Homebrew PCBs

mikegw20 wrote:

>Anything that cuts down on drilling is good by me.  I do double sided 
>smt with some vias made with a bit of copper wire if space is tight.  
>If you are feeling cheeky you could just put big pads in and solder 
>your jumpers to them without the hole.  
>
>In my opinion drilling is the worst bit of diy as it is the one job 
>that gains no/minimal efficiency the more boards you make.  Everything 
>else like etching and cleaning gets more efficient if you do batches of 
>boards.
>
>Additionally I have found that double sided smt is easier to design 
>that double sided through hole as you are not forever dodging pads.
>
>Mike
>  
>
  Second on everything said, it is the way to go.  You can do a whole 
lot even just single sided SMT with less jumpers than you'd think once 
you get used to that kind of layout..  When you need double sided, take 
connections out to the edge of the board above one another, and just 
solder a wire around the edge of the board, no drilling involved.  Need 
a bus, just take 8 or 10 out over the other 8 or 10. and have an extra 
piece with the 8 or 10 parallel tracks.  Cut straight along that edge, 
hold up your extra piece, and run a solder ball down both sides to make 
the top to bottom connection.  Easier than doing 1 or 2 seperate vias.  
Or space at .1", and use header pins or similar for the top to bottom 
join.  Lots more ways to do many connections across the edges with no 
drilling once you start doing it a bit more too. 

  And not going through hole does help a great deal.  I've redone most 
of the Eagle TTL chips as SMT pads, and just solder them to the top of 
the board.  Adds a lot to your useable space when you can route whatever 
you need on the other side without pin interference.  Almost no parts 
really need to go through the board for normal use.  Still nice to have 
a driller but I use it more for mechanical stuff than drilling boards now.

Alan