Sparking MagSafe port no longer works

So a while back I noticed my MagSafe plug would spark when being connected or disconnected from the MacBook. Sometimes the spark would immediately switch the MacBook off and I'd sometimes lose what I was working on but most of the time it was just a worrisome spark. I cleaned up the connectors but it had no effect on the sparks or immediate shut downs. I went through forums and deduced that it was probably the MagSafe board acting up. Being frugal and confident in my repair skills I bought a board online, along with a new charger, and set to work.

Everything went fine but the sparks returned.

As before I tried unplugging the charger from the mains (3pin and other) before disconnecting the MagSafe and switching off the MacBook etc but that didn't stop accidental disconnections and the issues I was previously having continued.

A couple of weeks ago and my MacBook stopped charging again. With the last few percent of battery I powered down the computer I bought a new board from ifixit and successfully installed it and got the battery to a full charge.

I made the mistake of disconnecting the MagSafe to charge my wife's MacBook. I saw a spark and my MacBook wouldn't charge up again.

With the last few percent I powered down the otherwise working computer to look for a solution.

So now I have a working computer that won't charge. I don't know if the board has failed again so I guess I'm looking for help to solve this once and for all.

Any ideas?