Hopefully someone here has a bit of experience with Dynamask dry film solder masks. I attached images below containing my last 2 attempts at using this stuff. My basic process is as follows,
1) manually tin etched board using my typical solder (MG Chem)+ lots of Amtech 559 flux
2) clean with alcohol
3) clean with alcohol + scuff pad
4) clean with powder based dishwashing detergent until water cleanly “sheets” off the surface
5) dry with clean paper towels
6) run through Amazon Basics laminator on higher heat setting (I always use a clean sheet of paper folded in half with the board in the middle for all steps)
7) V1 –
A) place clean board in a container with clean distilled water
B) cut Dynamask to size
C) remove 1 side cover
D) apply exposed side to submerged board
E) use credit card to squeegee out most water
F) remove board from water
G) squeegee out any remaining water (thoroughly)
V2-
A) remove 1 side cover
B) apply exposed side to dry board
C) use credit card to squeegee out any remaining air (thoroughly)
run board inside folded paper through laminater twice
9) apply bicycle chain oil to protected side of dynamask
10) apply transparency toner side down
11) squeegee out all oil/air leaving the transparency/image tight against the film
12) expose in direct sunlight for 5 seconds (tested and established as my best fine line resolution)
13) remove outer protective film and develop in 1 liter of microwave warmed distilled water (@~32C) with 4 grams of dissolved sodium carbonate (not bicarbonate)
14) develop until masked bits are clean
15) rinse in tap water
16) pat dry with paper towel
17) leave board in direct sun for 5 to 10 minutes to fully cure the dynamask
The problem with the spots/deformations seen in the pictures are visible after step 12. I can not see them after laminating the film to the board. However I am in a dark room and can’t see very well at this stage. I thought I was trapping water under the mask with V1, but I have a similar issue with V2 and a dry application. Any suggestions?
