Kreyren/kreyren

Reverse-engineering of Solder Mask

Opened this issue · 1 comments

Issue dedicated to reverse-engineering the composition with the intention to improve it


image

Solder Mask is used to cover up exposed copper tracks on a Printed Circuit Boards as shown in https://youtu.be/M3VEmBE2Nh0?t=2619 which hardens under UV light and bubbles at 300C.

Available online on e.g. https://www.hotair.cz/detail/pasty-ciny-lepidla/uv-vytvrditelny-lak-pro-nepajivou-masku-cerny.html

Expectations

  1. electrically insulating liquid used to protect the copper tracks on fibreglass board.

  2. Does not interfiere with SMD soldering using direct heat of +235~300 C to melt lead/tin with the use of "flux" (liquid that transfers the heat evenly and evaporates at +-280 C).

  3. Doesn't react with isopropyl alcohol used in supersonic cleaner to clean the board.

Motivation

  • Custom colors of PCBs
  • Not economical in Europe (costs 12 USD/10 ml compared to US pricing of 0.80~2 USD) while it taking +30 days to deliver outside of europe for more economical price
    • found one for 99 CZK/5 USD that id usable after search of 4 people -> still very difficult to get one
  • intended to be designed on demand for the specified use
  • Full repair of #86 that has been overheated which caused the mask to bubble off and expose the tracks.
  • Making mistakes such as #86 more idiot-proof to avoid overheating the PCB

Relevant: The solder mask is pressumably a photopolymer (https://en.wikipedia.org/wiki/Photopolymer)