Electronics Forum | Wed May 09 17:13:06 EDT 2007 | zanolli
Re: 63/37 paste reflow Is there a standard reccomended time (ball park) above liquidus? What are the negative ramifications if the TAL is too short or too long? Thanks in advance
Electronics Forum | Thu May 10 08:09:52 EDT 2007 | davef
There is no standard for time above liquidus. It is described rather broadly by the solder paste supplier. Reflow Zone: If the temperature is too high, boards may char or burn. If the temperature is too low, cold and grainy solder joints will resul
Electronics Forum | Fri May 25 13:38:15 EDT 2007 | mfgengr
TAL Too Long - dull solder joints, dewetting. TAL Too Short - cold solder, insufficient wetting. You want TAL to be as short as possible (but not lower than 30 seconds), but long enough for every solder joint to be above TAL for at least 30 seconds.
Electronics Forum | Fri Nov 30 06:16:25 EST 2007 | aj
Hi all, What do most of you aim for when profiling BGAs ? Currently I aim for time above 60 or 70 secs but I read a report that 40 secs would be more suitable. Also peak temp - I aim for 240-245 but again this report stated 230-235. any input app
Electronics Forum | Mon May 28 09:37:02 EDT 2007 | davef
Look here: http://www.aimsolder.com/techarticles/Time%20Above%20Liquidus.pdf We have no relationship, nor receive benefit from the company referenced above.
Electronics Forum | Thu May 10 08:05:22 EDT 2007 | pjc
30 to 90 seconds TAL is typical.
Electronics Forum | Fri May 18 12:09:20 EDT 2007 | ed_faranda
I have been TAL around 45 to 90 seconds. I prefer the longer TAL so, I set my profiles around 80 seconds. In the old days (Before RoSH), the longer times would help with wetting. But, since Lead-Free, well. We all know the story about wetting now
Electronics Forum | Fri Dec 16 11:04:23 EST 2005 | chunks
Over all time will be dictated by your conveyor speed. Your conveyor speed will be dictated by your products time above liquidous. Time above liquidous is dictated by the manufacturers specification. Time and temp before reflow will have to be ach
Electronics Forum | Fri Jun 22 03:11:53 EDT 2007 | vlazern
Our Heller oven is functioning well. However, we see defects from the oven, such as shifted coil inductor components, and missing chip components from time to time. When we re-scan the board at the AOI, the defect was not present at that stage,hence
Electronics Forum | Mon Jun 25 19:36:36 EDT 2007 | bga_kid
If you calculate CFM using the numbers you have provided you are pulling 1396CFM out of the oven. I am not sure what Hellers spec is but I know a Speedline OmniExcel Air machine should be set at 300CFM. I do know for a fact that to much exhaust can s
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