PCBs

[Hcabnivek]

In a message dated 98-03-22 19:28:10 EST, you write:

> 
>  What do people think about "iron-on" PCB resists?
>  The description I saw in Mouser said that there was no chemicals involved. 
> How
>  then do you etch away the copper?

Well, that's no chemicals involved in getting the resist onto the copper clad.
You still have to etch as usual.  They mean no photochemicals etc. are needed.
As for how it works, if you have a good laser printer with good quality toner,
and you except that you will probably waste a whole sheet of the stuff on
practice and screwups, and you don't mind having to (probably) re-enforce some
of the traces with a resist pen, then it could be said to work quite well.
Whenever I produce a board this way I always reflow solder over all traces and
pads after cleanup to make certian that no "micro-cracks" in the iron on
resist were etched through, leaving an undetectable void in a trace.
If I had to producea few of some small (3x6 in.) board, then I'd give this
system an A-/B+,  and one of the standard photoresist processes about a C-.
If I had to produce say 20 boards, or a full sized (8x10 in.) board then I'd
give the photo process the A and I'd likely fail the toner transfer systems.
Just my 2 pennies.  Your results may vary.
Kevin