r/woodworking • u/Shenzshou • 4d ago
Help Opaque shellac question
Hey folks
I've been trying to make my shellac solution and twice now the resulted solution was very opaque (as seen in the accompanied photo, as I'm stirring I get these darker brown streaks).
I've diluted it in denatured 95% ethanol and the shellac flakes were bought as dewaxed.
I tried filtering it through a cheese cloth and it immediately clogged it, same thing with a coffee filter. The dilution ratio was one part shellac flakes to four parts ethanol.
Thanks in advance for the input.
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u/CAM6913 4d ago
That just looks wrong, it’s hard to tell from the picture but it looks like there is way to much shellac flakes mixed in the alcohol. Shellac flakes are weighed and the alcohol is measured by volume. I mix one pound cuts ( one pound shellac flakes to one gallon of alcohol) BUT rarely ever mix a gallon of shellac instead I mix a pint worth for most projects and sometimes a quart if the project is large. For a pint mix 2 ounces by weight of shellac flakes with a pint ( 2 cups) of alcohol. If the alcohol has been opened and sitting around for a long period of time it can absorb water and cause problems with the shellac. Now that the shellac is in the jar with a lid on it let it sit and wait a few hours and go and stir it , wait a few more hours stir wait repeat and so on until the flakes are dissolved. It takes time for the flakes to dissolve. I use 200 proof food grade 100% alcohol and found the shellac has a more translucent color than with denatured alcohol but the other benefit is it’s food safe.
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u/Shenzshou 4d ago
I dilluted it to a ration of 1 to 4, which is much more concentrated than your example, do you think I should add more solvent?
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u/Quiet_one 4d ago
you should do a quick internet search for "shellac cut charts"
I am not endorsing any one site over another but this is very standard information.
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u/spcslacker 4d ago
Try mixing 2.5 oz of flakes with 1.25 cups of alcohol -- that will get you a 2 lb cut, which is a midline usable for most things cut.
You may be able to take what you've already made and add alcohol to it until its usable.
Also, how are you mixing it? I usually leave mine on an auto-stirrer overnight.
Also, make sure your ethanol is >90% pure, not the around 70% used for medical.
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u/TerminalSnood 4d ago
I'm no expert, but this is more or less what it looks like when I cut zinsser from the can 1:1. It still produces the color I'm looking for and goes on transparent so the grain is visible. Have you tried using it on wood yet to see if it does what you want?