A variety of ways to remove the kiln wash are:
Grind the kiln wash off with diamond hand pads, or small rotary tool with wet sandpaper. You can then proceed to continue to grind with successively fine grits until a polish is achieved, or you can fire polish after a thorough cleaning.
|Example of scrubbing kiln wash off|
You can sandblast off the kiln wash and then proceed in either of the fashions above.
You can soak small pieces in vinegar and then scrub with a wire brush – a brass wire brush is preferable to steel one to avoid scratching the glass.
Another solution is to place small items in an ultrasonic cleaner basket with water and a little soap or proprietary cleaner. Leave for an hour or two and they should be free of the kiln wash.