Have the baking soda bath ready for the parts, the minute you take the parts out of the acid.

If you try to neutralize the acid directly you will require a lot more soda and have to buy new acid for the next batch. But it could be done, just not cost effective and messy when the soda started to foam.

R.

But the real problem, as alluded to above, is that this is not a harmless way to remove rust. Acid does not stop with the rust, it keeps on going. Acid-dipping body parts was not done to derust them, but to thin them. It was a way to make a lightweight part, by "chemical milling" much of the metal off the part.