We always waiver lack of topside fillet if the hole is heat sinked, our decisions are based on the last version of IPC-610 which has a picture for ACCEPTABLE fillet for this case. Being at home now, I don't remember the% of fillet height, but you can check it out. Gaby Hinners Hans Civ WRALC/LYPME wrote: > Hi Ya Steve, > > Yeah, we have a fairly thick (~140 mil) backplane with several leads heat > sinked to the nth degree. Fortunately, our customer had already been > through it once and waived the topside fillet requirement for those babies. > In fact, they said if we did see a good fillet in those locations we fried > the board someplace else. Talk about a process control indicator . . . > > Hans > > ~~~~~~~~~~~~~~~~~~~ > Hans M. Hinners > Materials Engineer (Process & Manufacturing) > Warner Robins Air Logistics Center > Avionics Production Division > Manufacturing Branch > 380 Second Street, Suite 104 > Building: 640, Mail Stop: LYPME > Robins AFB, GA 31098-1638 > Voice: (912) 926 - 1970 Fax: (912) 926 - 7164 > mailto:[log in to unmask] > http://www.robins.af.mil > > -----Original Message----- > From: Stephen R. Gregory [mailto:[log in to unmask]] > Sent: Thursday, August 10, 2000 2:00 PM > To: [log in to unmask] > Subject: [TN] Topside solder fillets after wave... > > Hi all! > > Been trying to dial a profile in on the wave today with a board that's > fairly > thick, probably around .090", polyimide, all PTH with a fair amount of the > IC's being ceramic. We use a spray fluxer and a RMA flux. > > The first boards have been coming off without the preferred topside fillets > at a number of locations. I've been playing with the pre-heat, belt speed, > and even did something that I don't like to do, which was to flux the > topside > of the board. > All to no avail...I still had quite a few places that didn't have topside > fillets, and that is something that doesn't go over well here at all. > > I started noticing that the places that didn't have topside fillets were at > the same locations. So I came back to my 'pooter and looked at the gerber > for > the board. What's really weird was that everyplace there's a thermal for a > pin is where I have no topside fillet??? I thought that thermals were > supposed to help prevent that from happening? But it's true, every single > place there is a thermal= no top solder. Has anybody ever seen that before? > > -Steve Gregory- > > ############################################################## > TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ############################################################## > > ############################################################## > TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ############################################################## ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################