On Mon, 13 May 2002, Tal Bejerano - AMC wrote: >folding transparency sheet look to me not to accurate, can >anyone suggest other better ways? Take a scrap of copper clad PCB material and make an L shaped piece with 3" X 4" long legs about 3/4" wide. In other words, shaped like a carpenter's square. Tape one transparency to both arms. Flip the whole thing over and very carefully line up the other transparency. Tape one edge only - to the longer arm. The tape is your hinge. I like to leave about 1/4" of border around all sides of the PCB. Be sure to place the transparencies such that you leave at least some border - don't try to position the edges of the finished board right at the edge of the L shaped holder. Tuck your sensitized board into the pocket formed by the transparencies and holder. Put it into the exposure frame and expose. The reason for taping one transparency to only the long arm is to allow for easy removal of the exposed PCB. After exposure, the photo-sensitive laminate sticks to the transparencies. But since the one transparency is taped on 1 edge only, you can peel it away from the PCB without damaging either and without changing the registration. I've been making double sided boards this way since the mid 70's. It works and its easy! dwayne Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax Celebrating 18 years of Engineering Innovation (1984 - 2002) .-. .-. .-. .-. .-. .-. .-. .-. .-. .- `-' `-' `-' `-' `-' `-' `-' `-' `-' Do NOT send unsolicited commercial email to this email address. This message neither grants consent to receive unsolicited commercial email nor is intended to solicit commercial email. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.