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Q. When using a soluble oil what causes the brown residue I sometimes get in my machine interiors? 
A. 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. 

Q. Is there an effective way to clean off the brown residue build up in my machine? 
A. SMF carries the Command Clean HD Degreaser. This product does an excellent job of removing this brown residue without the use for harmful chemicals. 

Q. Is it true that cleaners will damage the coolant and cause it to fail prematurely? 
A. 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 (oil from water). The coolant at this point MUST be removed the the sump recharged. The Command Clean HD Degreaser is the only cleaner that we recommend for cleaning a machine's interior. 

Q. Does water quality have much of an effect on how well a coolant will perform? 
A. Water quality is extremely important in the maintaining a healthy water soluble metalworking fluid. (see Cutting Tool Engineering's "Pure Water" article on our technical page). 

Q. What is the best way to remove tramp oils from my sump? 
A. SMF carries a wide variety of systems for tramp removal. From simple wheel skimmers, belt skimmers, stand along skimer/aerators, portable skimming devices to central coolant processing systems. These all can be found under the "Equipment & Water Treatment" tab on our home page. 

Q. What is the best way to mix my water soluble coolant? 
A. The use of a proportioner (Equipment & Water Treatment tab) will ensure a thorough emulsion offering the smallest oil droplet size for maximum wetting at the tool/workpiece interface. 

Q. Do I need a refractometer? 
A. Refactometer ensure you have the right concentration of concentrate and water for all water soluble metalworking fluids. The old "See, Slip & Smell" way of determining if a coolant has the right mix cannot be used with the hi-tech MWF's we have today. Refractometers can be found under the "Equipment & Water Treatment" tab on our home page. 

Q. Why is my machine rusting? 
A. There are many factors that can contribute to rust. 
  1. Do you have the right concentration (concentrate to water)? Contact your MWF provider for the correct pecentage or refractive index. 
  2. avoid adding straight water to your water soluble MWF and never make coolant additions over your table, fixtures or workpiece. 
  3. Has the chemistry of the water soluble MWF been altered due to advertant or inadvertant use of ANY type of cleaner, solvent, rust preventative, or corrosive? 
  4. 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. 
  5. Has the coolant "split" (separation of the oil from the water)? If so the coolant must be drained and recharged. 
  6. 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). 
  7. If you facility used evaporative coolers it is important that the air coming from these coolers be deverted from blowing into a machine. 
  8. Change the water soluble 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 to 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 soluble MWF and can cause serious dermitis issues for operators, serious machine and part corrosion and destroy the coolant and it's 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. Some times odor issues are NOT caused by biological means and can be easily remedied with the direction of a good MWF supplier.  

Q. What could cause the staining on aluminum? 
A. Inexpensive coolants often lack the necessary metal deactivators to insure a compatible environment for the machining of aluminum and other metals. 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. Call Star Metal Fluids for further help. 

Q. Why do some of my people have adverse reactions to water soluble MWF's on their skin? 
A. First of all...everyone's body chemistry is different. What might affect me won't 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. 
  1. Use a refractometer to keep the manufactures recommeded concentration (too rich will cause irritation of the skin, nose, throat and eyes) 
  2. Keep tramp oil levels to a minimum (less than 1%). 
  3. Keep cleaners and other harmful products from getting into your coolant (these will change the ph of your water soluble MWF). If so drain and recharge. 
  4. 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 y our 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.