couple of questions, jamesdart said his batch lost its strength after three days,anybody else had this problem? would putting in a sealed container help? i know my 22 dollar a gallon of evapo-rust did, reused three times.good for bolts, anything larger would cost a fortune. would heating up the mixture help(floating tank heater)we use one for the horse tank. as far as the cost, use the good stuff for delicate parts, the vinegar for the other, a no-brainer.