At this point the only thing holding me back from a cheap supply of swappable carbon fiber arm tubes in any length I like was the contact boards to make the cartridge wire to tonearm base connection point. I had the spare I pulled from the damaged arm tube for my prototype 12in arm, but I'd like to have 5 or 6 carbon arm tubes with cartridges mounted eventually, and finding that many spare tubes for a 40 year old tonearm was not going to be easy.
I began researching custom circuit board design and manufacturing. After all, the contact board is just a 0.6mm thick piece of PCB with some solder pads on it, in a custom shape to fit the terminal block at the back of the arm tube.
It turns out there are plenty of PCB makers that will make a small batch of PCBs if you supply them with the files. The problem was that the file format they wanted (something called a Gerber file) was a multi-layered file that required some pretty heavy knowledge to create properly. The software to create Gerber files was not easy to learn and I started thinking about how I could get the files I needed without cramming a college course in circuit board design.
Then I remembered Fiverr. It's a website that people use to get logos or drawings made by graphic designers for a $5 or so. Just quick, one-off files for a little money. Nothing you'd use to rebrand a huge corporation but helpful if you were making your own website and didn't have any logo creation skills. I wondered if anyone on there could create Gerber files for my simple PCB I needed. Sure enough, there was an Electrical Engineer on there offering his services for Gerber file creation. He was super friendly, interested in my project, and had my files ready in a couple of hours.
I sent the files off to PCBWay and had a quote ($60 for 25 boards with Immersion Gold coating on the solder pads) and had my boards in my hands a week later.
I soldered one into my 'parts' unit spare arm tube and mounted my AT OC9XSL to it and I'm happy to report the custom contact boards work great. They fit into the terminal block and line up just like stock with the spring loaded contacts inside the tonearm base. I'm now good to go for as many DIY arm tubes as I could ever need.
