Electronics Forum | Tue Jul 02 15:50:28 EDT 2002 | blnorman
FIrst, be a doubting Thomas and never trust supplier propaganda sheets, do your own testing. How often do you knead the paste? We have a standing requirement that if the paste printer is idle for 30 minutes, we have a minimum of 4 kneads before pri
Electronics Forum | Wed Dec 09 09:47:32 EST 2009 | dyoungquist
I am curious as to why you need to mix.... We use a 500g cartridge with air gun. Our process is remove the cartridge from the fridge, allow it to warm up to room temperature before inserting into air gun, then apply bead of paste to the stencil. N
Electronics Forum | Wed Feb 23 03:22:47 EST 2011 | pkannan
(Corrected the Subject line - sorry for Spelling ) You are very right. There are 2 major factors 1) There is going to be Flux separation. This is basically due to fact that metal particles are heavier than the Flux vehicle system, and due to gravity
Electronics Forum | Fri Feb 25 02:30:32 EST 2011 | pkannan
Dstadem, Thanks for bringing your in valuable experience with the J STD 005 " Requirements of Solder Paste". I fully agree with you that the Solder Paste can be qualified for shelf life by doing simple viscosity test and visual inspection for coal
Electronics Forum | Fri Nov 11 22:14:11 EST 2022 | kumarb
I would certainly test the boards but from our experience, the vacuum sealed in room temp, no issues at all with our PCBs sourced from Suntak / PCB Founder / Fastprint / Yaxinda / JLCPCB well past the 12 month mark. We building boards purchased 5-10
Electronics Forum | Tue Nov 15 22:33:16 EST 2022 | kumarb
Yes, solderbility. I recall one case of a vendor we met at a past HK electronic fair. Pricing was ok, we selected them and ordered a batch of boards. After a few months of leaving the PCBs in a sealed package (vacuum), we attempted to use the PCBs. W
Electronics Forum | Tue Feb 22 17:57:32 EST 2005 | Austinj
Most solder paste has a shelf life of 1 week at room temperature after opened, if resealed at the end of the shift/day. Most shelf lives are 4-6 months at 40F (refridgerated) or 1 month at room temp (unopened/sealed). Recommended stencil life is appr
Electronics Forum | Fri Jan 06 00:03:10 EST 2023 | SMTA-64419298
Hello Evtimov, sorry...just saw post as I was looking through list...a bit late. I don't know if you ever got your answer. IPC-4552A covers EniG finishes and suggested shelf life. I've referred to these doc's quite a bit. Good spec's ! Yes, I beli
Electronics Forum | Wed Feb 23 00:45:49 EST 2011 | tsvetan
Does someone with technical knowledge knows what exactly happend with the solder paste after the shelf life pass? What we have seen is sometimes flux separation which disapear after a good mix, and change of viscosity i.e. drying. The tin, silver and
Electronics Forum | Wed Jun 25 12:13:31 EDT 2003 | russ
A lot of it depends upon what the lead terminations are and the storage conditions. For example if they are tin you will run into trouble. We have used all types of parts that are all ages (We just started doing BGAs that are 5 years old.) I don't
