In this post we bring you the second part of the list of the most common problems that can occur during glazing and their solutions.
To go to the first part, click here .
6. ENAMEL BECOMES BRITTLE
It is due to the fact that the mixture contains an excess of catalyst, when. Mixing with a scale and following the proportions required in our technical data sheets for each catalyst ensures a resistant, non-cracking enamel.
7. WATERS” APPEAR WHEN COLORS ARE MIXED WITH WHITE.
When water appears, it is because there has been a dissociation of pigments and there is a problem of tension, especially with the white color. To homogenize the color mixture, it should be added to the mixture in a proportion of 1% to 5%. ADDITIVE O.L to the mixture in proportion of 1% to 5%.
8. COLORLESS LAYER DOES NOT RUN OR RETRACT WHEN APPLIED OVER ANOTHER LAYER.
When applying colorless enamel on an enamel base, it may not spread properly or may even retract. This is because the base coat had ADITIVO O.L. in it.
The solution is to add to the colorless enamel mixture ADITIVO O.L. in a proportion of 1/1000
9. GLAZING FLAT PARTS WITHOUT EDGES
THE ENAMEL EXCEEDS THE LIMITS OF THE PART/LABEL
There is probably an excess of enamel that the piece cannot contain. The solution lies in applying a smaller amount of enamel and ensuring that the ambient temperature does not exceed 25º (which would make the product more fluid).
To avoid these problems, we recommend mixing directly with our DomingFlex B, created especially for parts without edges and labels.
THE COLORLESS ENAMEL DOES NOT SPREAD OR CHANGE COLOR WHEN IT COMES OUT OF THE KILN.
Problem with the media type or the printed inks (labels) so trying another type would solve the problem.
10. ENAMELING CURVED AND SEMI-CURVED PARTS
THE ENAMEL HANGS IN THE SHAPE OF A DROP
Excessive glaze has been applied. The solution is to apply enamel in small quantities, maximum 0.2 mm or 200 microns.
BUBBLES AND MICROBUBBLES APPEAR IN COLORLESS GLAZES
The mixture has been stirred too vigorously, generating too much air. In this case, if once enameled bubbles are visible on the surface of the piece, it will be sufficient to apply thermal shock with a soft flame (blowtorch) or use the vacuum pump to remove bubbles from the mixture.
OR RIPPLES ARE PRODUCED OR THE SURFACE BECOMES UNEVEN
Produced by glazing needle marks, the use of a brush or other means of application, these imperfections disappear by applying light heat with a blowtorch.
GLAZE HANGS AND DRIPS INSIDE THE KILN
The enamel becomes more fluid with temperature. The reason may be that the baking time is too short (up to the gel point) or that the oven is too hot. It is important that the enamel of the piece reaches the gel point before putting it in the oven and ensure that the oven temperature is between 30-40º.
Remember that the Coniex Technical Team is at your disposal for any consultation on the subject.