Homebrew PCBs

Mike,

I don't think anyone is too concerned about converting a printer for 
PCB work to also work for printing on paper.  So, as far as MISPRO 
inks printing ugly colors, no one cares for PCB work. It is only 
used as a resist, once etched, it has no further purpose.

I don't know for certain if MISPRO inks are required for the 
process.  In my early crude tests with yellow Epson ink, I had some 
promising results. Mind you that was not done with a printer so I 
have not taken it to that level just yet.

At some point this Winter, I hope to do some more work with an R220 
printer to work on this concept further.  With that printer I will 
be focusing on the Epson inks to see what can be done with them.  

Under-etching on thin traces is not the fault of the resist.  That's 
a function of the etching process.  You would get that same problem 
with toner transfer, photo-resists, etc.  I suspect spray etching 
system may work better to help reduce that problem.

Another advantage to the inkjet process is the precision which so 
far appears to be better than can be done with toner transfer.  
While this is generally not a big problem, if drilling on a CNC 
machine, it can add to the problems as you would need to scale your 
coordinates to get things to line up good. Not a huge problem, just 
one more thing in the process.

While I still favor toner transfer (because I can do it), I think 
the other processes have merrit too such as ink jet printing as well 
as isolation milling.  Once I get my CNC machine worked out, I will 
be trying a variety of methods including some hybrid methods by 
combining the various technologies.

The problem with toner transfer is that it is very hit-or-miss for 
many people, myself included.  One day I can make a perfect double 
sided board.  The next day I can't repeat the process using the 
exact same materials and such.  So, while it works fine for me most 
of the time, it's worth it to look for alternatives if for nothing 
else, something to do and learn about.

Chris