Plastics Decorating - January/February 2008 - (Page 41) The first is to use a pad with a hollow interior that provides the same surface hardness. This technique also reduces the cost of silicone rubber for such a large pad. The second option is a dual-hardness pad, where the core of the pad is made of a softer material and the outer layer is the harder rubber. Both methods can help, but the second produces a more stable pad. (A third option, of course, would be to use a different imaging process such as screenprinting for larger image areas.) Quality Control of Pads Poor-quality consumables like pads can destroy the performance of the printing machine. When you receive pads from your supplier, it’s vitally important before accepting them to check the pads for the following: • Blemishes on the print surface. • Foreign particles in the print surface, such as wood splinters. • ‘Nipples’ on the print surface. • Firm attachment of the pad to the backing plate. (The pad should be secure, with no air bubbles that will cause the rubber to come away from the base.) • Hardness within +2 Shore (using your durometer gauge). • Positioning on the backing plate. (It should be concentric, with its vertical center line at a 90° angle to the backing.) • Height (which is particularly important in multiple-pad applications). Report any defects to your pad supplier immediately so that replacement pads can be furnished. Pad Life Next to “What should I use?”, the most difficult question to answer is “How long should a pad last?” Pads are like most things in life: the better you treat them, the longer they will last. Mechanical damage, aggressive solvents, and poor storage all take their toll. But the real killer is a careless operator. Some press operators have been known to pull a pad completely off its mounting plate during cleaning. If you make your staff aware of how much pads cost, they may treat them with more care. It isn’t unusual for pads to last 50,000 prints; however, going substantially over that amount is not common. Conversely, some pads are irreparably damaged before they print a single item. Usually, this results from a poor set-up, when the downward motion of the pad during ink pick-up or deposition is far too long, resulting in the destruction of the pad. continued on next page Custom dual-head heat transfer Apparel (HT300 Series) Roll-on heat transfer (Model BMR6) ENGINEERED BUILT RIGHT PRICED RIGHT 41 http://www.trekkequipment.com http://www.trekkequipment.com
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.