U cutter offset techniques N I T ADVANCED TECHNIQUES UNIT 7-1

Transcription

1 U cutter offset techniques N I T 7 ADVANCED TECHNIQUES UNIT 7-1

2 OBJECTIVES At the end of this unit you will be able to: Use trigonometry techniques to create cutter offset toolpaths for right angle, acute angle, and obtuse angle geometry requirements. Create cutter offset toolpaths for circular geometry requirements. DISCUSSION To mill a workpiece to size, you must program a toolpath that will maintain the center of the cutter at an offset distance equal to the cutter radius. Machining a straight line surface is easily seen in the illustration below. To change the direction of a cutter toolpath you must program the tool to stop at a location where it will be tangent to both the last surface that was machined and the next surface that you want to machine. The illustration at the right shows a change in direction to machine a right angle at the corner. The same procedure will be used for other angles: ACUTE ANGLES This will require a toolpath for an angle less than 90 degrees. UNIT 7-2 ADVANCED TECHNIQUES

3 The cutter radius offset is calculated by using trigonometry procedures. The steps are: þ þ þ þ þ extend the surfaces to clearly see the cutter placement. place the cutter in a location that will establish 2 points of tangency. draw a line from the center of the cutter to the point of tangency to form a 90 degree angle. draw a line from the center of the cutter to the intersection of the surfaces to be machined. calculate the offset. This illustration shows the required toolpath for an acute angle. The first step will be to extend both surfaces long enough to show the tool placement when it is tangent to both lines. Position the cutter so that it is tangent to both surfaces. ADVANCED TECHNIQUES UNIT 7-3

4 Create a line from the center of the cutter to the point of tangency. This length represents the cutter radius and will form a right angle with the extension line. Create a line that will connect the center of the cutter to the point of interface between each of the required surfaces. This will complete a right triangle and allow the X component offset to be calculated and added to the drawing dimension. Y COMPONENT (CUTTER RADIUS) X COMPONENT UNIT 7-4 ADVANCED TECHNIQUES

5 OBTUSE ANGLES This will require a toolpath for an angle greater than 90 degrees. The steps to setup the toolpath are the same as those for the acute angle. þ þ þ þ þ þ use extension lines. place cutter tangent to both lines. connect the cutter center to the tangent point (radius). connect the cutter center to the surface intersection. calculate the X component offset. add the offset to the drawing dimension. Y COMPONENT (CUTTER RADIUS) X COMPONENT ADVANCED TECHNIQUES UNIT 7-5

6 INSIDE TOOLPATHS The only difference between inside and outside calculations is the way the x offset is used. For external toolpaths the offset is added to the drawing dimension for internal toolpaths the offfset is subtracted. IMPORTANT: A radius will be the result of a cutting action. This radius will be determined by the diameter of the finish cutter. ACUTE ANGLE X COMPONENT Y COMPONENT (CUTTER RADIUS) OBTUSE ANGLE RESULTING CORNER Y COMPONENT (CUTTER RADIUS) RESULTING CORNER X COMPONENT UNIT 7-6 ADVANCED TECHNIQUES

7 UNIT ACTIVITIES Unless otherwise noted the programs will be written using the Bridgeport Boss 8-9 Format. Cutter diameters are your choice but you should change them occasionally to experience various situations. The following steps apply to all of the exercises: þ þ þ þ þ þ Complete all calculations. Complete the markup worksheet. Write the programs using the Cutter Radius Offset method. Use programmable offsets to center the workpiece on the machine table. Test programs at the machine. Save files as MA601, MA602, etc. Machine Activity 601: Haas Use MA201 1" Diameter End Mill Outside Frame Absolute Positioning Climb Milling Machine Activity 602: Fanuc Use MA202 1/2" Diameter End Mill Outside Frame Incremental Positioning Climb Milling Machine Activity 603: Fanuc Use MA203 1/8" Diameter End Mill Inside Frame Absolute Positioning Climb Milling Machine Activity 605: Haas Use MA301 Absolute Positioning 1" Diameter End Mill Outside Frame Climb Milling 1/4" Diameter End Mill Inside Frame Climb Milling Machine Activity 606: Fanuc Use MA302 1/4" Diameter End Mill Outside Frame Incremental Positioning Climb Milling Machine Activity 604: Haas Use MA 204 3/4" End Mill Inside Frame Absolute Positioning Conventional Milling ADVANCED TECHNIQUES UNIT 7-7

