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1 AUSTRALIA CANADA USA UNITED KINGDOM SINGAPORE MALAYSIA Safetycare Australia Pty. Ltd. Telephone (03) Safetycare Inc. Telephone (905) Safetycare Inc. Telephone (800) Safetycare (UK) Limited. Telephone (0208) SafetyMax Corp Pte. Ltd. Telephone SafetyMax Sdn Bhd Telephone (603) The information contained in this Facilitator s guide is distributed and sold as a guide and for informational purposes only. Safetycare makes no representation or warranty as to the compliance of this program with any and all applicable laws of the purchaser's jurisdiction. 2. Safetycare's liability for any damages to the purchaser or to any other party shall not exceed the amount paid by the purchaser for the guide. In no event shall Safetycare be responsible for any indirect or consequential damages or loss of profits, even if Safetycare has been advised of the possibility of such damage. Some provinces/states do not allow the limitations or exclusion of liability for incidental or consequential damages, so the above limitations or exclusions may not apply to the purchaser. 3. This Facilitator s Guide is supplied as part of a subscription service. This guide is only to be used during a valid subscription period. Where a subscription is not valid, this guide may not be used. Facilitator s Guide WORKING WITH LATHES Copyright - All Rights Reserved

2 Working with Lathes CONTENTS Introduction to the Facilitator s Guide 3 Introduction to the Video Program; Working with Lathes 4 Transcript of Video Program 5 Part 1 - Workshop Safety 14 Part 2 - Lathe Components 15 Part 3 - Cutting Tools 17 Part 4 - Cutting Fluids 18 Part 5 - Making a Cut 19 Assessment 20 Answers 22 2

3 INTRODUCTION TO THE FACILITATOR S GUIDE Working with Lathes The aim of this Facilitator s Guide, when used in conjunction with the Video program, is to provide the facilitator with discussion points important to the overall development of the program and to allow participants the opportunity of discussing the impact the program may have on current work practices and whether in fact changes may be required. The time allocated to the program will be determined by which areas are seen as important to each Organisation, the time taken to develop the points made in the program and whether other data specific to your own environment is included in addition to, or instead of, the program examples. EACH FACILITATOR SHOULD CAREFULLY READ THE GUIDE DISCUSSION NOTES SUGGESTED AND PREPARE THEIR OWN INPUT ACCORDINGLY. The program transcript is included to allow your Organisation to fully research the program content and develop specific examples critical to the performance of your own workforce. Where the Video program is made available to small or remote sections of your Organisation, some other examples or discussion points may be preferred to suit the needs of these people and if so, should be developed prior to distribution of the program. Maximum benefit will then be obtained by your people. All information included in the Facilitator s Guide may be copied and distributed with the exception of the transcript of the Video program. Any information which is copied or distributed must only be used internally by the Organisation that purchased the guide. SCREEN SHOT FROM THE VIDEO PROGRAM 3

4 INTRODUCTION TO THE VIDEO PROGRAM Duration: 25 minutes The Lathe is one of the most versatile tools in use throughout industry today. It provides a quick and efficient means of shaping and drilling many types of metal and wood. This program covers the safe and correct use of the Lathe and includes: Workshop and operator safety Identification, correct use and maintenance of all components which make up the Lathe, including the Carriage, Headstock, Tailstock, Cross-slide, Top-slide and Compound Rest Correct procedure for changing the Spindle speed Step by step instruction on correct centering and mounting of work pieces Setting up the cutting tool and adjustment of the cutting speed and feed How to make rough and finish cuts The program is aimed at all Lathe operators from students to experienced operators as a refresher on safe and correct equipment usage. 4

