Hi Dick - I have a split opinion - for the SEMCO type tube container, since the solder paste has minimum exposure to the factory environment, I would be minimally concern on not utilizing over night refrigeration, especially if you are consuming the solder paste in a couple of days. I would consider jars a different story since they allow for a far greater exposure to the environment. The safe option is to refrigerate over night. One way to decide is to select a product that has good yields and run a test - build for 3 weeks with and without refrigeration. Look at the product yield/defect data after the 6 weeks and see if you can statistically tell a difference in the two populations. Depending on how you fast you consume solder paste and the factory conditions, it may not be necessary to refrigerate over night. The solder paste formulations used today are much more robust to factory environmental conditions that solder pastes supplied 10 years ago. Dave From: "Richard D. Krug" <[log in to unmask]> To: "[log in to unmask]" <[log in to unmask]>, TechNet E-Mail Forum <[log in to unmask]> Date: 03/13/2013 11:23 AM Subject: RE: [TN] Cooling of Solder Paste Overnight Both. I have more concerns with the proposed when it is a jar that has been opened, then closed with some quantity of ?room air?. Dick Krug, CSSBB, CSMTPE Senior Process Engineer Sparton Complex Systems 30167 Power Line Road Brooksville, FL 34602-8299 p (352) 540-4012 (Internal Ext. 2012) [log in to unmask] From: [log in to unmask] [mailto:[log in to unmask]] Sent: Wednesday, March 13, 2013 12:04 PM To: TechNet E-Mail Forum; Richard D. Krug Subject: Re: [TN] Cooling of Solder Paste Overnight Hi Dick - what is the solder paste container: a SEMCO type tube or a jar? Dave Hillman Rockwell Collins [log in to unmask] From: "Richard D. Krug" <[log in to unmask]> To: <[log in to unmask]> Date: 03/13/2013 07:42 AM Subject: [TN] Cooling of Solder Paste Overnight Sent by: TechNet <[log in to unmask]> It has been proposed that we take left over solder paste and store at ~60 F overnight to extend life and integrity of paste. This would be paste in its original tube or jar, not recovered from a stencil. We are located in Florida. During the summer, when the AC is reduced overnight, temperature in the building gets to ~85 F. Has anyone done this? What are the pro's and con's? Dick Krug, CSSBB, CSMTPE Senior Process Engineer Sparton Complex Systems 30167 Power Line Road Brooksville, FL 34602-8299 p (352) 540-4012 (Internal Ext. 2012) [log in to unmask] ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________