drawing straight lines with a Polargraph

Well, I have been busy with other things but hankering to get the Polargraph I got as a kit from Sandy Noble to plot lines as straight as possible.  The process wasn’t as simple as I’d expected for quite a number of reasons including, as often seems to be the case these days, an overestimation of my ability to remember …

robdrawing straight lines with a Polargraph