Hi Steve! Don't you just love Samtec connectors? Seems like they design a connector that looks good on paper, but more or less throw it over the wall when comes to manufacturing with it. We build some boards that use some Samtec connectors that are very similar, they're from the QTE series: http://www.samtec.com/ftppub/cpdf/QTE-XXX-XX-X-D-XXX-MKT.pdf These are a little longer than yours and I ran into the same issues...unsoldered pins. Here's a picture of the ones we put down: http://stevezeva.homestead.com/files/Samtec_QTE.jpg We put these on two assemblies, one has .062" thick PCB, the other has a .093". We have far more problems with the .062" thick board than we do with the thicker one...something to consider. I had the stencils re-made after we built the boards the first time because of the open solder joints. There's a bunch of 0402's on these boards so I'm using a .005" thick stencil. When I had the second stencil made, I had them open up the apertures for the connectors to 1-mil over in the X/Y dimension of the pads, And that seemed to help quite a bit. The overprint wicks back into the pad during reflow and gives a little more solder volume to help compensate for any coplanarity. One thing I can tell you is that these are a BEAR to rework! The thing that makes it tough is the grounding strip down the middle of the footprint. It can be done though. I have a Hakko FR-1012 IR preheater that I've had to use, and let me tell you I don't think I could have reworked one of these connectors without it. Steve -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Sauer, Steve (Xetron) Sent: Wednesday, April 09, 2008 1:24 PM To: [log in to unmask] Subject: [TN] Samtec QMSS-DP Series Differential Pair Connectors Good Afternoon, Does anyone have any experience with the subject connectors? I'm currently evaluating these connectors (the mate is QFSS series) for a new application and am experiencing issues with coplanarity of the leads resulting in random nonsoldered pins. The coplanarity is listed on the spec sheet as .004" (.10mm) max and I'm using a 6mil stencil with 1:1 apertures (as recommended by the mfr). Thanks in advance for your assistance. Steve Steve Sauer, CEPM Sr. Project Engineer Northrop Grumman Xetron Cincinnati, OH 513-881-3368 [log in to unmask] --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------