3 worn out keris

[apolaki]

Hello!

I bought regular vinegar jug at store. It says "diluted with water to 5% acidity"

How many cups should I add and how much vinegar should I pour afterwards for this bath for the rusted keris?

I am assuming I shouldn't just submerge the keris in straight vinegar even though it says already "diluted with water to 5% acidity."

Thanks again!