On Tue, 28 Feb 2012, dave wrote: > Date: Tue, 28 Feb 2012 22:04:50 -0800 > From: dave <dengv...@charter.net> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: emc-users@lists.sourceforge.net > Subject: Re: [Emc-users] Film Emulsion for Encoder Wheels? > > On Tue, 28 Feb 2012 20:06:25 -0600 > Jon Elson <el...@pico-systems.com> wrote: > >> dave wrote: >>> If anyone is really desperate I think I still have some KPR (Kodak >>> photoresist) around. IIRC ... vacuum pull down the photomask over >>> the substrate (board) expose with UV. Develop with toluene. Etch. >>> >>> Since I'm a packrat (I'm obviously relate to Neotoma cinerea ) ;-) >>> the KPR is tucked away someplace. It may have auto-polemerized. >>> >> Arrgh! Horrible stuff, horrible chemistry, terrible exposure control >> and repeatability. >> Use dry film resist, all aqueous processing with mild chemicals. >> Vastly better >> exposure control (I've used both, as you might tell from the above) >> visible results after development so you know if the resist >> expose/develop step went well before you try etching. Think and >> Tinker sells it in small quantities, I >> believe. >> >> Jon > > 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. > > 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. > > 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. > > Dave
I used KPR many years ago and it worked perfectly (not too surprising as it was good enough for wafer masks. In fact I think the bottle I had came from Fairchild Semi's surplus store). It had extremely sharp line defnition and excellent development characteristics. I simply dipped bare cards in the KPR, baked in the oven, contact printed (sunlight!) with litho film I had exposed in a Speed Graphic 4x5 camera with a copy machine lense. At this point the KPR make a color change from greenish where unexposed to purplish where exposed. Then I developed in the Xylene Toluene mix, no problems at all. This is by no means a suggestion that anyone run out and buy some carcinogenic solvents and play with them in their kitchen (as I did) >> >> ------------------------------------------------------------------------------ >> 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 > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ 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
