into a liquid suspension. By first thinning the paste, and then adding while mechanical stirring or shaking on a machine afterwards you will have less problems with your flattening paste.

Always strain your coatings into your spray gun, this will catch any particulate or other trash left in the coating before it enters your spray gun. It is always a good idea to strain all of your coatings, but after adding flattening paste it is mandatory. Trust me when I say that little white speck of flattening paste will show up in the middle of your table top. Not on the legs or the table apron, but right in the middle of the top! As they say, been there, done that and I have the T-shirt!

You understand how flattening paste works, you know how to mix, now how much do I add?
While different types of products (varnishes, vs. lacquers, etc) all hold the flattening paste differently, the chart provided below is a simple guideline for lowering sheens in common finishing products. Keep in mind it's not precise, but just a general guideline to help you get started. As always follow the directions and do a spot test before spraying the entire piece.

Also keep in mind that the only difference between sheens of the same product are the flattening paste. Yes, manufactures use the same process described here, but in large batches, to produce different sheens. So, by inter-mixing different sheens of the same product, you can achieve the same results as by manually adding flattening pastes. If you start knowing the precise degree of sheen that each product has you can mix with predictable results.

Example: If I have a gallon of "off the shelf" gloss that measures 90 degree, and I mix it with another gallon of "off the shelf" dead flat that measures 10 degrees, the adjusted result will be a 50 degree sheen, what I consider to be a semi-gloss. The advantage is that I have manipulated the sheen with "off the shelf" finish, and without having to manually add any flattening paste.