If the clinch, or solder fillet formed on the lead, violates minimum electrical spacing it is a defect. The short story is that the space needs to be more than .13mm for applications with less than 100 volts between the lead and the conductor when the assembly is coated as you have described. Assuming a PTH, the lead clinch should be partial, only enough to retain the component during handling prior to soldering (between 15°and 45°). The lead clinch should not extend beyond the diameter of the anular ring around the hole. The PTH diameter must be specified to allow the assembly process to meet these requirements. The PTH diameter should be between 0.2mm and 0.7mm greater than the lead diameter. The closer to 0.2mm the less trouble with clinch and the more trouble with auto insertion. Some designs create problems by using very small rings and placing non-common conductors in close proximity to the undersized rings. In the old days, only a few years back, I specified dry film solder mask on board desings that had such compromises. That may not be possible today, dry film photo imagable mask is not popular and most fabricators are not maintaining the equipment needed to apply the mask. Wish I could be more help. > -----Original Message----- > From: TechNet [mailto:[log in to unmask]]On Behalf Of [log in to unmask] > Sent: Monday, May 20, 2002 5:36 PM > To: [log in to unmask] > Subject: [TN] assembly spacing > > > I have a component lead that is clinched on the bottom and the > lead is almost > touching the surface of a conductor. Good old 001C says that the > oreintation > of the clinch relative to any conductor is optional. However, it appears > that direction is causing the problem. Of course the assembly is > conformal > coated and it is nearly impossible to determine the exact spacing from the > surface. > > Are there other guidelines for this condition? > > Thanks for any info > Susan Mansilla > Robisan Lab > > --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------