Originally Posted by shine
i have no problem with phosphoric acid . i have used it since the early 70's . but when i switched to epoxy things changed .some cars i blast do not need it others do . i still use it but have to be diligent on how i use it . since the chemistry police are lurking we cant say neutralize any more so i will say rinse thoroughly while still wet . this will avoid any problems with the epoxy . the epoxy will still stick if not rinsed but only at about 60% and a possibility of other problems.
i have started using milkstone since a dairy friend here turned me onto it . the milkstone is 54% phosphoric acid where ospho ,navel jelly and such are around 15-30 % .so it will be cheaper once mixed with water or on bad rust used straight it will work a little better. the stuff the paint mfg sell is weak usually around 5%. good only for cleaning.
and a word of caution , paint mfg are in the business to sell you things whether you need it or not. the last place to seek advice is with a paint rep. follow tech advice but be cautious on product recommendations .
and the only thing you can convert rust to is a different color of rust .
never heard of milkstone ,whats it used for in the dairy biz?