🚀 go-pugleaf

TO: news@synapse.bms.com

Rich,

-> 1) Can I realistically make double sided PC boards?  My first board
-> will be single-sided, but I would like to try more complicated boards
-> later.
->
-> 2) What are the best photo-resist methods and chemicals?  I have seen
-> ads for both positive and negative photo resist.  Is there any
-> difference other than
-> the need for negative vs. positive artwork?

Double-sided boards (homebrew) can be a pain since it is almost
impossible to produce plated through holes (PTH). There is a vendor
which has a PTH kit, but it is expensive and time-consuming. Also,
alignment of the component and solder sides is critical. With patience,
a non-PTH DS board is feasible, however.

I've heard (on this newsgroup and in Don Lancaster's column in Nuts&
Volts) that negative photo resist works much better - more forgiving of
exposure variables and it is more stable in the development phase.

I'm moderately experienced with home fabrication of PCBs, but the more I
look at it, the more attractive a PCB house looks. I've come across a
Canadian vendor (AP circuits) that will produce two 4x5" board, DS/PTH,
for about $79 total. The per board price goes down as total area
increases. You have to consider your time, so outsourcing may be worth
it.

My main problem with home fabrication is getting the negative - does
anyone have a fast/cheap way of getting a high quality negative on film
? (SMT features)

Chris