Blisters

1st stage burnout hold too short

Ensure 1st stage burnout hold time at 220ºC is 4.5 hours. If problem still occurs, increase hold to 5.5 hours.

Flasks de-wax at too high a temperature

Do NOT exceed 240ºC in the 1st-stage burnout (see burnout section).

Flasks placed in furnace too soon after investing

Do NOT burn out before min. 1 hour after investing.

Flask placed too close to or touching elements

Leave a minimum of 50mm gap between flasks and elements.