ChabotCollege
Course Outline for Machine Tool Technology 71B - page 1
Fall 2010
ChabotCollegeFall 2010
Course Outline for Machine Tool Techology 71B
NUMERICAL CONTROL PROGRAMMING II
Catalog Description:
71B – Numerical Control Programming II4 units
(May be repeated 3 times)
Intermediate programming and operating three-axis computer numerical controlled drilling and milling machining centers. Instruction includes intermediate contouring, helical interpolation, thread milling, sub programs, basic macro programming, conversational programming, programming with DXF files, program coding and preparation, process planning, fabrication of intermediate three-axis drill and mill parts, and laboratory “first article” inspection reports. Prerequisite: Machine Tool Technology 71A (completed with a grade of “C” or higher). 2 hours lecture, 6 hours laboratory.
[Typical contact hours: lecture 35, laboratory 105]
Prerequisite Skills:
Before entering the course the student should be able to:
- set tool length offsets;
- set fixture offsets;
- create CNC mill part programs;
- edit CNC mill part programs on machine controllers;
- write point-to-point drilling and tapping programs;
- write simple contouring programs;
- test run and fabricate simple CNC mill parts;
- calculate feeds, speeds, and dwell times;
- calculate cutter locations with a hand calculator;
- calculate polar coordinate positions;
- use subprograms for looping and repetitive operations;
- solve simple trigonometry problems;
- use the control math functions to calculate cutter locations;
- transfer edited programs from the machine’s control to computer;
- use a computer to write and transfer part programs across a network;
- inspect fabricated parts on a coordinate measuring machine;
- write a “first article” inspection report for each assigned project.
Expected Outcome for Students:
Upon completion of the course, the student should be able to:
- set tool length offsets with both touch probes and laser tool setters;
- set fixture offsets with edge finders and touch probes;
- construct basic process plans;
- create intermediate CNC contouring programs;
- use subprograms for looping and repetitive operations;
- create XY, XZ, and YZ arc toolpaths;
- write helical interpolation and thread milling programs;
- create conversational milling and drilling programs;
- generate mill tool paths from a DXF file;
- calculate intermediate cutter locations;
- test run and fabricate intermediate CNC mill parts;
- edit CNC mill part programs on machine controllers;
- solve intermediate trigonometry problems;
- use a computer to write and transfer part programs across a network;
- inspect fabricated parts on a coordinate measuring machine;
- write a “first article” inspection report for each assigned project.
Course Content (Lecture):
- Work surface programming
- Cutter compensation
- Tool and fixture offsets
- Sub programs
- Program format
- Preparatory and miscellaneous codes
- Canned cycles
- Inspection techniques
- First article inspection
- Lab inspection reports
- PVS-14 inspection scanner
- Work holding devices
- Vacuum plates
- IBAG Vac-Mat system
- Mitee-Bite clamps
- Helical interpolation
- Feed plane and initial plane
- Calculator functions
- Thread milling
- Thread gages
- Go - No Go gages
- XY, XZ, and YZ arcs
- G17, G18, G19
- Hurco mill conversational programming
- Machine programming functions
- Conversational vs ISNC programming
- ProtoTrak mill conversational programming
- Event programming
- Special functions – subroutines, engraving, pocketing
- Touch probe operation
- Touch probe functions
- Aligning the machine’s axes with part edges
- In-process inspection
- Intermediate contouring
- Cutter diameter compensation
- Cutter location calculation
- Tool path generation using DXF files
- Hurco DXF input
- ProtoTrak DXF input
- Direct data input into the machine’s control G10
- Fixture offsets
- Tool length offsets
- Beginning macro programming
- Parametric programming and machine variable functions
- CNC software applications
- Machining center simulator functions and operation
- Automatic tool setters
- Touch probes
- Laser tool set stations
Course Content (Laboratory):
- Techniques:
- Set tool length offsets with touch and laser probes
- Set fixture offsets with edge finders and touch probes
- Establish machine primary axes using a touch probe
- Create G-code part programs from engineering drawings
- Create conversational programs from engineering drawings
- Generate tool paths from DXF files
- Fabricate programmed parts
- Proof programs on machine tool simulators
- Test run programs
- Edit part programs in the CNC controller and save them to a computer
- In-process inspection on the machine using a touch probe
- Inspect parts with a coordinate measuring machine
- Inspect parts with manual inspection tools
- Safety:
- Safe operation of the CNC machining centers
- Safe program proofing procedure
Methods of Presentation:
- Lecture, informal with student questions encouraged
- Powerpoint presentations, videos, instructor created movies, and overhead transparencies
- Demonstrations
Assignments and Methods of Evaluating Student Progress:
- Typical Assignments
- Homework: 1-3 worksheets each week on the material covered in the text and in lecture.
Examples: Sketch the trough project, draw in the tool tangency locations, and calculate their Cartesian coordinate positions. Write a process plan to machine the rotor project using sub programs to rough and finish the outer contour and drill the 7/32Ø holes thru. Have it approved by the instructor.
- Laboratory assignment: Following your approved process plan, write a program to machine the rotor project. Load the program into the CNC machining center and test run each tool path operation checking for accuracy and proper tool path. Run the program and fabricate the part. Inspect the part on the coordinate measuring machine and create a “first article” inspection report. Did the part pass inspection? If not, why?
- Methods of Evaluating Student Progress
- Homework
- Quizzes
- Written laboratory inspection report on each part project
- Fabricated parts checked to be accurate size and shape
- Midterm examinations
- Final examination
Textbook(s) (Typical):
Haas VF2 Mill Programming Manual
This is the propgramming manual for specific equipment in Chabot's Machine Tool Technology lab. It is the standard for all operations and programming functions for our equipment.
Special Student Materials:
- Machine shop approved safety goggles
- Sharp EL-531W scientific calculator
- Plastic circle template, 6” rule, protractor, compass, three inch 30-60° and 45° triangle
- USB drive – 1gb minimum
- Headphones – 1/8” stereo jack
- Combination or keyed padlock
Revised: 9/29/09;
Ashley Long/Mike Absher