Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "rmustakos" > I'm about to try 
some TT stuff.  I'm not ready to etch, yet, but I
> want to play with TT some to get the transfer right.  I printed out 
a
> design with 6 mil lines and spacing using an HP1200, and it looks
> great on paper (like so many other things <G>).  Do the lines widen
> when you transfer?  Or is there something with the etching that 
limits
> the minimum width?

I'd probably try something on the order of 10-12mil at first --those 
are fairly easy.  6mil is doable, but will take a bit of practice.  I 
try to avoid anything under 8mil trace/ 6mil clearance, simply 
because (1)my printer is 600dpi and I get aliasing below that (2) 
without a solder mask it's pretty easy to damage a 6mil trace when 
soldering (although with hot air, you can get away with quite a 
bit).  That said your 1200 dpi should give you better results; but 
I'd suggest you try some looser tolerances until you've done a few.

As a side, has anyone done any homebrew pcb/ bga placement?  TT or 
not.