I printed several stencils but they would not line up: it appears that my printer (HP MFP 1217nfw) expands in the Y direction significantly and in a non-uniform way.
To get good registration of the stencil, I had to print on 3 separate sheets of transparency film, keeping the design centered on the sheet (not at the top of the page, which would have allowed me to print two designs on the same sheet).
* Exposed 2 min 10 with 3 layers of stacked transparency film.
* Black stencil areas were overexposed, resulting in gunk remaining on the board. (Also, the developing solution was not new and possibly a bit weak).
* I did not do a hardening exposure after rinsing
* Bad result at etching with lots of copper remaining
* Also quite a few cut traces
Lessons learned:
* spend more time doing a very thorough lamination to avoid raised traces
* my printer deforms designs depending on their position on the page
* reduce exposure time for 3 layers of transparency (1 m 55?)
* rinse more carefully, scrub gently, watch for remaining gunk
* let the board air dry before touching up
* do a hardening exposure (also serving as a double check that there's no leftover resist)
* use fresh etching solution (2 parts H2O2 / 1 part HCl)
