Peter, a "supported hole" is one that is "plated through" with a metallic material, usually copper followed by tin/lead or such. An unsupported hole is one that contains no plating or other metallic material. Usually supported holes (plated-through-holes [PTH]) have connecting circuitry on both sides of the board, where as, unsupported holes may have one connecting circuit or even none. I hope that clarifies it for you. IPC-A-610C figures 6-4 and 6-27 show examples of plated through (supported) holes. Figures 5-11 and 5-13 show examples of non-plated though (unsupported) holes. Ron Dieselberg Trainer/Auditor CMC ELECTRONICS CINCINNATI [log in to unmask] -----Original Message----- From: Peter Lee [mailto:[log in to unmask]] Sent: Tuesday, June 25, 2002 15:22 PM To: [log in to unmask] Subject: [TN] Definition of Suported/ unsupported hole Technet, Can anyone explain the difference between a supported and unsupported hole on PCB? I am reading a section on IPC-A-600 RevF and section 2.10.3/4 specify difference acceptance criteria according to the hole type. Rgds, Peter ---------------------------------------------------------------------------- ----- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------- -----