circuitnet
Sponsor
Essegi Automation
Scaling SMT Traceability
High-mix electronics manufacturing requires precise material control. This whitepaper explains how Tecnimaster improved traceability, inventory accuracy and picking efficiency through integrated automated storage and reel-level tracking.
Essegi Automation
Quick-Turn PCB Assemly
Sponsor
AIM Solder
Viscosity Does Not Equal Rheology: What Solder Paste Measurements Really Tell You
Viscosity is a useful solder paste quality control measurement, but rheology provides a more complete understanding of how paste will roll, fill, release, recover, and remain stable during stencil printing.
AIM Solder
Ask the Experts
QUESTIONS
  
SUBMIT
  
MEMBERS
  
JOIN
August 31, 2011 - Updated
August 28, 2011 - Originally Posted

Re-qualifying Cored Wire Solder

Is there a process for re-qualifying cored wire solder that has passed the expiration date?
P. G.
Expert Panel Responses
Always a tricky one, in theory there is nothing in the solder wire that can go off so the expiration date could be just a logistic function. How ever depending on the field you are working in it could be possible to see if it is still useable, in some industries you will have to abide by the use by date. If you can use material then a quick easy test is to see how it solders to a flat copper strip or coupon. Make sure the copper is clear of oxide by using a mild acid wash or abrasive clean. The wash in alcohol to make sure it is clean and free of oils. Put a known weight or length of the wire screwed up into a ball on the copper and heat it up. This is best done on a solder bath (float and a static part of a wave solder machine) or hot plate, but any controlled heating method will do. If the solder spreads out giving a uniform and relatively flat silver circle then the wire is probably OK. If it form a lump or ball then it is probably not so good

Richard Boyle
Richard Boyle
Global Product Champion, Henkel Electronics
Richard Boyle is a Global Product Champion at Henkel Electronics. He has over 25 years experience in the electronics assembly industry and is responsible for the global technical service of all of Henkel's solder materials.
Submit A Comment
Comments are reviewed prior to posting. You must include your full name to have your comments posted. We will not post your email address.

Your Name


Your Company
Your E-mail


Your Country
Your Comments



Free Newsletter Subscription
Circuitnet is built for professionals who bear the responsibility of looking ahead, imagining the future, and preparing for it.

Insert Your Email Address

Sponsor
SCHUNK
Gripping Systems from micro assembly to heavy lifting
The first industrial-suited grippers from SCHUNK were a milestone. Since then we have brought countless newly and further developments to market.
SCHUNK
Ultrasonic Stencil and Pallet Cleaner