Although I am a bit of a tech nerd OLD tech fascinates me. Hence my beloved Technics SL-3 Linear turntable.
For those that don’t know a Linear Turntable works by tracking the needle across in a straight line via a pulley rather then on a tonearm. Its a more “tech” approach to LPs that I love the style of. You can see what I mean here on the excellent TechMoan channel https://www.youtube.com/watch?v=8gvlnEi_yHQ&t=88s (ironically the SL-6 that he shows doesn’t have the issue I am here to solve!)
Being on the really cheap end of the linear spectrum my SL-3 only has the ability to sense two record sizes. 12″ and 45. There is a rarer size format of 10″ however (that runs at 45 speed) and my Sleeping Beauty (Tchaikovsky not Disney!) record is in just that format. My Turntable senses it as a 45 so it plays at the correct speed but starts right near the end.
Now there WAS a solution supplied by the makers to solve this. Its a little plug that you use on the sensing lever to fool the turntable into thinking that it has a 12″ record on it. This has its own perils as you need to cue the start or crash your stylus in to the platter at the 12″ point! At some point my adaptor and my turntable have parted company, not surprising for a 30 year old piece of tech in all honesty.
So then, how to solve this?
When the lid is closed the lever to the right that my finger is pressing is pushed. If there is a 12″ on the platter it hits the rim and slides left. If there isn’t it just comes downwards.
My understanding was that the adaptor slotted onto the peg holding it in the 12″ position. When the lid was closed the lever would push but be fooled into thinking the record on the platter was bigger then it is.
A simple solution of course is to jam the pin. This is 3D printing though and I think we can be rather more elegant then that.
Its measuring time.
All of the relevant, measurements were taken and I headed downstairs to, oh wait, the measurement I forgot was taken and, well the OTHER , measurement i forgot was taken as well and I finally headed to my PC, today’s step aerobics completed.
My software of choice is Fusion360 so a quick sketch of the the turntable is entered to allow me to design in the part i need.
Then to export to the printer. The print itself took a whole 6 minutes and it worked perfectly.
It fits perfectly and works like a charm. This is a great example of how 3D fabrication can solve really obscure problems elegantly and robustly. I am sure that in some obscure audiophile corner of the internet there is someone selling these at £20 a pop!