GLAZE-BASE (k) Repairing
To repair glaze-base, keep some of the each one you use in pot with a lid, as this helps to keep it clean and in a liquid state. Have them in pots of different sizes, shapes or colors, or mark them so they can be quickly recognized, different colored electric insulating tape is good for this. Mix them well before using and if they start getting dirty, change them as dirty glaze-base will be seen to be a shade darker after firing.
While cleaning the glaze-base off tiles, you might find that some are damaged. The damage can be in the form of lumps, dirt, holes left by air bubbles, or scratches. To repair lumps, use a very fine piece of metal to scrape them down. If the damage is some strange fiber, it will burn away when fired and leave a space, so remove it and repair the place.
To repair the damaged parts, dip a paintbrush into the glaze-base that you have kept separate for repairing and fill them up. This makes lumps, so let it dry for a few minutes, then scrape it down to the correct height and brush off any loose glaze. Finally, using a soft brush, with thin glaze-base, smooth the part down.