5 TRANSCRIPT OF THE VIDEO PROGRAM Working with Lathes Copyright Safetycare. All rights reserved The lathe is a versatile tool in any workshop providing a quick and efficient means of removing metal from the work piece by rotating it and feeding a cutting tool against the work. When the cutting tool moves along the work piece to produce cylindrical shapes the action is called turning and when the tool is moved across the work to form flat surfaces this is called facing. Apart from turning and facing operations such as drilling, threading and reaming may be performed on the lathe with the aid of special equipment. In addition, there are special types of lathes that have been designed for specific purposes. The general purpose lathe is usually referred to as the centre lathe. Workshop Safety We must all have a genuine commitment to safety in the workplace and as you enter any workshop no matter how familiar the surroundings are to you, you must ensure that you are dressed appropriately for the job. That you are wearing protective clothing such as safety boots and goggles. The work area is clean and tidy. Your work area is well lit and that the focus of your work is highlighted and that you have sufficient space to safely perform your work. Lathe Components The lathe has five major parts that you'll become familiar with in order to establish a foundation for your working knowledge. These parts are; The bed The headstock The tailstock The carriage and; The feed mechanism. The bed is the part on the lathe that provides support to the other components; it's the foundation on which all other parts are fitted. 5

6 The accuracy of the lathe depends on the condition of the bed slide ways. Worn or damaged ways cannot provide accurate location or movement of the cutting tool. It's extremely important to protect the bed slide ways by; Cleaning the slides on a regular basis Oil the slides frequently Never place tools or other articles on slides Avoid dropping pieces of metal or equipment on the bed and; Protect the bed with a wooden block when fitting or removing equipment from the headstock spindle. The headstock houses the motor and provides the means to hold and rotate the work accurately. The headstock is fixed while the tailstock is moved along the bed and clamped into position to support the right hand edge of the work. The carriage holds the cutting tool and moves the tool with the required precise accuracy. The saddle is the part of the carriage that fits across and moves along the bed. The apron of the carriage is bolted to the front of the saddle and contains the mechanism for moving and controlling the carriage. The apron features the traversing handwheel, the feed selector, the feed lever and the leadscrew engagement lever. The saddle features; The tool post The cross slide The top slide The compound rest and; The screwed spindle fitted with a handle. Most centre lathes have some form of power feed mechanism to provide automatic movement to the cutting tool. Power feed can be applied to both the saddle and the cross slide. The feed mechanism features; The quick change gear box The feed shaft The lead screw The feed lever and; The leadscrew lever. 6

7 Operating the Lathe The most important thing to do before you attempt to operate the lathe is to make yourself familiar with all the parts and the function of each part. Above all, you must work safely and with any electrically powered equipment, you must know where the on/off power switch is. In this case it is located at the rear of the lathe. Make sure that the lathe is switched off until you're ready to use it, and always remember to switch it off directly after use. This simple rule will protect you and your workmates from accident and injury. There are particular procedures for the operation of each part of the lathe and you must be familiar with each of them, in order to carry out lathe operations with efficiency and accuracy. Using the Tailstock The body of the tailstock is fitted onto the base and has adjusting screws to enable a limited movement of the body on the base. This allows the tailstock centre to be accurately aligned with the headstock centre for parallel turning. The centering plate enables accurate offset of the tailstock. The tailstock is clamped to the bed by a clamp operated by a lever. This can easily be released allowing it to move the tailstock along the bed. The tailstock hand wheel can be rotated clockwise to extend the spindle from the body. The tailstock spindle most often has linear graduations marked on the side to indicate the extent of travel of the spindle. Operating the Carriage Preparation is the most important aspect of any job and there are a number of steps that you must take prior to attempting to operate the carriage. Clean the slide ways. Lubricate the slides. Check the oil level in the apron. Operate the automatic oiling system and if no such system is fitted to your lathe, make sure that all moving parts are lubricated. Then, locate and release the saddle clamping screw. The carriage controls are situated on the apron and by turning the large hand wheel anticlockwise the carriage will move to the left towards the headstock. 7

