Homebrew PCBs

yes, that is exactly how I do it.  Alignment is critical.  some 
things I've found that help:

I use full 8.5x11 sheets for each side - it makes it easier.  Since 
my paper costs me a penny a sheet I dont care if I waste a little.

It helps to have a tracing light box and a Scotch (I think) double 
sided tape applicator.  The paper I use is fairly translucent. I use 
an old slide sorter for the light box.  Its a pain to use but allows 
pretty accurate alignment.  A window on a sunny day does pretty well, 
too.  Temp tape the bottom paper to the glass and tweak the top until 
you are there.  Holding the two pieces of paper up to a lightbulb can 
work but its much harder (for me anyway).  I like to have a flat 
surface to work on.  a light box is pretty easy to build, by the way -
 I plan on doing so, someday (hah, FLW).

The tape applicator allows one handed application of the double sided 
tape so once you have your alignment, a quick swipe and you've got 
your tape in place.

I try to tape as far away from the board image as possible to 
minimize the effect of differential paper lengths from the tape to 
the board.

vias make great registration points - if I can see light through the 
hole, I know I'm pretty close. pay close attention vert and horiz 
alignment.  The good news is that you can be up 10 mils off and still 
have a usable board.

I start ironing in the middle of the board as that is the best chance 
of evening out the distortion caused by the differential paper 
lengths.

Once I started using the ink jet paper, it took me about 4 tries to 
finally get it.  I bought a bunch of cheap, thin double sided boards 
from goldmine and practiced.  dont be afraid to wash off the toner 
and start again. acetone strips toner almost instantly.

One final point.  Its often the case that if you tweak your design 
around a bit, you can get to a single sided board.  this is always 
more desirable than double.  at least from a simplifying production 
basis.  I'll often change pin assignments on my MCUs to reduce 
complexity.  pin-swap is a good thing too.  

Good luck.  

Phil

--- In Homebrew_PCBs@yahoogroups.com, "joshdewinter" 
<joshdewinter@y...> wrote:
> > I'm very pleased with the results for both 1 and 2 sided boards.
> 
> Hi.  I'm trying to perfect my double-sided boards.  How do you make 
> your double sided boards?  Do you line them up, tape them together, 
> insert the board in between and iron them at the same time?
> 
> -Josh