How To - learning new techniques
Hello all! So there have been a few times when someone knows what they want to do, but may be lacking the abilities or knowledge on how to do it.
I thought it would be a good idea to create a new page for this - Mostly I have a feeling that there will be linking to some videos. If a picture is worth 1000 words, what is 30fps worth?
First up on the list is something I personally do when reballing larger BGA - This one is of an iPhone 7 CPU. If you get the techniques used here, SMC is NO PROBLEMO.
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The important things to note are - I am applying pressure in the centerish of the stencil. Not worried about the solder paste below the tweezers as it will flow. But this will stop your stencil from bowing/lifting in the center. I like to use 385c by 40 air on my Quick. Find a setting that works for you. This is what I like. It is not a rule or a solution.
2nd up... Is your solder paste too dry or wet? Here is me being an foolish man, and refreshing my solder paste. It dried out to a clump and well, its what I had near by. Is your paste too dry or wet? This is what I do to thin out my paste some.
If you want it to be thicker. I will drag it across my black mat a few times to let the flux stick to the mat, but take the balls with my scraper. I don't use paper towel or stuff like that.
3rd up, is how I reball SMCs. The Quick and dirty way. This is the rest of that above video.
I adopted this method after reballing about 50 macbook air RAM ICs from some other experiments. As the key to everything - Practice makes better.