Residents of countries/states that level restrictions on the quantity of VOCs (volatile organic compounds) in their finishes might be left in two minds as to whether adding compatible solvents is actually against manufacturer's recommendations or simply a symptom of local VOC regulation.
....you can’t do any harm to any finish by adding thinner. In fact, you can add all the thinner you want to solvent finishes, even 99 percent, without causing any harm. You’ll just get a thinner build with each coat, which may result in your having to apply more coats to get the look and protection against liquids that you want.
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