Wednesday, May 08, 2013

What is a Janvier Reducing Machine?

A Janvier transfer reducing machine traces a larger than actual coin design from a galvano or epoxy shell unto the end of a piece of steel which will become the master hub.

The resulting design on the master hub is the actual diameter of the coin and in raised relief just as it will appear on the coin.

1911 image of two Janvier machines in the die-sinking department 
of the Gorham Mfg. Company of Providence, Rhode Island 

The way the machine works is that a large pattern of the design is attached to the copy-holding table (Labeled A in photo). A die is held by the chuck in the work-holding table (Labeled B).

The two tables turn at the same speed while a lever is pivoted on which one end you will find a tracer, and the other end a cutter. 

As the tracer (Labeled E) moves in and out as it rides upon the pattern, it transmits its movements via the lever to the cutter (Labeled D) which cuts a duplicate of the design into the die.

Since the fulcrum of the lever is closer to the die than the pattern, the result is a much smaller version of the original pattern. 


Post a Comment

<< Home