Dimensions Vary Between Impressions
Plastiform has no dimensional shrinkage, so inconsistent dimensions come from the conditions. They depend on the surface, the temperature, the moment of extraction, or the way you measure the impression.
Surface and Temperature
A contaminated surface distorts the impression, so degrease before every impression.
Extreme ambient temperatures also change the result, so work at a stable room temperature. Let the impression and the part reach workshop temperature before measuring. When you can, make and measure the impression at the same temperature.
Extraction Too Early
An impression removed before it is hard enough loses accuracy. Check the test drop with a fingernail, then measure only after complete polymerization, as given on the technical sheet.
The Way It Is Measured
A large or thin impression can deform under its own weight, so rest it on a support with no stress. Too much contact pressure from the instrument also deforms the impression.
Dust sticks to the impression, which is slightly electrostatic, so clean it with Plastin.
Use the same reference orientation each time, and repeat the reading at least twice.
