Heat and Noise from a Haas Spindle
Haas ties a spindle temperature over 140 °F (60 °C) to a spindle lubrication system that does not work correctly. Too little oil, too much oil, or the wrong oil at the spindle bearings can overheat the spindle. Haas calls for SHC 625 spindle lubrication oil and correct air pressure to the spindle.
An unusual spindle noise sends Haas technicians to the spindle drive belt, the encoder pulleys and belt, and the spindle lube pump. Rubbing noise and heat at the front cap can mean a bumped spindle cartridge pushed the cap to one side. Haas checks that cap with a piece of 0.001 in. shimstock all the way around.
Haas Spindle Repair Shops
Machine Tool Science
Gaffney, SC
Brands: DMG Mori, Fanuc, Haas, Mazak, Okuma
Motor City Spindle Repair
Dearborn, MI
Brands: DMG Mori, Fanuc, Haas, Makino, Mazak, Okuma
Checks Before the Spindle Comes Out
Haas asks for a Spindle Inspection Report Checklist before any spindle parts get replaced. A seized spindle starts with a review of the alarm history for signs of a crash. Damaged spindle bearings call for a test with a vibration analyzer.
Tool runout should not exceed 0.0003 in. (0.076 mm) with a dial indicator on the tool and the spindle turned by hand. A drawbar force gauge in the spindle measures clamp force against the Haas reference table. Damaged Belleville spring washers in the drawbar can let a toolholder fret in the taper.
Problems That Look Like a Bad Spindle
Chatter and vibration can come from a tool or toolholder that is too long for the job. Haas notes that a 10 percent reduction in the length-to-diameter ratio raises tool stiffness by 25 percent. Tool stick-out from the holder should stay under 3 times the tool diameter unless the job requires more.
Tools that stick in the spindle can trace to a tool left in the spindle for hours while the machine sat idle. Low air volume to the machine, a dry pull stud, and the wrong drawbar force cause the same problem. Coolants with paraffin waxes can stick tools when high-pressure through-spindle coolant runs with small orifice tooling.