Extract Without Breaking

The most common extraction mistake is rotating the impression as if unscrewing a part. Plastiform impressions must be pulled straight out.

Basic Rule

Pull in a straight line, in the direction that gives the lowest removal constraint. Do not twist, rock, or unscrew.

Before Extraction

1. Confirm polymerization is complete. Press the drop test with a fingernail. If it marks, wait longer.
2. Identify the extraction direction. For through holes, choose the side with the larger opening.
3. Ensure there is enough grip. A demolding ring or a surplus grip of about 1 cm is recommended.

During Extraction

1. Grip the impression firmly.
2. Pull steadily in one direction until the impression clears the part.
3. For Flexible impressions, expect the material to deform as it passes undercuts. It will return to shape within seconds.

If the Impression Resists

• Recalculate the removal constraint. You may have underestimated it.
• Switch to a more flexible product for the next attempt.
• Consider a partial impression if a full diameter is not required.
• For extreme constraints, use the temporary void and reinjection technique described in Removal Constraint.

After Extraction

Inspect the impression immediately. Reject it if you see tears, bubbles in the measured zone, or uncured areas. Do not measure a damaged impression.