Devitrification Overspray Made
From Borax And Water

Using an overspray can help prevent devitrification affecting the appearance of your fused glass item.

Devitrification can appear on glass surfaces as glass cools. It is a scummy white or hazy, or rough surface on the fused glass.

Some fusing glasses may be more subject to this than others.

Using an overspray can help overcome this problem.

Contamination on the glass surface can cause this problem to appear.

Always ensure your glass is completely clean prior to fusing in the glass kiln.

Glass held too long in the pre-molten temperature range about 1300 F (700 C) can also cause this problem to arise.

The objective should be to move the glass through this range quickly, either to the glass fusing temperature or down to near the annealing point.

"Crash cool' by venting the kiln from the fusing temperature down to just above the annealing zone.

Before fusing glass many artists apply a "devit spray" (overspray) to the glass, it can be either sprayed or brushed thinly across the surface.

The spray protects the glass during the fusing cycle.

You still need to have clean glass and a satisfactory firing schedule.

Dry completely before placing in glass fusing kiln.

This spray is easy and cheap to make as per the following instructions.


1-teaspoon borax regular cleaning powder to one cup of water. Distilled water is preferred.

Measurement does not need to be precise.

A few drops of dishwashing soap or Klr-fire will give the spray a better spread.


Use warm or heated water, add borax to water and mix.

Do not boil mixture.

If you place water and powder in small jar, cover with lid and shake.

This will give you a good mixture.

Shake well before use, either brush on or put mixture into small hand sprayer and spray on fusing glass.


Label Jar

Do not swallow mixture.

Wash hands immediately after use.

Powdered borax can be fatal to small animals.

Avoid long-term exposure to borax, as this can be harmful.

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