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John Stockman
¿ªÔÆÌåÓýThank you all, I will plan to do it all in one session. Solder paste is new to me.
John Stockman, KC2THY
Sent from my Verizon Wireless 4G LTE DROID
Jean-Paul Louis wrote: Cecil,
You¡¯re playing with fire when you wait for reflow,
The solder paste is VERY sensitive to moisture, and the flux evaporate fairly fast.
So, you end up with crusty paste that might hold the parts a bit, but you are
almost certain to create cold solder joints, and tons of solder balls.
At all the places I have worked, 6 hours was the shelf life of a board with solder paste and parts.
Past that time, the PCB was washed and recycled because it was the most expensive part.
The paste and the inexpensive parts were trashed. Some (very few) very expensive ICs were recycled.
I understand the hobbyist viewpoint, but please don¡¯t suggest that it is an acceptable practice.
I would suggest to place a few parts and reflow them, then you can wait, then add fresh solder paste, place parts
and reflow those.
Too many reflows are not good for ICs, but 3 to 4 is OK.
So you can limit the number of reflows by adding heat screens on your board for the parts already soldered
(aluminum foil makes a good screen)
My $0.02
Jean-Paul (AC9GH)
On Apr 17, 2014, at 11:03 PM, Cecil Bayona <cbayona@...> wrote:
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