Despite what the ads suggest WD-40 is NOT a lube, it is a solvent; a
very very light oil.

It would be better to use it as the solvent to clean the chain.

Thanks for the confirmation. This was the reason why I didn't buy
WD-40 when I was in Home Depot on that day.

I have seen people who keep a bucket of sand with some old oil mixed in
for garden tools. Things like shovels can be stuck in there a couple of
time and the sand cleans them and the oil prevents future rust.

Yes, I also saw this being done in a gardening TV show "Gardening by
the Yards". I choose not to do this because I don't have any more
bucket. I have used up all the drywall compound buckets from my last
home improvement project for various purposes (fishing, car wash,
....). I will have to make do with the "paper towel" approach. Thanks
for the suggestion though.

Jay Chan