Latest Example…Steel Bike frame, Beadblasted and blown off.. Rinsed with HOT WATER… I then pretreat with Columbias’ Iron Phosphate using a spray bottle.. Doing this outside with a HOT water hose handy to rinse off the parts… Kinda windy that day so the parts were drying fast..I kept it moist with the phosphate alot…then after the few minutes I rinsed immediatley with hot TAP water… As the wind was drying it I could see yellow film forming in sporadic areas.. I used compressed clean air to blow dry completly = however this yellow film was persistent…
The Tap water is softend..Country water/farm area but NO rotten egg smell..etc..
… Film almost appears to be hard water stain in nature… When dry – I used a white cloth and some of it wiped off onto it….
I have done steel clutch covers and no staining…Not a windy day so the parts had adequate time to Phosphate..etc..
Any ideas…??