Understanding the Pad Printing Pad

Material of the Pad Printing Pad

This topic refers not only to the material of the pad itself, but also the base onto which the pad is mounted. For example, you may order pads mounted onto aluminium bases rather than wooden ones, the advantage being that the pads can be mounted very accurately on the machine. Pads with wooden bases rarely are supplied with holes drilled into the bases for attaching to the pad holder of the machine. This means that the printer usually screws the pad in himself, ma king it difficult to get repeatable pad positioning. Also, with wooden bases, you use wood screws. If these screws are taken on and off several times, the base becomes loose. On several occasions, we have seen pads literally fall off the machine during the print cycle because of this problem.

Aluminium bases are better because they come with predrilled holes, so there is only one position to mount the pad on the holder or backing plate, also, unless you have a very heavy-handed press operator, the threads of the screws are not easily damaged. This means that it is simple and quick for press operators to mount or replace pads. Choosing the proper pad hardness for a job is a matter of experimentation and experience.

Similarly, if a setup requires multiple pads (such as a matrix), aluminium bases are preferable because they will make pad positioning easier and more repeatable. One further advantage of aluminium bases is that they can be recycled with your pad supplier.

If you are using a long-bar pad that does not have an aluminium backing, then back the pad with either aluminium or a thicker piece of wood. This will prevent the base from bending when it comes into contact with either the cliche or the substrate. Such blending can cause print distortion or prevent the pad from picking up the image entirely.

Recently, pads have appeared on the market that are mouided onto a nylon-type base material, offering the advantages of aIuminiurn at less expense. These pads are also delivered in a protective clear vacuum-formed plastic that you can use to store the pads, while they are not in use.

Regarding the pad itself, virtually all pads today are made of silicone rubber. The first printing pads were made of gelatine, although there is some evidence that inflated pig bladders were used in the UK pottery industry at the beginning of the 20th century. Only a limited range of pad shapes were used at that time due to the mechanical properties of the gelatine. The printing surface was much flatter than modern pads since gelatine lacks the elasticity of modern silicone rubbers. These older shapes have come back into fashion with the very hard pads currently being used in compact-disc decorating.

Certain pads can be recycled (sometimes called "recovered" or "resheathed"). Large pads are very expensive. To reduce the cost of replacing pads, some printers will send their worn or damaged pads back to their supplier. the supplier cuts the surface of the pad away and inserts the remaining rubber into the mould where the replacement pads are created, reducing the amount of new silicone rubber that is needed. The new material cures and bonds onto the old rubber and the finished pad performs like new, with a savings of up to 50% over the cost of a new pad. If your pad has been split or broken dawn internally, however, it cannot be recycled.

Some pad manufacturers will use recycled material and mix it with new silicone rubber. As long as the pad surface is "virgin" silicone rubber, this p r a f ice is perfectly acceptable.

Shape and Size of The Pad Printing Pad.

Shape is the most important variable in selecting a pad.

Hardness of the Pad Printing Pad

The hardness of the pad is normally determined by the amount of silicon oil used when the pad is moulded.

Surface Finish of the Pad Printing Pad

Throughout the pad-printing industry, the custom practice among pad manufacturers is to furnish pads with a high gloss finish.

Material of the Pad Printing Pad

This topic refers not only to the material of the pad itself, but also the base onto which the pad is mounted.

Special Printing Pads for Large Images

In some situations, a large image area must be printed and the machine does not have the power to compress such a heavy pad in a smooth motion.

Quality Control of Pad Printing Pads

Poor-quality consurnables like pads can destroy the performance of the printing machine.

Pad Printing Pad Life

Next to "What should I use?", the most difficult question to answer is "How long should a pad last?"