Sole molding operations

3. Molded soles are different from calendered soles.
Calendered soles are cut from unvulcanized sheet
rubber (using cutting dies similar to cookie cutters),
and they are able to co-vulcanize with the boot while
they are stuck to it. Because they are cut from flat
sheet rubber, they are less expensive to produce.
Molded soles are produced by placing rubber in a mold
cavity, closing the mold and compressing it in a press.
This method vulcanizes the sole completely, and gives
you more options in the design of the sole. It also
allows you to use specialized rubber compounds that
may be difficult to process smoothly, for better
abrasion resistance, oil resistance, or other
applications.

As you can see in this video, molding is a slow process,
so molded soles are more expensive to produce.

Category:

Education

Tags:

• rubber
• sole
• outsole
• mold
• molding

[ffairlane57]

These appear to be one-color soles.  Many soles these days have more than one color, and include a third mold plate on top.

[fog152]

Amazing really