8 The carriage can then be moved gently against the headstock but you must ensure that no part of the saddle fouls against any of the equipment fitted to the headstock. In order to establish the maximum dimensions of work that can be turned on your lathe, you can measure the distance from the centre of the headstock spindle to the top of the cross lines. This will give you the maximum radius of the work that can be turned on its outside circumference. By clamping the tailstock flush with the end of the bed you ll be able to measure the maximum distance between centres. This will determine the maximum length of the work that can be fitted. Using the Cross Slide The cross slide operating handle is fitted to the top section of the apron. The maximum movement in the cross slide determines the maximum movement available to the tool for facing work. A graduated collar is fitted to the cross slide handle to enable accurate movements to be made to the cutting tool. You set the graduated collar by turning it to the required setting. Setting the Compound Rest The compound rest is set to an angle by; Switching off the motor Loosening the nuts that are clamping the rest Turning the rest to the required angle and; Then tightening the nuts that clamp the rest. The base of the rest is graduated in degrees to enable accurate setting of angles. Using the Top Slide The top slide is fitted with a graduated collar which allows for accurate movements to be made to the tool. To use the top slide you simply turn the handle of the top slide clockwise and the slide and tool post will move towards the headstock. Likewise, if the handle is turned anticlockwise, the slide and the tool post will move away from the headstock. 8

9 The tool post is fixed above the top slide and may provide positions for holding a number of different cutting tools. Operating the Headstock The headstock supports and drives the lathe spindle at a speed that may be varied by changing the belt positions or gear ratios. Levers are provided on the headstock to enable the gear ratios to be changed. The motor must be switched off before such gear changes are attempted. Larger lathes are fitted with a clutch that allows gear changes by disengaging the headstock drive from the driving motor. Changing the Spindle Speed For lathes fitted with a geared headstock you can change the spindle speed by following a simple exercise. Always start with the slower speed allowing the machine to warm up and to circulate the lubricating oil before engaging higher speeds. This is the exercise you should follow; Turn the motor off at the on/off switch Check that the clutch lever is in the disengaged position Set the feed direction lever to neutral Wind the carriage to the right clear of the headstock Check the oil level in the headstock Check that any attachments on the headstock spindle are secure Disengage the speed selector and rotate the spindle once to ensure all is clear Set the speed change levers to positions indicated on the chart to give the slowest speeds, and then; Turn the motor on Press the start button Firmly engage the clutch lever Allow the spindle to turn for a few revolutions Disengage the clutch Switch off the motor and allow it to stop by itself, never try to force the spindle to a halt. When you ve gained experience, the spindle speed may be changed without turning off the motor provided that the clutch has been fully disengaged. Now that you are familiar with the various parts of the lathe we can progress to attaching a work piece to the lathe. There are a number of accessories for the lathe that can be used depending on the nature of the work. 9

10 Centre the Work The key to accuracy in all lathe operations lies in the initial preparation of centering the work. If this is not done correctly all other steps to align the work and the cutting tool will be useless. There are a variety of ways in which the work can be centered but for our purposes we ll use a centre square and a scriber. Place the work piece in a vice. Remove all burrs from the ends of the work with a file. Then apply layout dye or chalk to both ends. Place the centre square firmly against the body of the work while keeping the rule flat on the end surface. With the scriber draw a line along the edge of the rule, turn the square over and draw another line. This is to allow for any error caused by misalignment of the rule. If no error exists both lines will coincide. If errors do exist two parallel lines will be scribed. This action is repeated to draw another set of lines at right angles to the first. The junction of the two lines or sets of lines will be the centre of the work piece. Place a punch at the intersection of the lines and strike it with a light hammer blow. This will mark the true centre of the work. Then drill a hole at the intersection so that the lathe centre will be able to support the work piece. Make sure you carry out all these steps at both ends of the work piece. Mounting the Work The work is mounted on the lathe by placing it between the lathe centres and you ll have to fit the centres to the headstock and tailstock. To fit the centre to the headstock you must; Place a protective wooden block on the lathe bed Remove any accessory that is mounted on the lathe spindle Clean the lathe spindle with a cloth and remove any lint Start the motor and check the live centres for trueness, then remove the lathe centre again Clean the lathe centre points and the work piece centre holds. After this preparation, a suitable drive plate can then be selected. Once again, make sure that the thread of the drive plate is clean. If using a thread type spindle or drive plate, apply a few drops of oil on the threads for lubrication. 10

