Engraving pantograph

[mklotz]

I made this miniature pantograph to engrave name plates and such, primarily for the models I make but also for other practical purposes.

It's a simple, fixed 2:1 reduction ratio mounted on a bearing so it can be swung up out of the way to inspect the progress of the engraving and mount/dismount workpieces easily. It carries a clamp that can grasp the handpieces of flexible cable tools such as the Foredom and Dremel.

The characters are traced from a Rapidograph (TM) template. (Remember those? Back in the dark ages of drafting they were all the rage.)

Here's a picture of the pantograph flipped back on its bearing to show the workpiece clamped in place.

The stylus used to track the letters in the template has a tiny, turned-down tip sized to match the grooves in the template. The other end of the stylus has a different diameter tip to match a different font on the template. A brass cover for the other end protects the stylus tip and functions as a handle used to guide the stylus.

And here's an example of the type of text produced.

Bronze or hard brass are the best materials for engraving. For an engraving tool I use either a very tiny spherical bur or grind my own pyramidal point tools on 1/8" drill rod.

I should mention that there is a drawback to using the Rapidograph template as a guide. The template has to be relocated a variable distance for each letter while the engraving bur always moves the same distance to the next letter.

In practice, I solve this problem by ruling lines on a piece of sheet metal taped to the base under the template. This provides a reference for where to place the next template letter. Sheet metal is used in place of a paper guide because the rather tiny tip on the stylus tends to catch and tear paper while it glides smoothly over metal.