The two locks on my front door were becoming very difficult to operate and sometimes the key would become stuck inside the keyhole. I was ready to go buy new locks, but then I remembered how my grandfather would use graphite powder as a dry lubricant for delicate pocket watches.
I took pictures of the lubrication process and wrote up a guide. The total cost for the lubricant was about $5 ordered online.
Here's the guide -
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The locks work great now and require very little effort to operate.Cheers, Paul Michaels Ft. Lauderdale, FL