Frequently Asked Questions
1. When using water miscible coolants, what causes residues to form in my machine interiors or on my parts?
There are several contributing factors to the build-up of these residues. Water quality, choice of coolant, tramp oils and other contaminants can all contribute to this build up. First and foremost, check your coolant concentration with your refractometer to ensure your mix ration is on point! Feel free to reach out to us with any specific questions or concerns.
2. Is there an effective way to clean off the residue build up in my machine?
SMF recommends our Command Clean HD Degreaser. This product does an excellent job of removing residues without the use for harmful chemicals. The Command Clean HD also limits adverse reactions with your coolant, which can occur with other cleaners and degreasers.
3. Is it true that cleaners will damage the coolant and cause it to fail prematurely?
Most cleaners and degreasers contain chemicals that can weaken the emulsifier, which ties up the water and oil. When this emulsifier fails, any water soluble coolant with an oil content will split/separate (oil from water). The coolant, at this point, MUST be removed and the sump recharged in order to avoid poor finish, odor, rust/corrosion, etc. The Command Clean HD Degreaser is the only cleaner that we recommend for cleaning a machine's interior.
4. Does water quality have much of an effect on how well a coolant will perform?
Water quality is extremely important in maintaining a healthy water miscible metalworking fluid. (see Cutting Tool Engineering's "Pure Water" article on our Technical Database page). Water quality can affect every aspect of your coolants performance, including: cleanliness, tool life, rust/corrosion protection, residues, sump life, foam, stain inhibition, and emulsion stability.
5. What is the best way to remove tramp oils from my sump?
SMF carries a wide variety of systems for tramp oil removal, from simple wheel skimmers to elaborate oil removal central systems. Our most popular skimming device is our Skimray 1500 C-Thru Oil Separator. These all can be found under the "Equipment" tab on our home page.
6. What is the best way to mix my water soluble coolant?
The use of a proportioner (Equipment tab) will ensure a thorough emulsion, offering the smallest oil droplet size for maximum wetting at the tool/workpiece interface. There are many styles of coolant proportioners, so reach out to us with your application and we'll help match you up with the best fit!
7. Do I need a refractometer?
Yes, yes, yes! A refactometer ensures you have the right concentration of coolant concentrate and water for all water miscible metalworking fluids. The old "See, Slip & Smell" method of determining coolant concentration cannot be used with the hi-tech MWF's we have today. Refractometers can be found under the "Equipment" tab on our home page. When using a refractometer, it is imperative that you know the "refractive index" or "refractive multiplier" of the product in use.
8. Why is my machine rusting?
There are many factors that can contribute to rust.
First and foremost, are you running the product at the right concentration (concentrate to water)? Contact your MWF provider for the correct pecentage or refractive index. Avoid adding straight water to your water soluble MWF and never make coolant additions over your table, fixtures, or workpiece.
Has the chemistry of the water miscible MWF been altered due to advertant or inadvertant use of ANY type of cleaner, solvent, rust preventative, or corrosive?
Due to the age of a water soluble MWF the "rust protectant" (RP) additive can weaken and the system should be drained and recharged fresh.
Has the coolant "split" (separation of the oil from the water)? If so the coolant must be drained and recharged.
The use of "hard water" will prematurely cause the additives in a water soluble MWF to fail prematurely. Use treated water, reverse osmosis or deionized (see Cutting Tool Engineering's "Pure Water" article on our technical page).
If your facility utilizes evaporative coolers, it is important that the air coming from these coolers be diverted from blowing into a machine.
Change the water miscible MWF that you are using. Ask your supplier of MWF's or call Star Metal Fluids for a suggestion of a MWF that will be more compatible with your water and application, or for any additional help you might need.
Q. Can I add chlorine bleach, Pine Sol or Boraxo to my coolant to keep it from stinking?
A. Never! These household products will change the chemistry of your water miscible MWF and can cause serious dermatitis issues for operators, serious machine and part corrosion, and destroy the coolant and it's chemical/physical properties. When a coolant is "stinking", contact your MWF provider to determine the "cause" of the odor issue and treat the coolant with those chemicals approved by the manufacturer. Sometimes, odor issues are NOT caused by biological means and can be easily remedied with the direction of a good MWF supplier.
9. What could cause staining on aluminum?
Inexpensive coolants often lack the necessary metal deactivators needed to insure a compatible environment for the machining of aluminum and other metals. Water quality can play a major factor in alumimun staining. A high percentage of tramp oils could cause staining. A galvanic reaction could also be taking place due to the many dissimilar metals being machined. Sludge and metals should be removed on a regular basis from sumps. When getting staining check these possible causes and correct, then drain and recharge with fresh coolant. Other materials that are sensitive to staining are copper, brass, and bronze. Call Star Metal Fluids for further help.
10. Why do some of my people have adverse skin reactions to water miscible MWF's?
First of all, EVERYONE's body chemistry is different. What might affect me, might not affect you. It is important, though, to find a MWF that is safe for operators. Just because the product is safe to use, there are several things to considered to maintain a safe and healthy MWF:
Use a refractometer to maintain the manufactures recommeded concentration (too rich will cause irritation of the skin, nose, throat and eyes).
Keep tramp oil levels to a minimum (less than 1%).
Keep cleaners and other harmful products from getting into your coolant, as these can change the pH of your water miscible MWF. If you feel your coolant has become contaminated with with a foreign substance, best practice is to drain and recharge.
Has the emulsion been lost due to poor water quality? If so drain and recharge using a purified water.
Has an accumilation of dissimilar metals built up in your sump? The leaching of these metals will change the chemistry of the coolant. Clean the sludge and metals from the sump. Drain and recharge if necessary.
