So the 3D printed belts… My main work is actually Software and Electronics, but I have a long history with HiFi, and audio really is my first love. I was brought up with some amazing hifi in the house and my older brother was into electronics and he and a family friend would build amps, mixers and all kinds of custom gear. Looking back it was an amazing upbringing being exposed to lots of gear (usually with the lid off undergoing some sort of modification) and quality audio.
Fast forward to me leaving school. I worked in a workshop back in the 80’s/90s repairing all kinds of cool pro video gear for the broadcast industry, and we did fair but if domestic gear too. This fed my love of audio gear quite well for a long time.
But my work changed quite suddenly when work needed me to do some programming for a project and I got sucked into the software industry, but audio and HiFi never left me.
Anyway, fairly recently I started chatting with the amazing Maurizio Miserere, a Canadian gentleman on instagram (@m2circuits) that specializes in R2R and cassette repair, and we helped each other out with some projects and became really good friends. Seeing him work on gear and making his own cool pre amps inspired me to think seriously about making some gear again.
I already had a background project on the go which was a special phono stage and I also wanted to do a bit of a showcase with dbx encoded vinyl discs, which I had a few of, but no decoder. The stand alone ones like the dbx 224/228 are pretty expensive, but I was aware that there were quite a lot of cassette decks that had dbx on them with disc decode function, so I started to look for a tape deck that I could essentially gut for its dbx decoder.
So I managed to get a “for parts” Technics RS-M228X for £20 off ebay, and it duly arrived. I of course immediately took the lid off and started to look at how to remove the dbx board which turned out to be pretty simple. But the more I looked at the deck I couldn’t bring myself to end its life, because, it was such a nice deck and so I decided to restore it instead. From this I got the cassette deck bug and started to collect “for parts” decks from ebay to restore and sell on to new forever homes. I’m still tripping over a fair collect in my tiny workshop!
Of course they were all going to need belts so I ordered what were supposedly premium belts in from suppliers, including some from a well known supplier. Around the same time a local HiFi trader was already bringing me repairs, like turntables and amps, but one day he turned up with an Aiwa AD-F660. And after a bit of research I could see that it was a much loved deck and very capable especially in the w&f area.
Anyway belts (a lot of them) finally arrived and I eagerly fitted them to the mech which I had been busy stripping, cleaning and lubricating. And initially it sounded ok but I knew it wasn’t right and I’m really keen on measuring things to remove subjectivism and I was so disappointed with the W&F figures when I measured it, I could have cried. And I wasn’t sure if it was some non obvious fault with the mech so I ended up stripping it a number of times including the motor and various areas but only got marginal improvements.
I eventually started reading through tapeheads.net threads and started to suspect the belts. There was some interesting info about “finishing” belts which involved sanding belts to improve them and I tried this and did get some good results but by the time w&f was acceptable the belts were so thin that it was not a good long term solution. So I was scratching my head at this point. Lovely 660 on the bench and 12 other decks all in need of good belts and no solution!
Now at this point, I had already been 3D printing stuff for about 3yr and had heard of flexible filaments and the frustration with rubber belts made me seriously think about trying it. And to be honest in my head I thought I’d just buy a filament and start printing belts. I had no idea it would take me over a year just to find a suitable filament and then a further year to work out how to print them with enough precision to do justice to the likes of the 660 and some of the other decks I had.
It was quite a journey, and one thing that became apparent very quickly was that my printer wasn’t good enough to do it, but I didn’t have the cash to splash on a new one, but also I didn’t fully understand some of the problems I was experiencing in the printing of them, and so buying a new printer was a risk. So I just had to keep printing and try to understand each issue and resolve it either with slicer settings or fixing/upgrading the printer and keep going until I got reliable results. My printer is now somewhat of a Frankenstein.
What’s bizarre though is that early on by some fluke I did manage to print some good belts and so despite all the failures I knew it was possible. The problems I encountered were endless. Nozzle size, print speed, elephant’s foot, extruder issues, temperature issues.. Then there was the flexible filament itself – for some months I was printing with one filament I thought was suitable and then I got busy with some software work and when I returned to the deck and tested, the material had deformed and the belts were useless. Then there was also the reduction ratio needed – the material is somewhat different to traditional rubber, so getting the right size was a lot of trail and error.
Whats good about the material I settled on is its really stable stuff, probably more stable than real rubber belts, which as you know can go to ‘goo’ eventually. I subjected it to some pretty harsh treatment and its resilience is impressive. I think these belts will last a very long time.
In most cases these belts can help a belt driven deck meet or exceed its original spec which is a really satisfying to see.
There you are. It was quite a ride. I made some friends along the way who have helped and continue to help me test new belts, and I learned and continue to learn a lot from them.
So in 2025 I have started offering a belt printing service and I have many popular deck belts available.
Pete.
