Thread: Wood stain over Shellac?

Can't really stain over shellac, however applying more coats of shellac will will darken it more and more into honey colours.

You could add a little colour to the shellac using universal tint* but this will tend to blanket the grain a little.

You could strip off the shellac that's already on it and stain the timber.

*Universal tint - The stuff in the carousel at the paint shop they colour paint with. Ask if they'll give you a spot of yellow and red or if they have it orange. Then add a little (less than 20%) to the shellac and mix it in..

Originally Posted by ubeaut

Can't really stain over shellac, however applying more coats of shellac will will darken it more and more into honey colours.

You could add a little colour to the shellac using universal tint* but this will tend to blanket the grain a little.

You could strip off the shellac that's already on it and stain the timber.

*Universal tint - The stuff in the carousel at the paint shop they colour paint with. Ask if they'll give you a spot of yellow and red or if they have it orange. Then add a little (less than 20%) to the shellac and mix it in..

Thanks for the info. I guess I have to do some sanding before staining the timber. I'm looking at ColorTone Concentrated Liquid Stain from Stewmac. is this stuff good? They say it can be mixed with shellac to colour the timber.

No specific answers to your question, but if I were you I'd try to get a scrap of maple and experiment with your finish on that first. Write down what steps you take, and when you get the finish you want, then do it for real.

Peter

I can't say I have tried to stain over wood sealed with shellac, however I have used shelac to shield areas I don't want to stain whilst applying stain to other areas and it works well at preventing stain from penetrating the timber, so I would definately sand it first to ensure a consistent staining tone.

Cheers,

Peter

Originally Posted by peterbrown

I can't say I have tried to stain over wood sealed with shellac, however I have used shelac to shield areas I don't want to stain whilst applying stain to other areas and it works well at preventing stain from penetrating the timber, so I would definately sand it first to ensure a consistent staining tone.

Cheers,

Peter

Thanks for the tip.
I guess I would have to experiment and see what comes out best.

OK as one tries things as much to "do it" as well as to figure out ways to "get out of it" when the occasional disaster impends.....

I don't know a name for this process, but I will invent one;

"Reductive Dissolution".

It works.

Shellac - aside from strong acids, alkali's and long soakings in water, is relatively immune to almost all solvents EXCEPT alcohol.....

I have had to UNPATCH decals from my amplifers when the issue goes sidewards from air bubbles under them etc.,,

I did this by making a wad of cloth or toilet paper, soaking it in metho, and then applying that over the patch area, with a layer of aluminium foil over the patch and then some, and to use something to seal the foil over the area to slow the evaporation of alcohol right down... giving about 1 day or so of soaking time of the dried shellac, under the foil patch.

That is the removal of about 6 layers of THICKLY brushed shellac on an amplifier case... to get the defectively applied dacal off.

OK my solution.

Strip the guitar completely.

Remove the neck, wiring, switches etc... everything.

Take said guitar body and place it in one of those plastic storage boxes with their clip on lids.... the box has to be wide and long enough to lay the guitar body flat on the bottom of the box. Try to get as small box as possible to do this with tho....

OK now to the REDUCTIVE DISSOLUTION.

Buy about 4 or 8 liters of alcohol...

Put guitar body in box, fill box with enough alcohol to submerge the guitar to at least 1/2 way up the sides..... and then secure lid and place somewhere ventilated and cool.

Leave soak for 24 to 36 hours, and then inspect periodically.

When the shellac has dissolved off the guitar body, then flip it over and soak the shellac off the other side.....

When both sides of the guitar are shellac free, repeat the process several times on each side with fresh alcohol - to reduce the residual traces of shellac from within the timber surfaces.

I picked this up as a result of trying to measure out 0.2ml amounts of phenol, that the reduction process can be done like this; say the guitar has 100 grams of shellac on it, that redissolved into 4 liters of alcohol makes for a 1 in 40 solution (or 100gm / 4000ml)

When the guitar is resoaked into clean alcohol, there would be around 2.5 grams of shellac left in the surface of the timber - again a reductive dissolution of 2.5 grams of shellac into 4 liters of alcohol makes for a 2.5g/4000ml solution.

That is a reduction in shellac from 100 grams to 2.5 grams in one step, the second step takes that down to 1 in 1600 or 0.0625 grams of shellac left in the surface of the guitar timber.....

When it's repeated for the third time, the reduction is 1 part shellac to 64,000 parts alcohol.... or 0.0015625 grams of shellac left in the surface of the timber....

(I am quite tired at this point so my mathamatical faculties are fading fast...)

This is about as close to 0% shellac as your ever going to get, and it means that yoru guitar will be "perfectly clean" and ready for staining - without having to sand back unto the timber, UNDER the layer of shellac.

ALSO note that metho is denatured ethyle alcohol and there MAY be some components of the solution that could interfere with any inlaid plastic trimmings etc., on the guitar body... quick wipe over with metho is ONE issue, a soaking for 4 or 5 days in it, is another.

But what the hell.... this is where you start to learn all about inlays isn't it


Because I am a tight #### and alcohol costs, I'd probably distill the alcohol out of the mix and just reuse it....

Take one pressure cooker, LOW heat on an electric stove, great length of hose to disperse heat of alcohol vapor.... empty metho bottle.... in well ventilated area with forced ventilation....

The pressure cooker should give a fairly consistent "out gassing" without a lot of pressure behind it....

Ethyl Alcohol boils off at ~83*C..... and the vapor in sufficient concentration is a fire and explosion hazard.


And don't lean over the pot on the stove sniffing the fumes...