Advice on Desoldering an IC

[Antonio Carlini]

On 15/04/2022 18:49, Rob Jarratt via cctalk wrote:
> 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.

I have that one too and I've found it to be reasonably good (compared to 
a manual pump - I've never had access to an expensive desoldering station.).


I've not tried it on anything Qbus related, only relatively modern 
motherboards and the like, but it has been quite good at getting the 
solder out. Sometimes I need to wiggle the end of the pins to break 
contact with the via. Removing a 20-pin IC can take a good 15 minutes 
but when the IC legs don't stick then it can be very quick. I have 
sometimes resorted to using a hot air gun with the fine nozzle to warm 
things up first and then use the Duratool.


When I first got the desolder gun I played around with scrap 
motherboards to get the hang of it.


There are a fair few YT videos about that Duratool (it seems to be a 
variant of the ZD-915) and there are various modifications that people 
have made. Those videos often have examples of it in action along with 
hints and tips that people have found useful. As usual, take with a 
hefty grain of salt. (The ones that modify the tool to try and increase 
the vacuum pressure seem particularly sketchy ... YMMV).


Antonio


-- 
Antonio Carlini
antonio at acarlini.com