For those who like to try new things. I tried the toner release paper mentioned by Roger and although it worked reasonably well after I got the ironing temperature and technique down I was a bit bothered by the cost. Recently I tried the backing sheet for Avery Laser Printer Labels and guess what ... it worked, IMHO, as well as the blue stuff and was much cheaper. At 09:00 AM 5/20/99 -0400, you wrote: >>>> X-Mozilla-Status2: 00000000 Message-ID: Date: Wed, 19 May 1999 10:15:15 -0400 From: Roger Morella X-Mailer: Mozilla 4.51 [en] (Win98; I) X-Accept-Language: en MIME-Version: 1.0 To: Lawrence Lile Subject: [OT] Best PC Board Etching Resist Method (was: hp7475 PC board plotting) References: Content-Type: multipart/alternative; boundary="------------BA21757E20F19C42E4C043A0" If you have a laser printer and want a quick and easy etching resist method, contact Techniks, Inc. in Ringoes, NJ. <www.techniks.com (908-788-8249)< We have been using their PnP-Blue Pres and Peal iron on printed circuit board transfer film for a couple of years and have have found it to be the best method so far (and we have tried a lot of methods ) This is an iron on method where you print the board to their transfer film and iron the film onto the surface of the PC board using an ordinary household iron (if your wife won't let you use 'her' iron you can buy one at the local thrift store for about $5). The result is 2 layers of resist. The film layer and the toner layer. The combination provides a very high degree of resist which will work very well with fine traces and small holes. The hardest part of the whole process is cleaning the toner off the board after it has been etched (which confirms the integrity of the toner as an etchant resist). They can be reached at <www.techniks.com or call them at 908-788-8249 The price we paid was $30 for 20 sheets of 8 1/2 by 11 An excellent deal considering the time and frustration we have saved. Roger Morella <<<<<<<< Daniel F. Welch Director Research and Development American Scientific Associates Email: amersci@flash.net