Hi All, A technique I've seen used to get into the inner layers of a ML board uses a dentist's drill. The bit spins at around 400,000RPM on compressed air bearings and the tungsten tip gives absolute and total control. I saw a technician excavate his way into the centre layers of an 8 layer board using an ordinary illuminated bench magnifier for precision, and the result almost blew me away. I had a go at it myself, and the degree of control is astounding. I guess just as well - you would want your dentist to have absolute control, right? By the time he'd finished his repair, I was hard pressed to find the point of entry as the cut had minimal width and no extraneous damage. -- Cheers .......Andy K. ======================================================================= Andy Kowalewski Phone: +61 3 9264 3767 PCB Design Engineer Fax: +61 3 9264 3507 NEC Australia email [log in to unmask] Mobile: Australia 0412 281 284 International +61 412 281 284 ======================================================================= ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################