Advice on Desoldering an IC

[Jay Logue]

As mentioned, I find it best to cut the pins off the IC right at the IC 
body and then remove them individually.  Once the IC is removed, I use a 
third hand to hold the board vertically, and then grab each pin with 
tweezers or needle-nose pliers from one side of the board and lightly 
touch the soldering iron to the hole on the other side until the pin 
pulls free.

Once all the pins have been removed its fairly easy to clear the solder 
using a solder sucker.  Hold the solder sucker on one side of the hole, 
stick the a fine-tipped soldering iron into the hole from the other 
side, and then release the solder sucker.  Its a bit of a balancing act, 
but it works pretty well and introduces minimal heat into the board.

Replaced a good 20+ chips across my various PDP-11 boards this way.

--Jay

On 4/15/2022 10:49 AM, Rob Jarratt via cctalk wrote:
> 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.
>
>   
>
> I am using a fairly cheap desoldering station (this one
> https://cpc.farnell.com/duratool/d00672/desoldering-station-uk-eu-plug/dp/SD
> 01384?st=duratool%20desoldering). Its spec in terms of vacuum pressure is
> equivalent to that of the professional Hakko ones though. I am also trying a
> hand desoldering pump. None of these are able to clear many of the holes of
> solder, although some are doing better than others. Nevertheless, the IC
> remains stubbornly unmoving.
>
>   
>
> Are there any tips for removing ICs?
>
>   
>
> Thanks
>
>   
>
> Rob
>