N1 Fitting Machining Module 15 Milling Machine

N1 FITTING & MACHINING THEORY MALUTI TVET COLLEGE LECTURER : MT MPHAGO Downloaded from hlayiso.com ITEMOHELENG CAMPUS

MODULE 15 MILLING MACHINE LO : Describe the safety precautions when using a milling machine, identify and describe different parts of a milling machine and distinguish between plain and universal milling machine. Downloaded from hlayiso.com ITEMOHELENG CAMPUS

SAFETY PRECAUTIONS FOR MILLING MACHINE  Clean the milling machine after each work period.  Never use air hose to clean the shaving or chips.  Make sure that you are thoroughly familiar with the machine before you attempt to use it.  Wear proper clothing and approved safety goggles.  Stop the machine before making any adjustments or taking measurements.  Stop the machine before removing chips.  Never reach over, or near the rotating cutter.  Take care to prevent running the saddle, or work, into the column. Downloaded from hlayiso.com ITEMOHELENG CAMPUS

MILLING MACHINE MAIN PARTS  See the drawing below: Downloaded from hlayiso.com ITEMOHELENG CAMPUS

MILLING MACHINE PARTS The spindle  Is hollow and provides the drive to the arbour and cutters. Arbour  Is located and held by the taper in the spindle nose.  Two driving keys on the face of the spindle ensure a positive drive to the arbour.  The arbour drives and holds the cutters in their correct position.  It supports fits and clamps to the overarm.  Overarm provides support and correct alignment for the arbour.  The column supports and guides arbour.  Knee fits on the column and can be moved up and down by hand or automatically.  The base is the bottom of the machine and supports the column.  Universal head can be used to cut very short leads.  Table trips , trips the automatic feed at pre-set positions. Downloaded from hlayiso.com ITEMOHELENG CAMPUS

MILLING MACHINE PARTS Adjustable footstock  Supports the work-piece on the opposite side of the dividing head.  Can be adjusted in the vertical plane for taper work. Bracing Arms.  Is fitted to the overarm and knee of the machine to provide better support to the arbour and prevent vibration and chatter when making heavy cuts. Downloaded from hlayiso.com ITEMOHELENG CAMPUS

MILLING MACHINE USES, PLAIN AND UNIVERSAL MILLING MACHINES Uses:  To flat , profile or shape surfaces.  Can be used for drilling, slotting , grooving and boring.  It cuts gears.  It can be used to produce cams.  It can be adapted for vertical work. Plain milling machine:  Is used to produce work where it is important to make heavy cuts. Universal milling machine:  Can swing in both directions for helical milling.  The spindle can turn in both directions.  Special attachments enable a horizontal machine to change into a vertical machine and slotting machine. Downloaded from hlayiso.com ITEMOHELENG CAMPUS

SUMMARY  Safety precautions for milling machine.  Main parts of milling machine.  Milling machine parts.  Uses of milling machine.  Plain and Universal milling machines. Downloaded from hlayiso.com ITEMOHELENG CAMPUS

ASSESSMENT Activity 15 page 240 of the textbook supplied by the college. “ Fitting & machining theory N1 by PJ Koekemoer and R Cameron”. 1 to 3 . (Multiple choice). And 5 of the next set of questions. . PLEASE FEEL FREE TO CONTACT ME ON WHATTSHAP FOR ANY QUESTIONS THAT YOU MAY HAVE. MY WHATTSHAP NUMBER IS 073 215 7689 THANK YOU ALL Downloaded from hlayiso.com ITEMOHELENG CAMPUS