Re: Coating older metal queen excluders with light food grade oil while in storage
It's my understanding that naval jelly and similar materials (phosphoric acid-based) will convert the iron oxides to less-crumbly iron phosphates, arresting the rust process. Then coat with anything of interest, such as beeswax. You might find that a gallon or a few of appropriate and appropriately diluted material in a flat tray sized to hold/immerse an excluder would do well for your needs. Set the excluders to the side to dry, then possibly spray any particularly vulnerable areas with a spray galvanizing paint. Just a suggestion.
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"I thought I made a mistake once, but I was wrong." (heard often from the late David Sebree) Still making them, myself