Shenhua Printing: Practical Installation and Layout Tips for Ejection Rubber

While selecting the right ejection rubber is crucial, proper installation and layout are equally important for achieving optimal die cutting results. Many common die cutting issues, such as uneven cutting, sticking, and premature rubber failure, are not caused by poor rubber quality but by incorrect installation or poor layout design. With 25 years of experience in the printing consumables industry, Shenhua Printing shares practical installation and layout tips that can significantly improve ejection rubber performance and extend its service life.

The first and most important layout principle is maintaining the correct distance between the ejection rubber and the die blade. If the rubber is too close to the blade, it will be cut by the blade during stamping, leading to rapid wear and tear. If it is too far away, it will not provide sufficient support and ejection force, resulting in incomplete ejection and sticking. Shenhua Printing recommends maintaining a distance of 0.5-1mm between the rubber and the blade for most applications. For thin materials like labels and films, a distance of 0.3-0.5mm is more appropriate, while for thick materials like corrugated board, a distance of 1-1.5mm is better.

Special attention should be paid to corners and sharp angles, which are the most prone to failure. At sharp corners, the ejection rubber should be cut into small pieces and placed separately, rather than using a single continuous piece. This prevents the rubber from stretching and tearing at the corners during repeated stamping. Additionally, the rubber at corners should be slightly thicker than the rubber on straight edges to compensate for the higher pressure in these areas.

For waste stripping the layout of ejection rubber on the waste edges is critical. The rubber on the waste edges should be slightly harder and thicker than the rubber on the product areas to provide stronger ejection force and ensure clean waste removal. Shenhua Printing suggests placing rubber strips every 2-3cm along the waste edges, with additional rubber pieces at the junctions of waste strips to prevent waste breakage.

When installing ejection rubber, always clean the die board surface thoroughly with alcohol to remove any dust, oil, or old adhesive residue. This ensures strong adhesion between the rubber and the die board. Apply the rubber slowly from one end to the other, pressing firmly with a roller to eliminate air bubbles. Air bubbles trapped under the rubber will cause uneven pressure distribution and premature collapse. Finally, allow the adhesive to cure for at least 24 hours before putting the die into production for maximum bond strength.