I picked-up almost all of my " Rough Iron " from my local " Swapmeet " .. I'm only doing a few " Pieces " on my small apartment Porch area. So, the " Ice Chest " stays outside, without any worries of " Toxic Fumes / Electrical Fires /Caustic Materials splashing in my Eyes, etc.. "
However, you will have to use approx " 2 Gals of Vinegar " per project , as it's useless after one use . And it does require lots of " Heavy Scrubbing " , & inspection, to decide how much more " Soaking Time " needed ..to remove/loosen/ soften, all of the Rust/Scale
An old 48 quart , plastic Ice Chest, with 50%Vinegar & 50%Water (after soaking Waffle Iron). There was a noticeable oily film on the surface. I would have thought, that all of the oil was completely Burnt off , in the " BBQ " ( 600 + deg.) ??
Now, " IF " I was doing more & had the space .. I would invest in the " Electro System "..
L.M.