Plugs are cheap, but it is also very easy to clean them

I keep a brass wire brush on one of my bench grinders. It just takes a few seconds to clean a plug.

On trips, I have to burn 100LL like every one else, so I usually change oil and filters every 25 hours. I keep an extra set of cleaned plugs so when I change oil, I put the cleaned plugs in, and take the dirty ones home to wire brush and check the gap.

Seem a shame to throw away good plugs just cause they are dirty.

Rodney