CNC Pro gram min g T ech niques - Industrial Press

1 CNCPro gram mingTech niquesAn In sider's Guide to Ef fec tive Meth ods and Ap pli ca tionsFirst Edi tionCNC Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - gram mingTech niquesAn In sider's Guide to Ef fec tive Meth ods and Ap pli ca tionsPe ter SmidIn dus trial Press , Mad i son Av e nueNew York, New York 10016-4078, Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - <<PAGE TO BE REPLACED>> Li brary of Con gress Cat a log ing-in-Pub li ca tion DataSmid, Pe ter CNC Pro gram ming Techniques: xxx/ Pe ter Smid. p. 0-8311-3158-6 1. Ma chine-tools--Nu mer i cal Con trol--Pro gram ming--Hand books, man u als, etc.,..S592 2000 '023--dc2100-023974 First Edi tionCNC Pro gram ming TechniquesIn dus trial Press Mad i son Av e nueNew York, NY 10016-4078Ed i tor: John CarleoCover De sign: Janet RomanoCopy right 2005.

2 Printed in the United States of Amer Rights Re book or parts thereof may not be re pro duced, stored in a re trievalsys tem, or trans mit ted in any form with out the per mis sion of the pub lish 2 3 4 5 6 7 8 9 10 CNC Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - CarleoJanet Romanoand Pat rick with out you, this book would not hap pen .. CNC Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - the Au thorPe ter Smid is a pro fes sional con sul tant, ed u ca tor and speaker, with many years of prac ti cal,hands-on ex pe ri ence, in the in dus trial and ed u ca tional fields. Dur ing his ca reer, he has gath ered anex ten sive ex pe ri ence with CNC and CAD/CAM ap pli ca tions on all lev els. He con sults to man u fac -tur ing in dus try and ed u ca tional in sti tu tions on prac ti cal use of Com put er ized Nu mer i cal Con trol tech -nol ogy, part pro gram ming, CAD/CAM, ad vanced ma chin ing, tool ing, setup, and many other re lated fields.

3 His com pre hen sive in dus trial back ground in CNC pro gram ming, ma chin ing and com pany ori -ented train ing has as sisted sev eral hun dred com pa nies to ben e fit from his wide-rang ing knowl Smid s long time as so ci a tion with ad vanced man u fac tur ing com pa nies and CNC ma chin eryven dors, as well as his af fil i a tion with a num ber of Com mu nity and Tech ni cal Col lege in dus trial tech -nol ogy pro grams and ma chine shop skills train ing, have en abled him to broaden his pro fes sional andcon sult ing skills in the ar eas of CNC and CAD/CAM train ing, com puter ap pli ca tions and needs anal -y sis, soft ware eval u a tion, sys tem bench mark ing, pro gram ming, hard ware se lec tion, soft ware cus -tom iz ation, and op er a tions man a ge the years, Mr. Smid has de vel oped and de liv ered hun dreds of cus tom ized ed u ca tional pro -grams to thou sands of in struc tors and stu dents at col leges and uni ver si ties across United States, Can -ada and Eu rope, as well as to a large num ber of man u fac tur ing com pa nies and pri vate sec tor or ga ni -za tions and in di vid u has ac tively par tic i pated in many in dus trial trade shows, con fer ences, work shops and var i oussem i nars, in clud ing sub mis sion of pa pers, de liv er ing pre sen ta tions and a num ber of speak ing en gage -ments to pro fes sional or ga ni za tions.

4 He is also the au thor of ar ti cles, monthly mag a zine col umns, and many in-house pub li ca tions on the sub ject of CNC and CAD/CAM. Dur ing his many years as a pro -fes sional in the CNC in dus trial and ed u ca tional field, he has de vel oped tens of thou sands of pages ofhigh qual ity train ing ma te ri ter Smid is also the au thor ofCNC Pro gram ming Hand book, A Com pre hen sive Guide to CNC Pro gram mingFanuc CNC Cus tom Mac ros: Prac ti cal Re sources for Fanuc Cus tom Macro B Us ersBoth hard cover books have been pub lished by In dus trial Press . au thor al ways wel comes com ments, sug ges tions and other in put from ed u ca tors, stu dentsand in dus trial us can send e-mail to the au thor from the CNC Pro gram ming Tech niques page at Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - would like to ex Press my most sin cere thanks to all programmers, ma chin ists, op er a tors, en gi -neers, stu dents and many other read ers and us ers who made my two pre vi ous books - also CNC ori -ented - such a great suc cess.

5 Both were pub lished by In dus trial Press , Inc. (New York, NY, USA): CNC Pro gram ming Hand book, Sec ond Edi tion with CD-ROMA Com pre hen sive Guide to CNC Pro gram mingISBN: (0-8311-) 3158-6 and Fanuc CNC Cus tom Mac ros, with CD-ROMPrac ti cal Re sources for Fanuc Cus tom Macro B Us ersISBN: (0-8311-) 3157-8 This third hand book also re lates to the sub ject of CNC pro gram ming, this time from a some whatdif fer ent an gle. First, there sev eral pro gram ming sub jects that are vir tu ally im pos si ble to find any -where else, for ex am ple, how to pro gram cams or ta pered end mills. Other, more com mon, sub jectsare cov ered in a great depth, such as the cov er age of cut ter ra dius off set or thread mill ing. As in my pre vi ous pub li ca tions, I have in cluded many over all and de tailed draw ings, to help vi su al -ize the sub ject or pro ce dures cov ered. Where ap pli ca ble, a com plete pro gram ming ex am ple is pro -vided, or - at least the most sig nif i cant part is view of the re cent, and rather sig nif i cant, emer gence of met ric sys tem in many North Amer i canin dus tries, par tic u larly in the USA, I have fo cused on more ex am ples pre sented in met ric units thanthose in im pe rial units.

