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Dewaxing shellac
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=38369		 Page 1 of 1
Author:  aqualibguitars [ Tue Nov 27, 2012 4:36 pm ]
Post subject:  Dewaxing shellac
Hello friends
i get shellac flakes with wax in my locality.
can we dewax the shellac in our workshop?
is there any procedure?

also our laws dont allow 100% pure alcohol
it is mixed with water about 40-50 %
can we use this alcohol to dissolve the shellac and
go ahead for french polishing?
Author:  Ron Belanger [ Tue Nov 27, 2012 4:50 pm ]
Post subject:  Re: Dewaxing shellac
Alcohol for shellac should be 95% alcohol. Anything less and the shellac will not dissolve properly. If you can't get ethyl alcohol, then you should be able to get denatured alcohol.
As far as dewaxing is concerned, after the shellac is fully dissolved, let it sit for a few days and you will see a sediment form on the bottom. Decant the shellac off this layer and you will have dewaxed shellac.
Author:  Michael.N. [ Tue Nov 27, 2012 6:15 pm ]
Post subject:  Re: Dewaxing shellac
Sometimes it takes a lot longer than 3 days though. I prefer the tea bag method.
Author:  CharlieT [ Tue Nov 27, 2012 6:26 pm ]
Post subject:  Re: Dewaxing shellac
Michael.N. wrote:
Sometimes it takes a lot longer than 3 days though. I prefer the tea bag method.

Can your please elaborate on that? That's a new one to me.
Author:  WaddyThomson [ Tue Nov 27, 2012 6:43 pm ]
Post subject:  Re: Dewaxing shellac
put the shellac in a cloth sack, or t-shirt material wrapped around it and tied at the top with a string. Hang it in the alcohol at the top of the liquid, but fully submerged. Let the shellac dissolve through the shirt material. This way, the heavier dissolved shellac works to the bottom of the jar and the clear alcohol rises to mix with the rest of the shellac. The wax and any impurities stay in the bag.
Author:  CharlieT [ Tue Nov 27, 2012 7:04 pm ]
Post subject:  Re: Dewaxing shellac
Thank you, Waddy. That's good to know.
Author:  RNRoberts [ Tue Nov 27, 2012 7:54 pm ]
Post subject:  Re: Dewaxing shellac
I dissolve flakes in Everclear (95% ethanol) similar to Waddy only instead of T-shirt material I just dump the flakes into the foot cut off of a pair of my wife's panty hose and suspend it in a jar of the alcohol. (I always use my wife's, as mine are much too nice to use for this, and someone else's wife's would create more problems than it's worth.) You do need to run the resulting shellac through a paper coffee filter to eliminate the wax, but I also did that when I used cloth for the "teabag".
Author:  CharlieT [ Tue Nov 27, 2012 8:21 pm ]
Post subject:  Re: Dewaxing shellac
Is there any advantage to buying "natural" shellac and dewaxing it yourself versus just buying dewaxed shellac? My only experience is with the dewaxed stuff.
Author:  WaddyThomson [ Tue Nov 27, 2012 11:16 pm ]
Post subject:  Re: Dewaxing shellac
It might be less susceptible to oxidation, which would make it last longer,
Author:  Michael.N. [ Wed Nov 28, 2012 7:39 am ]
Post subject:  Re: Dewaxing shellac
I think it's a lot less susceptible to oxidation. I've had waxy Button shellac sitting in a drawer for near 15 years and it still dissolves easily. I had some seedlac given to me that is 25 years old and it works perfectly well.
The beauty of the tea bag method is that you can place the whole lot in a jar and forget about it for a day or so. It looks after itself. If I want a strongly coloured finish I'll place the shellac, dye twigs, madder etc all into the tea bag and come back to it a few days later. Suspend it and let it drain for an hour or so.
Author:  Joe Sallis [ Wed Nov 28, 2012 8:15 am ]
Post subject:  Re: Dewaxing shellac
Quote:
I'll place the shellac, dye twigs, madder etc all into the tea bag and come back to it a few days later

this sounds like an interesting process, something I want to experiment with. What is a dye stick? Could you share any "recipes" with us? What substances can you put into the shellac?
Author:  Michael.N. [ Wed Nov 28, 2012 8:53 am ]
Post subject:  Re: Dewaxing shellac
I really mean 'dye woods' - they just look a little like twigs. These are the natural dyes. I've tried madder powder, Alkanet, Brazilwood and Sandalwood - all in with garnet Shellac:

