PMF & CNC
I held a table at Publications and Multiples Fair VIII in Baltimore April 1st & 2nd. What a time! The PMF is a thoroughly galvanizing event put on by Open Space Baltimore which brings artists of all kinds from all across the USA to sling their wares, to shop, and to trade in the PMF arena. This is a very special event which reminds me of the uniqueness of Baltimore's arts and music realm as well as announces the season of spring. Pictured below is a view from my table. I was next to Jimmy and Stuart. At my table I had for sale the Double Knot synth as well as a special kit I made for the PMF event, bearing the same initials, The Petit Mini Filter. The PMF is made up of a input preamp stage, a transistor ladder lowpass filter, a wavefolder after the filter, and a simple relaxation oscillator. The kits were a success, I dont have any more. For download and printing here is the build doc and some schematics. Edit: Now in April 2020 this doc has been superseded. Here is the updated version of the design please build this! if you need the original doc for any reason please contact me by email. Below is a pic of my display... I brought the scope to help attract the image and screen inclined. And some snacks because PMF is quite a marathon. I engraved some PCBs for the PMF kits on my CNC machine and after cutting the boards for the Fair and feeling the jolt of spring, I made some upgrades to my machine. I added two T-slot extrusions that will hopefully make the machine more rigid and provide a long term flexible hold-down system... I bought the tslot tables from Misumi, item number HFSQN4-15250 (if you google this number you'll see some other cnc diyers have pointed out this part as well...) and some 8mm nuts which slide in the t-slots. I got 1/4in by 2in by 24in pieces of aluminum from mcmaster to make adapter plates which will screw into the front and back steel angles of the cnc frame and couple to the 6mm tslots on the bottom of the extrusion. I put the nut and bolt on there like this then slid the t-slot extrusion onto the rear nuts and bolts... Then I did this on the other side where I held the nut in the tslot with an allen key and screwed in the phillips with one finger... happy spring