6 Work ing on the prem ise that a pro fes sional CNC pro gram mer should have noprob lem work ing with ei ther units se lec tion (af ter all, num ber are num bers), many ex am ples in thishand book em pha size the met ric sys tem. For bal ance, a sig nif i cant num ber of ex am ples us ing im pe rial units are also in cluded. Speak ing of im pe rial units - in my pre vi ous books, I had used the term Eng -lish units in stead. It may seems friv o lous, but the fact is that mod ern Great Brit ain is now a met riccoun try and the so called Eng lish units are the thing of the past - of the im pe rial era in Brit ish his also feel that I should men tion the re la tion ship of this book to the CNC Pro gram ming Hand terms of fo cus, these are very dif fer ent publications. CNC Pro gram ming Tech niques is a book thatdoes not re place my pre vi ous books, but com ple ments them in a spe cial way. In terms of sub jectscov ered, there are mi nor sim i lar i ties in some chapters, but the cov er age of each sub ject is fresh, andwith much more de tail provided.

7 At the end of the book, I had in cluded ref er ences to sub jects cov ered in the CNC Pro gram ming Hand book. My feel ing was that those read ers who may need some ad di -tional back ground will ben e fit from these ref er ences. On the other hand, those, who do not need theback ground can safely ig nore those few pages and ex plore the sub jects cov ered in this book only. I sin cerely hope that this book will help you be come even a better CNC pro gram mer (or even abetter CNC Operator) by un der stand ing not just the 'hows' but also the 'whys' of many pro gram ming tech niques . Thanks you for your con tin u ing in ter ter SmidNovember 2005 CNC Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - OF CONTENTS1 - PART PROGRAM DEVELOPMENT1 Pro gram De vel op ment Draw ing 1 Draw ing Eval u a te rial and Setup 3 Part Reference Ori en ta tion.

8 3Se lect ing Part ing Se lec tion 4 Identifying Ma chin ing Op er a tour Mill cu lar Pocket Mill Mill Drill mary of Tools chin ing Data 10 Spin dle ting ing tails of Op er a tions 11 Tool 1 - Face Mill 2 - Out side Con 2 - Cir cu lar 3 - Slot Mill 4 - Spot Drill 5 - Drill 6 - Tap plete Pro - CALCULATING CONTOUR POINTS23 Tools and Knowl edge 23 Math e mat i cal ga nized Ap cess of Cal cu lat ing XY Coordinates 25 Step 1 - Es tab lish the Main Contour 2 - Fill-in the Co or di nate 3 - Iden tify Calculation 4 - Helpful Ideas for 5 - Cal cu la tions for Zone 6 - Cal cu la tions for Zone dat ing Co or di nate ing the CNC Pro Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - - FORMULAS FOR CONTOURING33 Con tour Point Between Two Lines (Lathe)

9 33 Con tour Point Between Line and Arc 34In ter sect ing Con tour gent Con tour cu lat ing the Sharp Point 39 Con tour Point Between Two Arcs 40In ter sect ing gent - USING CUTTER RADIUS OFFSET43 Gen eral Con cepts 43 Ben e fits Of Cut ter Radius Off trol ling Cut ter Ra dius Off set Com mands 45 Com mands ing the D-off set sic Programming Tech niques 46 Cut ter Radius Ac ti va ter Radius Ap pli ca ter Radius Can cel la set Stored Amount 47 Equi dis tant Centerline - G40 dis tant Cen ter line - G41/G42 ing Di men sions - G40 ing Di men sions - G41/G42 dius vs Di am e tour Lead-In and Lead-Out 49 Methods For Lead-In - Linear ods For Lead-In - Arc ods For Lead-Out - Lin ear Mo ods For Lead-Out - Arc Mo ter nal Con tours 54 Linear Slot Machining.

10 54 Cir cu lar Slot Ma chin ish ing Internal tain ing Di men sional Sizes 58Ba sic dling Di men sional Tol er Cutter Radius Offset Er rors 60 Com mon Programmed Too Late or Too Start or End on an Nose Ra dius Off set 62 Com mand Point and Ra dius Tip mon Tool Nose Radius Er of ContentsCNC Programming TechniquesCopyright 2006, Industrial Press Inc., New York, NY - - PART REVERSAL IN MILLING67 Pro ject De scrip tion 67Ma te rial and Setup te rial Re moval 68Ma chin ing Pro cess 69 Clamp ing 1 ..69 Clamp ing 2 ..70 Pro gram Zero Se lec tion 70 First Clamp ond Clamp gram ming Methods 72 Tool Length Settings 72 First Clamp ond Clamp the WORK OFFSET Method - G54-G55 74 Com mon Toolpath 76 Pro gram List ing - WORK OFFSETS G54-G55 77 Pro gram List ing - WORK OFFSETS G54-G55 - with Subprograms 79Us ing the LO CAL CO OR DI NATES Method - G52 81 Pro gram Listing - LOCAL COORDINATE SYSTEM G52 83Us ing the DA TUM SHIFT Method - G10 85 Pro gram List ing - DATUM SHIFT G10 86 Summary 886 - USING TAPERED END MILLS89 Types of Ta pered End Mills 89 Tool Ma te of Taper An Tip Ta pered End Tip Tapered End Diameter Cal cu la tion