Probing on CNC Machines

By SK Sinha

This book is the revised edition of the same book published in 2020. There are modifications at several places, apart from certain additions, to make the descriptions easier-to-understand and more elaborate. The productivity of a CNC machine can be greatly increased if the set-up time and inspection time are reduced, by automating these time-consuming processes. The technique broadly involves automatic measurement of certain dimensions, and taking decisions, based on the result of measurement. This process is referred to as probing. A very common example is finding the center of a bore or measuring the depth of a pocket. This is called work probing . Tool probing , on the other hand, probes the tools and automatically updates the offset values, greatly reducing the setup time. The present text explains the basic probing techniques, and describes the basic hardware required. The book assumes that the reader has some basic idea of G-code programming and Fanuc Custom Macro B. Other than that, no background is assumed. If required one may refer to the book, " Macro Programming Fundamentals, " by the same author, for basic information about macro programming. The present book is a part of another book by the same author, " Computer-Aided Manufacturing: CNC Lathe, Probing and FMS ." Therefore, if one already has the CAM (Computer-Aided Manufacturing) book, this book need not be purchased. In fact, even the Macro Programming Fundamentals book is included in the CAM book which is in form of a handbook for CNC lathe, covering almost everything related to programming, tooling and operation. This book is available at amazon.com at a lower price (in equivalent currency). A sample program from the present book would give an idea of the method of presentation: O8000 (LOCATING HOLE CENTER ON MILL); (This program can be edit-protected) G21 G94; #100 = (X coordinate at the initial position A stored. Refer to the table shown in Fig. 16) G91 G31 X−200 F200; (Approaches position B) G00 X2; (Backs off after hitting and stopping) G31 X−5 F10; (Approaches position B again, for a second hit) #101 = (X coordinate of the center of the spherical tip stored, at position B) G31 X200 F200; (Approaches position C) X−2; (Backs off after hitting and stopping. G00 is implied) G31 X5 F10; (Approaches position C again, for a second hit) #102 = (X coordinate of the center of the tip stored, at position C) #500 = [[#101 + #102] / 2]; (X coordinate of the center of the bore calculated) G90 X#100; (Probe moves to position A) G91 G31 Y−200 F200; (Approaches position D) Y2; (Backs off after hitting and stopping) G31 Y−5 F10; (Approaches position D again, for a second hit) #103 = (Y coordinate of the center of the tip stored, at position D) G31 Y200 F200; (Approaches position E) Y−2; (Backs off after hitting and stopping) G31 Y5 F10; (Approaches position E again, for a second hit) #104 = (Y coordinate of the center of the tip stored, at position E) #501 = [[#103 + #104] / 2]; (Y coordinate of the center of the bore calculated) G90 X#500 Y (Probe moves to the center of the hole) G65 P9000; (Program O9000 is a macro to shift the current workpiece zero point to the current tool position. This macro is discussed in the next section) M30;

• Format: Paperback
• Language: English
• ISBN: B08Q5QGGRY
• ISBN13: 9798577916558
• Release Date: December 2020
• Publisher: Independently published
• Length: 67 Pages
• Weight: 0.24 lbs.
• Dimensions: 9.0" x 0.2" x 6.0"