...That is, indeed, the question. 

When I put the de-enameling section in my book “Enameling on Metal Clay”, I thought it was understood that de-enameling is a course of last resort; something to do when the alternative is tossing the piece in the recycle bin.  I’m now discovering people are using it if they are only slightly less than satisfied with their results.  Here’s the thing about de-enameling… It’s not a cost-free eraser.  It’s not like you can keep applying enamel and taking it off indefinitely until it’s perfect.  There can be side effects which get magnified with each repetition of the process.

Before making the decision to de-enamel a piece you need to ask yourself some questions.  Did the enamel come out really badly?  Is it pitted, burnt, or bubbled?  Or is it just that you didn’t get exactly what you were expecting?  Maybe the color is a bit off, or it doesn’t look quite like you envisioned it?  If the answer is in the latter category, my advice is “Learn to love what you got”.  Enameling is a constant source of surprises and “design opportunities”.  Embrace the unexpected!  Remember, others looking at your work won’t know what was in your head when you made it and will judge it differently than you will.  We often focus on “what we didn’t get” and lose sight of some of the beautiful things we DID get because of that. 

If the piece is truly destine for the rubbish heap, so nothing of value will be lost by attempting to de-enamel it, there are a few things you need to be aware of before attempting to RE-enamel it.  After de-enameling the surface of the silver may become coarse and pitted.  Also, attempts to re-enamel may result in the enamel pulling or failing to adhere to the silver.  The metal will need some treatment before proceeding.  I will address that later in this article.

Instructions for de-enameling:

Tools and supplies
Table Salt
Cream of Tartar
Water
Kiln
Firing rack
Mica sheet
Brush
Wire Brush 

1. Mix equal parts table salt and Cream of Tartar.  Add just enough water to make a thick paste.  
2. Apply the paste to the enamel, coating it very thickly. 
3. Put the piece on an old piece of sheet mica (you won’t be reusing this mica for enameling. Keep it aside for de-enameling only) and place it in the kiln at 1450F (788C)  for 2 minutes.  The mixture will burn, smoke and blacken. 
4. Pull it out of the kiln and while it’s still glowing hot, drop it into a bucket of cold water.  Most of the enamel and crusty black stuff should break off. Some of it may need to be chipped off with a metal tool.
5. Use a wire brush to remove the remaining de-enameling residue.

After de-enameling examine the piece carefully.  If the enamel was very thick, or the piece very detailed, it may be necessary to repeat the de-enameling steps to remove every trace.    After all the enamel has been removed, re-fire the piece at 1600F (871C) for 10 minutes.  There should be no blackened areas.  The metal should be clean and bright.   At this point tumble the piece for a minimum of 2 hours.  If there are flat, untextured areas to be enameled, you may want to get in to those with a hand burnisher also.   Clean the piece well with a glass brush and ammonia.    At this point the piece should be ready for re-enameling.  

In some rare instances, after de-enameling the re-applied enamel will continue to pull and fail to adhere to the metal.   The refiring and tumbling should have taken care of that, but if it doesn’t, I recommend using a technique other than enameling to finish the piece.   Epoxy resins, colored pencil and patinas can all be used to add color and interest to a metal clay piece.