flexPCB DIY
here we show etching an electrical layout on a flexible composite pcb.
== Flexible pcb ==
Pyralux (LF9220R) by DUPONT.
composed of
• copper foil (70 um)
• glued (25 um)
• kapton tape (51 um)
in total ~150 um thick
==Photosensitive dry film==
Riston (MM540) by DUPONT
note we had bad luck with non brands from the open markets.
possible exposed to sun before shipping. inspect on arrivle
the film should have a light bluish tint, but mostly transparent
the development solution is a mix of 1gr to 100 ml of sodium Carbonate and water
we use
• 4gr sodium carbonate
• 400ml of water
source for pyralux and photoresistive dry film - http://www.tech-place.com/en/pyralux/...
==Etching==
TLDR
A typical PCB etching solution contains:
• 1000 ml water
• about 250 g sodium peroxodisulfate
bring it to 45c and circulate solution with oxygen (bubbles)
our etching solution (NaPS) is based on this guide
https://frgmnt.org/naps-etchant-chemi...
we are https://idiot.io