Plotter Pen Holders
| The CNC machines can be used as plotters. The idea is
straightforward but for something so simple it is surprising how
annoying the process can be. A pen does not fit in a router collet, and wiring or taping the pen to the Z axis does not provide enough support.  The units shown on the right were put together to remedy this. They are made of copper fittings and pipe, and are designed to use plotter pins. Plotter pens are going the way of printer ink ribbons, but are still available at some print suppliers and of course on Ebay. A box of mismatched remnants were picked up here at pennies on the dollar from a local supplier who was glad to get the odd inventory out of his shop. The middle and right holders were made from copper 3/8 inch male adapters. One is shown in the upper right of the photo. An old router bit and Dremel bit were soldered to the ends of the couplers. Screws were tapped into the right coupler so it could hold smaller pens. The middle was left untapped; the larger pens could be pressed into place. The male adapters were filed-ground-sanded while being turned by a drill to remove the threads. This is only for appearance and is not required. The unit on the left is made of a 1/2 inch copper cap and a coupler which are butt joint soldered. A section of 1/2 inch pipe slides inside the coupler and a spring adds tension. A slot is drilled into the sliding section of pipe that matches a screw in the side of the pipe cap. This screw prevents the pipe from falling out when the axis is raised. The spring loaded holder is the most forgiving to use, but the others are simpler to make. Now when trial runs are done, a pen can be put in the router collet in place of a bit. These holders help to keep simple jobs simple. .......................
The image on the left below is a model that used the CNC machine as a plotter. A pen was placed in the router's collet and the print was drawn on foam board. The model was then cut out and assembled. This process helped in the visualization of the gazebo/conservatory before the actual structure was built.   |