Printing Carbon / CP Pot Tracks - UK Vintage Radio Repair and Restoration Discussion Forum

knobtwiddler · 24th Feb 2021, 3:42 pm

Hi,

Has anyone here ever been involved in printing conductive tracks in pots? To my knowledge, there's about one firm left doing it in the UK (for audio anyway), and their staff are flat out with current work, so unable to take on new projects.

This makes me wonder, just how much work is there in it? And how specialist is the equipment needed? I once visited P+G's factory in Wales, but this was about 20 years ago, and I didn't take notes on exactly what machines were being used. I've spoken with a firm in Switzerland who print tracks, but they're saying they want a 25,000 MOQ...

Can someone give me an outline of the kit needed, and what the various pitfalls are? I'm assuming that getting the track compound right is the first thing, and the next is getting a precise distribution across the track. PCB manufacturing technology has come along in leaps and bounds in recent times, so what's to stop you printing resistive tracks?

Thank you in advance!

NB - I posted a similar thread a while back. It would be appreciated if we could focus on the art of track printing, not the commercial imperative.

https://www.vintage-radio.net/forum/...d.php?t=174352

Radio Wrangler · 24th Feb 2021, 5:49 pm

What you want is conductive plastic thread for a 3D printer.

In years gone by with an idea like that, I'd have patented it!

You can always make the pots large. In the audio world this will make them look more imperious and therefore expensive

David

knobtwiddler · 24th Feb 2021, 7:00 pm

That is a great idea, thank you! I shall log into the Patent Office website now..

Part of the problem will be finding something that's not only mirror smooth, but durable. The best pot in current production (for hifi) is the TKD. I'm not sure what's in the CP amalgam. I do know that, aside from excellent gang error matching, they are supremely durable.

>You can always make the pots large. In the audio world this will make them >look more imperious and therefore expensive

You know the market too well.We could find somwhere to use silk or hemp - as there are components that supposedly contain these fibres, so they must sound better!

Have you ever seen the ALPS RK50 pot? They go for several hundred quid a pop. I believe they were designed at the behest of Sony. I have a couple. I must check and see if their L/R matching is better than smaller ones (it ought to be, in theory).

Thanks,

24th Feb 2021, 3:42 pm	#1
knobtwiddler Octode Join Date: Mar 2016 Location: London, UK. Posts: 1,046	Printing Carbon / CP Pot Tracks Hi, Has anyone here ever been involved in printing conductive tracks in pots? To my knowledge, there's about one firm left doing it in the UK (for audio anyway), and their staff are flat out with current work, so unable to take on new projects. This makes me wonder, just how much work is there in it? And how specialist is the equipment needed? I once visited P+G's factory in Wales, but this was about 20 years ago, and I didn't take notes on exactly what machines were being used. I've spoken with a firm in Switzerland who print tracks, but they're saying they want a 25,000 MOQ... Can someone give me an outline of the kit needed, and what the various pitfalls are? I'm assuming that getting the track compound right is the first thing, and the next is getting a precise distribution across the track. PCB manufacturing technology has come along in leaps and bounds in recent times, so what's to stop you printing resistive tracks? Thank you in advance! NB - I posted a similar thread a while back. It would be appreciated if we could focus on the art of track printing, not the commercial imperative. https://www.vintage-radio.net/forum/...d.php?t=174352

24th Feb 2021, 5:49 pm	#2
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,863	Re: Printing Carbon / CP Pot Tracks What you want is conductive plastic thread for a 3D printer. In years gone by with an idea like that, I'd have patented it! You can always make the pots large. In the audio world this will make them look more imperious and therefore expensive David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

24th Feb 2021, 7:00 pm	#3
knobtwiddler Octode Join Date: Mar 2016 Location: London, UK. Posts: 1,046	Re: Printing Carbon / CP Pot Tracks That is a great idea, thank you! I shall log into the Patent Office website now.. Part of the problem will be finding something that's not only mirror smooth, but durable. The best pot in current production (for hifi) is the TKD. I'm not sure what's in the CP amalgam. I do know that, aside from excellent gang error matching, they are supremely durable. >You can always make the pots large. In the audio world this will make them >look more imperious and therefore expensive You know the market too well.We could find somwhere to use silk or hemp - as there are components that supposedly contain these fibres, so they must sound better! Have you ever seen the ALPS RK50 pot? They go for several hundred quid a pop. I believe they were designed at the behest of Sony. I have a couple. I must check and see if their L/R matching is better than smaller ones (it ought to be, in theory). Thanks,