Sticking lock

I had a desk day, processing data from site on Friday. The only fresh air was a brief walk in the field first thing.
Early evening, I fixed this door catch which had been getting progressively more difficult to operate. It needed a complete strip down. They accumulate a lot of black dust over the years which I think is wear from the mechanism. I "borrowed" some of Mrs SJR's  WD40 - which I gave her for her last birthday- and this worked wonders.
Its working fine again.
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