One of the first things necessary for high quality embossing work is a good counter die. A very effective counter die can be made with a material called Thermomat Board. Thermomat is a fiberboard that has glue impregnated into the fibers. When heated and put under pressure, the counter die image area becomes very hard and durable. Thermomat can also be used to build up the make-ready to get more relief.
The following procedure and materials will assist you in assembling an effective counter die.
1. Glue Phenolic Board to the platen surface.
2. Rough up the Phenolic with sandpaper or a cutting knife where the Thermomat Board is to be glued.
3. Glue Thermomat to Phenolic
4. Put press “on Impression” and take 15-20 hits on the die.
5. Cut away all of the board that is not in the image area.
6. Cover with polyurethane ½ mill, release film and put the press on top, centered, with about 250 degrees on the hot plate and heat Thermomat for about 10-15 minutes.
7. If more depth is needed, glue on another sheet of Thermomat and repeat the above process.