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Coolant residue sticky/rusty


Aug 24, 2009
Western PA
We have never had a problem until recently with coolant residue sticking to our CNC VMC tables and rusting. The coolant tanks are 200-300 gallons and we use a semi-synthetic. Even scotchbrite and the stone won't remove the sticky droplets whether dry or wet. We switched coolant brands, same issue. We called the water company and they use chloramines instead of chlorine to disinfect and that residue is corrosive to metals. We see a suggestion to use potassium metabisulfite to neutralize the chloramine residue in the water as we add it to the tank. Anyone have experience or thoughts?
Have your water tested by the coolant company.
The droplets could also be from way oil/grease, not the coolant at all.
Filter you water DI.
If it is a chemical issue RO/DI
And possibly a charcoal filter, usually not needed though.

First is identify the issue, call coolant company for tests.
Take some fresh coolant mixed where it needs to be and wet the surface you want to be cleaned. Then wipe it all off 10 mns later. Nothing takes up old coolant like new coolant. Works for a sticky floor too.
Our coolant supplied cleaner is actually based on the coolant itself , just stronger with more emulsifiers and soaps 🤣
In those I cant get the shit off situations, where nothing works, I have used Blue Magic metal polish.(micro abrasive)
What has changed recently? Do you saw your own stock or use a service? Coolant residue on the stock from a services funky coolant was one companies coolant problems.
Yes, the liquid coolant itself will almost always take any dried coolant residue right off. I used to soak down the big HBM tables and let it soak just like mentioned above at the end of every day. Give it 5 minutes and wipe it all right off with a rag.