In addition to their machining performance characteristics, the Mobilmet 420 Series fluids are multi-purpose in nature which helps reduce the problems associated with cross-contamination, thus improving production and reducing rejects. They are formulated using chlorine-free additives reducing the environmental impact of disposal and spillage. The Mobilmet 420 Series fluids control built-up edge and protect the tool tip from wear. They provide improved surface finish that may eliminate the need for finish turning or forming before grinding.

Features and potential benefits of Mobilmet 420 products include:

Features Advantages and Potential Benefits
Excellent machining performance Increased production resulting from longer tool life and reduced downtime for tool changes and wheel dressing
Improved surface finish and dimensional accuracy resulting in fewer rejects and better quality finished products
Helps increase feed rates and machine speeds
Suitable for a wide range of ferrous and non-ferrous metals and machining operations Fewer cutting oils required, potential for reduced inventory costs
Multi-service capability Eliminates cross-contamination problems and provides further inventory benefits
Light, transparent color Provides a clear view of the work area at all times


Mobilmet 420 Series fluids are recommended for a wide range of machining operations on all types of metals. They can be used as multi-purpose oils when a common fluid is required for machine tool lubrication and as a hydraulic fluid assuming proper viscosity selection.

  • Mobilmet 423 and Mobilmet 424 are recommended for machining aluminum, magnesium and copper, brasses and bronzes and, in addition, are recommended for steels and cast irons having a Brinell hardness up to 200. They can be used for severe cutting operations of difficult-to-machine non-ferrous alloys such as silicon-copper, silicon-bronze and copper-nickel. They are very effective lubricants for the machine tool lubrication system under a wide range of temperature conditions
  • Mobilmet 426 and Mobilmet 427 are recommended for critical machining of non-ferrous metals and automatic operations on materials having a Brinell hardness up to about 300

Typical Properties

Mobilmet 420 Series 423 424 426 427
Viscosity, ASTM D 445
cSt @ 40º C 15 23 32 46
cSt @ 100º C 3.5 4.9 5.7 6.9
Pour Point, ºC, ASTM D 97 -15 -15 -15 -12
Flash Point, ºC, ASTM D 92 182 200 210 212
Specific Gravity @15º C kg/l, ASTM D 1298 0.859 0.862 0.874 0.877
Copper Strip Corrosion, ASTM D 130, 3 hrs @ 100º C 1B (max) 1B (max) 1B (max) 1B (max)


There are no reviews for this item. Write Review


Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 2 questions Browse 2 questions and 2 answers
Why did you choose this?
The Lubricant Store Store
Was recommended by a fellow machinist
Chris E on Jun 27, 2019
Was recommended by a fellow machinist
Chris E on Jun 27, 2019
how does it do on 316 stainless steel?
John F on Aug 17, 2018
BEST ANSWER: To give you a definite answer I would need to know what you're doing with the 316 stainless steel. According to Mobil Tech, the MobilMet 426 does pretty well with most products, however, they do not recommend honing, drilling deal holes or broaching with this product. It is not an aggressive oil but they feel it will do well on 316 stainless steel.