Electronics Forum | Wed Aug 09 10:51:22 EDT 2017 | cbeneat
I have a question for the experts. After a panel is printed, how long is too long for the panel to sit prior to reflow? I understand each paste will be different, wondering if there is a general rule of thumb?
Electronics Forum | Thu Aug 10 11:32:34 EDT 2017 | dleeper
You could always take a scrap board, paste it, and let it sit out over night. Reflow it and then you should have a nice visual aid, covered in solder balls and grainy, irregularly shaped solder mounds.
Electronics Forum | Wed Aug 09 11:59:19 EDT 2017 | dleeper
As you already know, it depends on the paste. There isn't really a rule of thumb, but less time exposed it better. The issue is the flux exposure to the air and ambient conditions. The flux can evaporate or absorb moisture from the air. If the paste
Electronics Forum | Wed Aug 09 14:55:42 EDT 2017 | cbeneat
Trying to show documentation/expert opinion to an operator or 2 why it's important to not let a first piece, that they so diligently built for the next shift to let sit for an hour, why that's not a good idea...other than me telling them so. And tel
Electronics Forum | Wed Aug 09 12:34:54 EDT 2017 | jdengler
It also varies with the types of deposits. Small deposits of paste (as seen on fine pitch parts or small chips) seem to be more affected by exposure. Jerry
Electronics Forum | Tue Aug 15 07:27:03 EDT 2017 | emeto
Most important factor - temperature. Back in the days I worked for a place without AC, and summer time this paste couldn't make it for more than an hour. In controlled environment you will be safe for hours or even a shift.
Electronics Forum | Mon Aug 14 15:09:14 EDT 2017 | charliedci
In my experience, in a temperature/humidity controlled environment, 1 hour, no big deal. 4 hours still ok. Overnight your pushing the limits but will probably reflow without issues. Any longer, could be a problem. Again, a lot depend on type of past
Electronics Forum | Thu Nov 03 18:20:15 EST 2005 | JG
Dek 265 GS Problem: Machine abruptly turns off. It can be in the middle of a stroke or just sitting idle. After the machine turns off we have to let it sit for a few minutes (sometimes 20) in order for it to restart. Any suggestions? Thanks in adv
Electronics Forum | Fri Mar 04 00:46:36 EST 2011 | kemasta
Hi ScottE "Is this ball sitting on a via?" I am not sure is I answered your question correct, the ball is sit on the pad.
Electronics Forum | Mon Apr 02 09:42:51 EDT 2007 | chrissieneale
Quick question for anyone - With this whole pasting and waiting thing - i've found out that the board is pasted, it sits around for a bit, then the components get placed on it. Then i thought it went into the oven BUT, it doesn't. It sits for a few