11 Position the drive plate on the spindle and tighten the cam nuts. Then select a lathe carrier and fasten it on one end on the work piece. The bent tail of the carrier should be pointing outwards. Now move the tailstock to a position to suit the length of the work piece, and plant the tailstock into position by tightening the tailstock lever or nut. By holding the work piece in your left hand, place the centre of the work onto the headstock centre so that the tail of the carrier fits into the slot on the drive plates. Advance the tailstock spindle so that its centre meets the other centre of the work piece. This should be done until the dead centre of the tailstock enters the hole in the end of the work, and all end play is eliminated. Now turn the spindle hand wheel back so that there s slight end play and the tail of the carrier can move back and forward in its slot. Lift the tail as it sits in the drive plate slot to the top of the slot. Then let the tail fall within the boundaries of the slot. If it falls under its own weight and there s no end play between the work and the lathe centres, then the spindle hand wheel has been adjusted correctly. Cutting Tools In order to perform a lathe operation you need a cutting tool. Cutting tools are made from a variety of substances such as carbon steel, non-ferrous alloys and so on. There are different tools for different operations and you can refer to a monograph in order to determine which particular tool you ll need for the job at hand. Different operations and tools are referred to as a right hand or a left hand cut. Depending on the direction they must travel along the work to make the cut. To set up a right hand rough turning tool and the tool post you must; Mount the tool holder on the left hand side of the tool posts Make sure that the set screw is close to the tool post Set the tool holder at right angles to the tailstock or pointing slightly outwards Mount the rough cut tool bit into the tool holder making sure it extends only 12mm beyond the tool holder Tighten the tool holder set screw 11

12 Check the height of the tool bit by running in the tailstock and cross slide until the point of the tool bit is as close as possible to the point of the tail stock lathe centre Then make any necessary adjustments Once completed securely tighten the tool post screws to prevent the tool holder from moving under the force of the cut. The Feed and Depth of a Cut The feed is the distance that the cutting tool advances along the face of the work for each revolution of the spindle. Now this can be measured as the thickness of the chips. A feed of.05mm means that for each turn of the spindle the cutting tool moves.05mm along the work. Now the feed has an important relationship with the depth of cut. To produce accurate work as with a finishing cut a fine feed is required as with a small or light cut. On the other hand with rough work, when you re trying to remove metal as quickly as possible and accuracy is not important, the cut and the depth can be course and deep. Cutting Fluids All lathe operations require cutting fluids which provide a cooling and lubricating action that protects the edge of the cutting tool. This allows the sharpness to be maintained and the cutting speeds to be increased by lowering the temperature. By referring to the cutting fluids chart you can determine which fluid is appropriate for the metal you ll be working with. Making a Rough Cut When you ve set up the lathe correctly you re ready to make a cut after you have; Set the cutting tool to centre height and securely tightened the tool post screws Mounted the work piece between the centres Greased the work piece centre holes Made sure the work area is adequately lit Set the correct lathe speed for the material being cut Set the quick change gear box for the rough cut feed of half a millimeter and, Press the start button. 12

13 Now you can start the lathe, release the clutch and make the cut. Making a Finish Cut The purpose of the rough cut is to remove a sufficient amount of metal from the work piece so that; No faults are left on the outside of the bar and; There s sufficient metal left to perform the desired finish cut. A finish cut requires a slightly higher cutting speed and a much finer depth and feed for it to be accurate. After Each Operation It s important at the end of each operation and at the end of the day s work to clean up your work area and to store tools and accessories in the appropriate place. Further Study This video program will have given you a basic understanding of the working of a centre lathe, its various parts and the manner in which these parts are correctly adjusted. A good working knowledge of the lathe is necessary before you can attempt any work on this equipment and you can study this information in more detail by reading these basic skills manuals. Always keep in mind that safety in the workshop is of equal importance to developing skills on the lathe. Any knowledge and skill must be built on sound foundations. Once you feel you have a good knowledge of the basic operation of the lathe you may wish to try your hand at specific exercises. Again this range of basic skills manuals devoted to the lathe can guide you through such exercises. If you encounter any difficulty in understanding the lathe and its various components you should speak with your supervisor at work, or talk with your trade teacher. 13