8 NOTES UNIT 7-8 ADVANCED TECHNIQUES

9 ADVANCED TECHNIQUES UNIT 7-9 P ro gram m in g A M A 201

10 CALCULATIONS UNIT 7-10 ADVANCED TECHNIQUES

11 PROGRAMMER: JOB: MA601 MACHINE: DATE: PAGE: LOCATION NUMBER X Y LOCATION NUMBER X Y LOCATION NUMBER X Y NOTES: ADVANCED TECHNIQUES UNIT 7-11

12 NOTES UNIT 7-12 ADVANCED TECHNIQUES

13 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MA601 MACHINE: DATE: PAG E: INSTRUCTION ADVANCED TECHNIQUES UNIT 7-13

14 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MACHINE: DATE: PAG E: INSTRUCTION UNIT 7-14 ADVANCED TECHNIQUES

15 ADVANCED TECHNIQUES UNIT 7-15

16 CALCULATIONS UNIT 7-16 ADVANCED TECHNIQUES

17 PROGRAMMER: JOB: MA602 MACHINE: DATE: PAGE: LOCATION NUMBER X Y LOCATION NUMBER X Y LOCATION NUMBER X Y NOTES: ADVANCED TECHNIQUES UNIT 7-17

18 NOTES UNIT 7-18 ADVANCED TECHNIQUES

19 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MA602 MACHINE: DATE: PAG E: INSTRUCTION ADVANCED TECHNIQUES UNIT 7-19

20 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MACHINE: DATE: PAG E: INSTRUCTION UNIT 7-20 ADVANCED TECHNIQUES

21 ADVANCED TECHNIQUES UNIT 7-21

22 CALCULATIONS UNIT 7-22 ADVANCED TECHNIQUES

23 PROGRAMMER: JOB: MA603 MACHINE: DATE: PAGE: LOCATION NUMBER X Y LOCATION NUMBER X Y LOCATION NUMBER X Y NOTES: ADVANCED TECHNIQUES UNIT 7-23

24 NOTES UNIT 7-24 ADVANCED TECHNIQUES

25 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MA603 MACHINE: DATE: PAG E: INSTRUCTION ADVANCED TECHNIQUES UNIT 7-25

26 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MACHINE: DATE: PAG E: INSTRUCTION UNIT 7-26 ADVANCED TECHNIQUES

27 ADVANCED TECHNIQUES UNIT 7-27

28 CALCULATIONS UNIT 7-28 ADVANCED TECHNIQUES

29 PROGRAMMER: JOB: MA604 MACHINE: DATE: PAGE: LOCATION NUMBER X Y LOCATION NUMBER X Y LOCATION NUMBER X Y NOTES: ADVANCED TECHNIQUES UNIT 7-29

30 NOTES UNIT 7-30 ADVANCED TECHNIQUES

31 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MA604 MACHINE: DATE: PAG E: INSTRUCTION ADVANCED TECHNIQUES UNIT 7-31

32 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MACHINE: DATE: PAG E: INSTRUCTION UNIT 7-32 ADVANCED TECHNIQUES

33 M A C H IN E A C T IV IT Y M A 301 P rog ra m m ing ADVANCED TECHNIQUES UNIT 7-33

34 CALCULATIONS UNIT 7-34 ADVANCED TECHNIQUES

35 PROGRAMMER: JOB: MA605 MACHINE: DATE: PAGE: LOCATION NUMBER X Y LOCATION NUMBER X Y LOCATION NUMBER X Y NOTES: ADVANCED TECHNIQUES UNIT 7-35

36 NOTES UNIT 7-36 ADVANCED TECHNIQUES

37 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MA605 MACHINE: DATE: PAG E: INSTRUCTION ADVANCED TECHNIQUES UNIT 7-37

38 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MACHINE: DATE: PAG E: INSTRUCTION UNIT 7-38 ADVANCED TECHNIQUES

39 M A C H IN E A C T IV IT Y M A 302 P ro gram m in g ADVANCED TECHNIQUES UNIT 7-39

40 CALCULATIONS UNIT 7-40 ADVANCED TECHNIQUES

41 PROGRAMMER: JOB: MA606 MACHINE: DATE: PAGE: LOCATION NUMBER X Y LOCATION NUMBER X Y LOCATION NUMBER X Y NOTES: ADVANCED TECHNIQUES UNIT 7-41

42 NOTES UNIT 7-42 ADVANCED TECHNIQUES

43 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MA606 MACHINE: DATE: PAG E: INSTRUCTION ADVANCED TECHNIQUES UNIT 7-43

44 PROGRAM WORKSHEET PROGRAMMER: PART NAME: MACHINE: DATE: PAG E: INSTRUCTION UNIT 7-44 ADVANCED TECHNIQUES