Ten mil lines work fine. When you etch fast you have to keep a close eye on the board or you can undercut the runs. Adjusting the temperature and etchant flow allows me to make the etch time a bit longer, but with a "gentler" touch on those thin runs. If you find you are getting jaggedy edges or pinholes, check the resist pattern BEFORE etching. Many times the problem is not at the etching end, but at the resist end. If there is a pinhole the etcher will just naturally eat away at it! CLEANLINESS of the board before and after the resist is applied is crucial to successful etching of really thin traces. Fr. Tom McGahee ----- Original Message ----- From: Mitchell D. Miller To: Sent: Monday, July 17, 2000 3:19 PM Subject: Re: [EE]: PCBs using toner transfer paper > > My current method of etching ... > > P.S. How fine can you make your traces and how much isolation do you use? > Using the upside-down-cake (er, board) method with Ferric Cloride, I've done > 16 mil traces with 14 mil isloation with great success. On my last board, I > had drawn a single line about 10 mils, but there were several spots where > the etchant undercut it pretty bad. Not sure why, but this one trace is > much worse than the others. I've been creating my board with precoated, > positive acting boards (from MG Chemicals) and a laser printed image on a > transparency. > > -- Mitch > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]: PIC only [EE]: engineering [OT]: off topic [AD]: advertisements -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]: PIC only [EE]: engineering [OT]: off topic [AD]: advertisements