Thank you, Ken, i will try that.
I am a, i admit it, sucker for Youtube ads. I saw this one for a rust remover:

https://www.pipiup.com/funnel/checkout-powerful-rust-remover-for-metal-and-stainless-steel

but i want to be careful with anything “too strong”, plus i am – at last – skeptical about Youtube ads.

-Hue Miller