Q. How do I restore a large garden shears that has totally rusted shut?

[LuckyCharms]

14. This is what you want:

https://www.harborfreight.com/1-gallon-evapo-rust-rust-remover-96431.html?gQT=1

Get a large, flat plan. Pour this product in the pan. Drop in the shears. let them soak. Removes rust down to the bare metal.

This stuff works. No solvents or other toxic material. Will not harm any components. Can dispose of down the drain. Or, pour used liquid back into the jug, and it can be re-used later.

Dry off the shears, apply some WD-40, and you're good to go.

Final edit: This stuff is about $28.00 a gallon, but since it is re-usable, it will eventually pay for itself. If you have other rusty tools, drop them in the pan along with the shears.