12g Garnet Shellac
5g Pale Shellac
4g Sandalwood chips
2g Brazilwood chips
3g Alkanet root
2g Madder Powder

That's the proportions that I used. Seems to work, although it was just a complete guess on my behalf. Just experiment. There are other dyes and of course you don't have to incorporate as many as I have. It's cooking. Always do test pieces by leaving half of a sample in a window for a few months, leave the other half in a drawer without light.

In application you just have to be careful that you aren't building the colour too fast, otherwise it can all get very patchy. I'm brushing the stuff on.
More modern Aniline dyes are less fugitive but tend to be very strong colours. Again you may have to mix them to achieve the desired colour.

Image


The result, although in reality it looks darker and a touch more reddish than it displays on my computer screen:

Image
Author:  aqualibguitars [ Wed Nov 28, 2012 2:02 pm ]
Post subject:  Re: Dewaxing shellac
Friends
thanks for the help
really the topic was so interesting so it catched all of ur attention
from now i will do the teabag method and let u know the results
till then
can u tell me the ratio of shellac to alcohol?
how many grams of shellac to how much ml of alcohol?
Author:  Joe Sallis [ Thu Nov 29, 2012 4:41 am ]
Post subject:  Re: Dewaxing shellac
Michael, good to see that the masters WILL share their recipes. It's a very intersting subject. i've started doing a web search and can see there are many natural substances that colour shellac. I'm going to experiment. Thanks.
Author:  aqualibguitars [ Thu Nov 29, 2012 8:23 am ]
Post subject:  Re: Dewaxing shellac
problem is that we have here alcohol with 50 by volume
and in denatured alcohol some amount of seedlac is added.
Author:  Bryan Bear [ Thu Nov 29, 2012 11:09 am ]
Post subject:  Re: Dewaxing shellac
aqualibguitars wrote:
problem is that we have here alcohol with 50 by volume
and in denatured alcohol some amount of seedlac is added.


How strong is the denatured stuff you can get. I wouldn't worry about a small ammount of seedlac in my alcholol if I was mixing shellac. . . :D
Author:  CharlieT [ Thu Nov 29, 2012 5:49 pm ]
Post subject:  Re: Dewaxing shellac
I may have missed something - apologies if I did, but is there an advantage to using the natural wood / plant materials to tint shellac rather than the commonly used dyes like Trans Tints?
Author:  nyazzip [ Thu Nov 29, 2012 6:24 pm ]
Post subject:  Re: Dewaxing shellac
Quote:
I really mean 'dye woods' - they just look a little like twigs. These are the natural dyes. I've tried madder powder, Alkanet, Brazilwood and Sandalwood

you wanna hear something amusing, i tried adding paprika powder to my shellac to get it a deeper reddish orange color....it actually worked(a bit), but i ended up with little red sprinkles in the finish, from the bigger chunks i guess. i should have let it sit awhile and strained it. worth another shot
so now my cello has some paprika flavoring sprinkled on a repaired area...tasty!
:D
Author:  Michael.N. [ Thu Nov 29, 2012 6:46 pm ]
Post subject:  Re: Dewaxing shellac
CharlieT wrote:
I may have missed something - apologies if I did, but is there an advantage to using the natural wood / plant materials to tint shellac rather than the commonly used dyes like Trans Tints?


No real advantage. Use whatever gets the job done, providing you like the colour. The Aniline dyes that I have are on the strong, vibrant side, therefore I find it easier to obtain a subtle colour with the natural dyes. I'm sure folk who dye cloth will tell you that you can't replicate the colour of natural dyes by using modern alternatives. Then again this isn't cloth. The advantage with aniline dyes is that they aren't as opaque as some of the natural dyes.

Paprika? Worth a shot. Tea and Turmeric have been used.
Author:  CharlieT [ Thu Nov 29, 2012 7:34 pm ]
Post subject:  Re: Dewaxing shellac
Makes sense. Thanks Michael.

Beautiful guitar, by the way.
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