Microset 121 Forming Putty is a two-part synthetic rubber compound designed for macroscopic moulding of surface shape and form. The product is supplied in two versions, fast curing 121F and slow curing 121S, to facilitate ease of use over a wide range of temperatures.
Part A (yellow) and Part B (blue) are mixed in equal amounts by hand, until the compound is of a uniform colour. The mixed compound is then pressed firmly onto the area of interest and left to cure. Additional amounts of putty can be applied to build up thickness or increase the area of coverage. The mixed compound cures to form a hard but flexible rubber.
One important use of Microset 121 putty is for producing a rigid backing for the more flexible Microset 101 replicating compounds. In order to use this putty in this way, first produce a Microset 101 replica of the area of interest. Allow the replica to cure but do not remove it from the surface. Apply mixed 121 putty to the back of the Microset 101 replica to the required thickness and allow to cure. The putty will bond to the Microset 101 replica and act as a dimensional support.