Ed and his 3D Scaling Pantograph.

It is an inescapable truth of freelance working for creative companies that you are rarely in a position to show or talk about the work you are engaged in, or have just completed. Issues of client confidentiality, and the fact that much of the work is usually a long way from entering the public domain mean you can’t show anyone what you’ve been making for quite a long time after the event. Hence the lack of “making” content on the blog for a long while.

Prompted by a recent visit to the studio of a sculptor friend, this is about to change however, as it has nudged me into digging a project out of the archive in readiness to post about it.

I first met Ed up at the Ace Cafe, a favoured north London haunt of motorcyclists, where I got talking to him about his fabulous Moto Guzzi. When we discovered what each of us did for a living, and dug a little deeper, it became clear we had more in common that purely an appreciation of personally customised motorbikes. Ed mentioned that he was interested in building a 3D Pantograph, and I had completed the construction of such a device not that long previously. Needless to say he was interested in understanding what my project had revealed regarding these rather esoteric bits of equipment and a good many knowledge sharing conversations ensued.

Before going any further though, it is probably best to try explain what a 3D pantograph is exactly. I will try and be brief. A pantograph is essentially a scaling machine that allows the operator to enlarge, and in some cases reduce, the size of an image or object. They are more commonly found in the 2-dimensional realm where they are used to trace lettering or pictures for engraving and such like. Being utterly analogue in their function they have now been generally superseded in most applications by digital technology, so they are rare things to come across. Working from a fixed pivot point, two pointers, connected by a series of pivoting arms allow the operator to follow an image with one pointer whilst the other creates a replica of that image on another surface at a greater scale, like 2:1 say. In 3 dimensions the principle is the same though in this case the first pointer follows the surface of an object, positioned on a turntable, while the second allows the operator to create a scaled up or reduced version of that point in space on a second turntable nearby. If this doesn’t make sense, then I hope that seeing some images and a short film will help to make things clearer.

The pantograph pivot and counterweight assembly.

Last weeks visit to Ed’s studio in Camberwell, South London was to finally see the pantograph he had built. It was impressive. Through our earlier discussions we had figured out that these machines could take many forms, it is the core geometry which provides the link between different designs. So not surprisingly Ed’s machine is a very different looking beast to the one I built, and amply demonstrates how a different “brief”, ie what you want to make with it,  effects the final design and layout of the machine. Here’s a link to the studio website where you will find a great stop frame film of the guys building their machine and then using it to cut complex forms out of large blocks of expanded polystyrene with a hot wire, and other images. When I visited the studio last week the hot wire had been replaced by a high speed cutting head which the guys had used to carve even more complex forms from similar blocks. You will also see that the machine consists of the two main elements required for the pantograph to work, a pivoting arm that holds the “pointers” and a pair of connected turntables supporting the final piece and the model from which it is being traced.

The business end, a high speed cutting head.

In the next post I’ll reveal the details of the machine I put together for an artist, and expand a bit more on how these things work.