On Wed, 29 Feb 2012 12:19:39 -0600 Jon Elson <el...@pico-systems.com> wrote:
> dave wrote: > > > > > > Sorry you had such bad luck with it. I diluted it IIRC 1:1 with > > toluene, floated in on the copper, drained off any that would run > > off, let it dry, exposed it with a very intense UV lamp. Developed > > with toluene and then etched. Never had one fail. > > > I bought the GC variety in a spray bottle, it was supposed to be just > re-branded > KPR. > > The UV lamp was the nasty part of it (about 1 KW); we used it to > > convert diethylstibesterol to a colored compound that could be > > measured in a spectrophotometer; not something one usually has > > laying around. > I used everything from photographic halogen floods to mercury vapor > lamps, just needed a longer exposure. When developed, you could > barely see the resist, and it was very easily scratched. > > Aqueous based chemicals are probably a safer way for most people to > > go. I did this a LONG time ago and was not aware of any > > alternatives. > Dry Film resist is the industry standard, DuPont Riston brand, used > in huge quantities > at professional board houses. I mostly use the dry film for solder > stencils, now, but > it works for PC boards and other types of engraving, etching, > manufacturing of > all sorts of thin parts with apertures, grilles, etc. > It is dyed deep blue, so you can really SEE the developed result > before etching. > I occasionally touch up pinholes, presumably from dust when exposing. > > Jon > The dry film resist sounds like an easy way to go. Photoresist just has to be the way to go for encoders. I suspect one could even silver glass like mirrors used to be made; if is darkens over time that might just help the contrast. Only real problem is that the silver layer is pretty fragile. Dave > ------------------------------------------------------------------------------ > Virtualization & Cloud Management Using Capacity Planning > Cloud computing makes use of virtualization - but cloud computing > also focuses on allowing computing to be delivered as a service. > http://www.accelacomm.com/jaw/sfnl/114/51521223/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
