THE PANTAGRAPH
For copying designs, for reducing or enlarging, this old-fashioned instrument may be easily constructed. [Fig. 208] shows it made of four strips of thin wood of equal length. Either pine or white wood will answer. The pieces have to be squared, twenty-five inches long, three quarters of an inch wide, and a quarter inch thick.
Bore or drill through the four pieces held in a vise, and space the holes shown in drawing three inches apart, 1⁄8 inch in size.
Fig. 208. The pantagraph
When put together, a, b and c should be in line. Point a is to remain fixed, the pantagraph being free to move around it as a pivot. To accomplish this, cut out a block, as shown at x, with a hole drilled at the centre for pivot, and two others for screwing to the drawing table or board.
The pin for this pivot may be a thick flat-head wire nail, screw, or even a screw eye. The joints d, e, and f are also pivots moving with the pantagraph. They may consist of thumb screws, and nuts, or screw eyes, and must move freely, yet without play.
Points b and c are to be interchangeable, one having a tracing point, the other a pencil.
The tracing point may be a wire nail, rivet, or screw, with the point filed sharp, and then slightly rounded. The pencil point should be a piece of lead pencil, whittled down to such a size as to pass through the hole at b and c, and make a snug fit.