The part of them we can see look okay. Can you see anything on the heel?
Strong backlite and look down the lenght of the connector. If you got a heel
fillet I'd say your home free.

Guy Ramsey
Senior Lab Technician / Instructor


E-Mail: [log in to unmask]
Ph: (610) 362-1200 x107
Fax: (610) 362-1290


  -----Original Message-----
  From: TechNet [mailto:[log in to unmask]]On Behalf Of Stephen R. Gregory
  Sent: Thursday, October 11, 2001 2:52 PM
  To: [log in to unmask]
  Subject: [TN] SAMTEC surface mount sockets...


  Hi All!!

  We've got this little board we're building here, and it plugs into another
board via a set of surface mount headers and surface mount socket from
SAMTEC...their CLP-SM series is what I think they're called.

  Anywho, the leads on these babies are stamped from phosphor bronze that is
pre-plated with tin. When the leads were stamped out they have a '"Burr-up"
cut on the sides of the leads, and a "Burr-down" on the toe of the leads.
After reflow, they really don't good that good. Check out some pictures:

  http://www.stevezeva.homestead.com/

  This is class-3 stuff, and the J-STD's says this is acceptable, to wit:

  J-STD-001 addresses this as acceptable at page 19 of the standard:

  9.2.6.1 Flat, Ribbon, "L", and Gull Wing Leads - Joints formed to flat,
ribbon, "L" and
  gull wing shaped leads of either stiff or flexible materials must meet
alignment and
  solder fillet requirements requirements of Table 9-2 and Figure 9-4 for
each product
  classification. Leads not having wettable sides or ends by design (such as
leads
  stamped or sheared from pre-plated stock) are not required to have side or
end
  fillets. For devices where the lead length (L) is shorter than the lead
width (W), the
  minimum side joint length (D) shall be 0.75 L.

  I just want some other opinions. The solder appears to wet fine under the
foot and back at the heel...and depending on how much plating has smeared up
or down from being stamped out, I MAY see a little bit of side filleting
about half the thickness of the lead, and I MAY see somewhat of a toe
fillet...but most of the time the solder looks as you see it in the pictures
I posted...

  Thanks!

  -Steve Gregory-