Desoldering H@ll

[olliethebasset]

Good morning folks. I am having one heck of a time recapping my a500 board (rev 6). I don’t know if my equipment is at fault or if it’s solder on this thing. I have a good setup with a Hakku soldering iron and a vacuum pump. The vacuum seems to be working okay and my iron is great. I’ve never had this problem before but this is the second Amiga board that is resistant to desoldering. Any tips? I have added fresh solder to the points, no luck. I have used flux, no luck. I have turned everything to a very high temperature, no luck. If anyone has a tip they would share, I’d appreciate it. I don’t want to butcher this board attempting to recap it.

 

[HomeLate]

What brand of desoldering gun (pump) are you using and at what temperature?

Use low temp solder (like Chipquick low temp bismuth) to reflow the joints and then use your desoldering gun. Remove as much solder you can. If the capacitor is still stuck, use a soldering iron to heat the capacitor pin, one by one and genlty pull the capacitor, one leg at a time. Start with the positive (square via) and then the negative via.

Whatever you do, don't pull the capacitor out with force or you'll remove or damage the via.

If you decide to use low temp solder, be sure to remove everything after the capacitor is removed with solder wick. Low temp solder is very brittle.

 

[olliethebasset]

Thank you for the response. I have a feeling that my gun might not be up to the task. I’ll try cleaning it. I bought it on Amazon and it has worked in the past when I’ve desoldered Mac boards, but maybe not anymore.

How would I heat the legs of the capacitor if it sits flush with the board?

 

[HomeLate]

Heat up the via and the remaining solder. The remaining solder should melt and you should be able to gently remove the pin/capacitor. Which Hakko do you have? I'm using a JBC with a barrel type solder point which is designed for thru hole soldering. I don't know if these exist for Hakko. The barrel type solder points sit around the pin and also make contact with the via.

Amiga 500's have large ground planes which suck up the heat. It's even worse if mainboards like Atari have a thick PCB. In that case I preheat the board. Do you have a ZD-series desoldering station perhaps? These are not bad, but do not perform well on thick layered mainboards and mainboards with large ground planes. I have a Hakko desoldering station but these are expensive. I work on electronics as a side job so for me it was worth the money.