Electronics Forum | Fri Apr 21 09:03:59 EDT 2006 | choppy
I guess the first thing to look at is the temperature. We had to heat more for QFP256 on sample boards and we saw discoloration on some small parts. Just try to sense around when profiling to see what's there.
Electronics Forum | Wed Dec 19 14:20:19 EST 2007 | slthomas
I'm inclined to suggest that you use a specified temperature, thus eliminating your situation. Why not use 90�C? I suppose you could calculate a duration for 70 based on the requirements at 40 and 90 if you really wanted to, but still I wonder why.
Electronics Forum | Wed Jan 13 12:33:15 EST 2016 | trampacorp
Baking it's key for success on this task. Water evaporates @ 100 deg. C. Use that temperature, or higher, for that process and your problems or concerns can be taken care of. Be wise on your cleaning process, otherwise this could lead to failures too
Electronics Forum | Tue Feb 20 15:39:31 EST 2001 | fmonette
To my knowledge, the 40C was established as the maximum "safe temperature" for all tape and reel packaging. The actual specs may vary somewhat for different types of reel, pocket-tape, cover-tape but you must be concerned with the cover tape adhesive
Electronics Forum | Tue Mar 09 12:13:27 EST 2004 | Gabriele
I want just to confirm what Dave suggested you. J-STD-033a, par 6. Boards Rework tells you plenty of useful informations. 6.1 Component removal, RWK and remount 6.1.1 Removal for Failure Analysi 6.1.2 Removal & Remount 6.2 Baking of Populated Boar
Electronics Forum | Tue Feb 20 04:18:39 EST 2001 | chinaman
Hi everyone if once the exposure time is exceeded the only option is to bake the components. I learned there is an "old spec" for the baking conditions (24h/125C or 192h/40C) and a "new spec" which is the current standard specifying conditions of 4
Electronics Forum | Tue Apr 23 18:34:45 EDT 2002 | mkallen
My first posting was not very clear -- sorry. Let me try again. What I want to know is: can I eliminate the drying (baking) process completely IF I know that the good parts (i.e., those not being reworked) are going to stay under some threshold tem
Electronics Forum | Mon Jun 28 10:02:06 EDT 2004 | fmonette
The answer is yes, it is possibly a moisture-related problem. You can confirm this by baking your parts at 125C for 48 hours (ref. J-STD-033A, table 4-1). For more technical background on this issue I recommend you read the following paper : Impac
Electronics Forum | Mon Sep 12 20:24:26 EDT 2022 | stephendo
I'll answer the easy part. If you put low temperature trays in the oven at 120C, they will warp and partially melt. I have seen it more often with reels of LEDs. Someone is told to bake them before use so the put them in the batch oven and the next
Electronics Forum | Thu May 06 18:31:29 EDT 2004 | Dreamsniper
"Polymide Films absorb a great deal of moisture. Polymide laminates must be baked at more than 1 hour at 100'C or better for a double sided PWB prior to exposing the laminate to elevated temperatures such as that required for soldering. Moisture abso