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+-- Thread: Shellac Thickness (/showthread.php?tid=7058473)
Shellac Thickness - Willyou - 07-19-2015
I would be surprised if this hasn't been answered, but haven't found one.
Is it possible to apply so many coats of shellac that it causes problems of some sort with the finish; such as, cracking, crazing, chipping, poor drying, etc. I assume it's true. If so, what is the limit?
Re: Shellac Thickness - Scoony - 07-19-2015
Yup, you can get some alligator skin effect. You want shellac thin. If your using amber or garnet shellac and get the coat too thick, it can be problematic to thin it down as you will get color variations that are hard to fix.
Hard to get too thick by padding, but not so hard when spraying or brushing.
Re: Shellac Thickness - Willyou - 07-19-2015
I'm doing some test samples with 1# cut garnet trying to get the garnet color as deep as possible. I've applied 7 coats and have the color about right. Is that any where near to being too thick? If so, I'll have to start with some stain or dye before applying the shellac. That will make the process more complex and time consuming. My reasoning says that using a 2# cut won't help as I would likely end up with the same total thickness when I get the color I want.
Re: Shellac Thickness - Scoony - 07-19-2015
You can add dyes to the shellac to get a darker tone.
Re: Shellac Thickness - Willyou - 07-19-2015
Thanks. I had not thought of that. However, garnet is already pretty dark and I don't want to change the color, just deepen it so that I can use fewer coats. Also, is the thickness of 7 coats a serious enough problem to warrant the additional steps? Do you know which color/brand of dye to use and how much? Or, do I need more experimentation?
Re: Shellac Thickness - JR1 - 07-20-2015
Yes i is possible to get too many coats but usually by using to heavy a cut. More than a 1# cut (8:1 shellac to alcohol) is seldom useful. You should either use a different color Shellac like Ruby for more red or add TransTint dye to get the color that you want. TransTint in shellac is far easier to use than alternates as its easy to add or remove the colored shellac. I find that after ~5 1# cut coats you have reached the limit.
Re: Shellac Thickness - Willyou - 07-20-2015
JR1, Thanks for the information. I have no experience with Transtint. I can't help but wonder if the dye will be able to further darken an already very dark garnet color. In trying to find a place to start, I'm thinking that the black dye might have a better chance of deepening the color without actually changing it. Any experience with this?
Re: Shellac Thickness - jteneyck - 07-20-2015
I can't tell you which color Transtint to add to your shellac, but I can say that it is a better option than applying 5 coats of shellac as you will be able to get the deep color you want in only 2 or 3 coats.
You might have to add two colors of Transtint to get what you want. Look at the Transtint color chart for which colors to use. The beauty of Transtint is you can adjust the color from one coat to the next, if needed.
And, as always, test on scrap before putting any on your project.
John
Re: Shellac Thickness - David G - 07-20-2015
Yes, it is possible to apply so many shellac coats that the finish crazes later. DAMHIKT.
Re: Shellac Thickness - Willyou - 07-20-2015
Thanks for all the info and suggestions. I'll order some Transtint and do some more test samples.