On 1/11/02 at 12:44 PM [EMAIL PROTECTED] wrote: >What equipment do you use to apply the etch-resist pattern to the >boards, etch them, and then bond them together? >Is it all very expensive for a hobbyist to produce one-off boards for >experiments & prototypes?
The real problem is the thru-hole plating, the chemistry is 'interesting' not to mention expensive. Apart from that, single or two layer non-plated can be made quite cheaply and VERY precisely. I used to do that a lot - and would still be doing it if only I could find a source of highly concentrated hydrogen perxide and not immediately be branded suspicios with terrorist overtones. You can get blank boards that have the photo-resist pre-applied. Film can be produced using drafting transparency and a laser printer. For very fine geometry boards 600DPI is a must and you have to experiment because passing the papaer through the printer changes the dimensions. Fortunately, most PCB design programs have the capability to enter correction factors. I have done hundreds of boards this way, some with tracks and spacings down to 8/1000" - more than good enough for even the smallest SMD components. Laminating could be a problem, but it is not insurmountable, especially for small boards. It is DIRTY though :-( Nasta
