Troubleshooting Four Common Pad Printing Pad Defects

Bubble Defect

Bubbles on or inside the pad block clear ink pickup. Fast stirring drags air in. Pouring from height folds air under the surface. Skipping vacuum degassing leaves micro bubbles. Stir slowly along the wall, pour along the mold wall and run vacuum for three to five minutes.

Tearing Defect

A pad that cracks after a few uses usually has too much cure agent. Excess cure agent produces a brittle network. Long storage or contact with sulfur, phosphorus and amine materials also weakens cross linking. Weigh 2 to 3 parts cure agent per hundred and keep stock sealed away from vulcanizing stations.

Deformation Defect

An uneven pad that does not sit flat comes from a tilted mold or aggressive pouring. Level the mold first. Let the liquid rise from the lowest point. Rest the demolded pad on a flat table until fully cured before trimming.

Blurred Transfer

Ragged edges often mean the pad hardness does not match the graphic. Fine curved graphics need a softer pad such as HY-916. Flat simple graphics work with HY-901 or 902. A hard pad cannot flex to contact a curved substrate evenly.