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CPU replaced - but not finished

A project log for 68040 upgrade for Powerbook 520c

Unsoldering and resoldering a 180-pin QFP! Thrills! Excitement! A full 68040 in a Powerbook 520c!

hackadayhackaday 01/29/2016 at 20:500 Comments

I got the new CPU soldered on. I had planned on soldering each lead with my finest tip, but this proved impractical. Also, the fine tip really doesn't supply enough heat if you need to clean up with solder wick, which I did occasionally. I switched to my standard tip and ran it along the ends of the pins while touching it occasionally with very fine solder.

At this point most of the pins look good. A few are dry, as I can move then with the tip of my SMT tweezers. I'll be bringing over to someone with a microscope this weekend so we can touch up the pins properly.

So far, I'd say this has been pretty challenging to solder. I'd considered really flooding the pins with solder and cleaning up with fluxed solder braid, but it's really tight in there and even with pre-fluxed wick, I found it didn't do a particularly reliable job of soaking up all the excess solder.

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