> > I made a really great looking toner transfer. When I etched it in
a spray
> > tank (standard chemicals not FeCl) several traces got slowly
sprayed
> > away. It seemed as if the traces might have been weekly bonded
and the
> > spray just washed them away over 1 or 2 minutes. Is this usual?
> > John
>
>
> i assume you have cleaned the board well?
>
> maybe the mechanical force from spraying is too much for the toner.
> what are the "standard chemicals" exactly?
>
> did you use a iron or a laminator?
> which printer model/ toner manufacturer did you use?
Good questions; I'll add a few more:
Board cleaning is probably the biggest buggabo; sometimes you can get
good adjacent toner bonding and mask over a small fingerprint smudge
or some other contamination.
What temperature are your "standard chemicals" etching at? The
combination of heat and spray pressure might be too high for a weakly
bonded toner resist. (If the board is cleaned properly the TT bonds
are generally pretty good --also a bit of work getting off after
etching!)
How fine are the traces that are disappearing?
What oz. clad are you using? Although I haven't had much
undercutting using 1 oz - .5 oz and a FeCl agitated bath; even with 8-
10mil traces (if you are watching it closely!).
I haven't seen the need for this with the laminator, but some have
suggested "cooking" the newly formed resist layer for a bit in an
oven to allow the toner reflow and bond better to the board.
If you are using a laminator and cut the board down to size before
etching; did you clean/sand the scored edges? These can lead to
local eruptions along the cut edge and create just enough of a valley
on the board that the image will get uneven pressure through the
laminator.