Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hi guys,

I tried my first photo process board this weekend and the process
failed completely. I am using the dry film, negative resist from MG
chemicals.

The failure was in the developing of the resist. While developing,
all the resist washed off. It was developed as I could see the
traces in the resist, but faintly.

The developer solution was a best guess on dilution so this is
probably my main failure point.

I am wondering what actually holds the resist to the board though.
Per the instructions, I am suppose to peel off the backing, apply
resist to the board and then run it through a laminator twice. Is
this what causes the dry film to stick to the board or is it the
exposure process?

I also suspect that using vellum for the artwork is not a good
thing. Using some scraps, I noticed that exposure is much different
using transparncy than vellum. So my next attempt will be using
transparencies and to carefully measure the developer.

Chris