Advice on Desoldering an IC

[Ethan O'Toole]

> I am trying to remove an IC from my PDP 11/24 CPU, a DS8641. I am really
> struggling to desolder it. I am using the technique of applying fresh solder
> and then removing it. But after multiple cycles of this I think I am
> starting to damage the PCB.
> Are there any tips for removing ICs?
> Thanks
> Rob

I use a Hakko 808 and have found cases where the pin size of the IC is 
close to the hole size, and then you can't get the solder out.

Some tricks I have used include Chip quick. This is a different allow you 
"solder in" with existing solder. It has a lower melting point so stays 
liquid longer. It's great for SMD and troublesome through hole, but you 
have to clean it off and that part sucks.

If you can get some of the legs loose on the chip and then apply some 
pressure to pull up chip and heat the troublesome pins, but be careful 
not to lift traces. This sometimes allows chip to "walk" up

Flux also helps sometimes

Hot air is another trick but probably left to modern boards.



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: Ethan O'Toole