Guru
Joined: 07/09/2016
Location: United KingdomPosts: 2041
| Posted: 10:06am 07 Nov 2019 |
I never used PnP but I am aware of it.
I did make two small pcbs using the toner transfer method from glossy photo-paper, worked well and basically the same idea as PnP. I understand some have used glossy magazine paper also but I never tried it. I haven't persisted with the heat transfer method.
I always seem to be changing my methods because in truth I don't make a lot of small-run PCBs myself that much - my preferred method (not really PCB) for singles is (amazingly) to back-wire using really fine enameled copper wire and the net-list. I can get really good density on proto-board using this but is is time consuming - I find it quite therapeutic. No good for 100% surface mount of course. I used this method with my frequency counter that used a heap of DIP chips on an old eurocard. Only took a couple of hours to break the back of it.
For PCBs in 1s & 2s Traditionally I used to do photo-transfer but it was so infrequent I was alway hunting-for/repairing the UV exposure unit and finding that my store of light sensitive board was beyond it's sell-by date and giving poor results etc. Don't like the process for it really (expose, caustic, etch...) too many opportunities to muck up.
For small runs, I have a fool-proof method for you but it requires a laser etcher - a suitable one is available really cheaply now - with caveats(!). Simply prepare the board and spray with matt black car aerosol, then etch the pattern directly to the copper - it burns away the paint and then when you etch it with ferric or whatever, only the laser etched traces are removed... means your etchant lasts forever coz the copper load is tiny and it makes nice PCBs for ground planes etc. here's the vid that got me into it: https://www.youtube.com/watch?v=1hFNj86L7sk&t=41s ... might help you as it did me.
For multiple runs, PCBs are so cheap to get done in China now that I go to JLC for just about everything where I need three or more. The quality is really good.
my 2p
Edited 2019-11-07 21:26 by CaptainBoing