14 PART ONE WORKSHOP SAFETY We must all have a genuine commitment to safety in the workplace and as you enter any workshop no matter how familiar the surroundings are to you, you must ensure that you: Are dressed appropriately for the job. That you are wearing protective clothing such as safety boots and goggles. The work area is clean and tidy. Your work area is well lit, and That the focus of your work is highlighted and that you have sufficient space to safely perform your work. DISCUSSION What PPE are you required to wear when using a lathe? 14

15 PART TWO LATHE COMPONENTS The lathe has five major parts that you'll become familiar with in order to establish a foundation for your working knowledge. These parts are; The bed The headstock The tailstock The carriage and; The feed mechanism. The bed is the part on the lathe that provides support to the other components; it's the foundation on which all other parts are fitted. The accuracy of the lathe depends on the condition of the bed slide ways. Worn or damaged ways cannot provide accurate location or movement of the cutting tool. It's extremely important to protect the bed slide ways by; Cleaning the slides on a regular basis Oil the slides frequently Never place tools or other articles on slides Avoid dropping pieces of metal or equipment on the bed and; Protect the bed with a wooden block when fitting or removing equipment from the headstock spindle. The headstock houses the motor and provides the means to hold and rotate the work accurately. The headstock is fixed while the tailstock is moved along the bed and clamped into position to support the right hand edge of the work. The carriage holds the cutting tool and moves the tool with the required precise accuracy. The saddle is the part of the carriage that fits across and moves along the bed. The apron of the carriage is bolted to the front of the saddle and contains the mechanism for moving and controlling the carriage. The apron features the traversing handwheel, the feed selector, the feed lever and the leadscrew engagement lever. The saddle features; The tool post The cross slide The top slide The compound rest and; 15

16 The screwed spindle fitted with a handle. Most centre lathes have some form of power feed mechanism to provide automatic movement to the cutting tool. Power feed can be applied to both the saddle and the cross slide. The feed mechanism features; The quick change gear box The feed shaft The lead screw The feed lever and; The leadscrew lever. DISCUSSION Go through the components of the lathe on the lathe in your workshop. 16

17 PART THREE CUTTING TOOLS In order to perform a lathe operation you need a cutting tool. Cutting tools are made from a variety of substances such as carbon steel, non-ferrous alloys and so on. There are different tools for different operations and you can refer to a monograph in order to determine which particular tool you ll need for the job at hand. Different operations and tools are referred to as a right hand or a left hand cut. Depending on the direction they must travel along the work to make the cut. To set up a right hand rough turning tool and the tool post you must: Mount the tool holder on the left hand side of the tool posts Make sure that the set screw is close to the tool post Set the tool holder at right angles to the tailstock or pointing slightly outwards Mount the rough cut tool bit into the tool holder making sure it extends only 12mm beyond the tool holder Tighten the tool holder set screw Check the height of the tool bit by running in the tailstock and cross slide until the point of the tool bit is as close as possible to the point of the tail stock lathe centre Then make any necessary adjustments Once completed securely tighten the tool post screws to prevent the tool holder from moving under the force of the cut. DISCUSSION What are the common lathe cutting tools used in your workshop? 17

18 PART FOUR CUTTING FLUIDS All lathe operations require cutting fluids which provide a cooling and lubricating action that protects the edge of the cutting tool. This allows the sharpness to be maintained and the cutting speeds to be increased by lowering the temperature. By referring to the cutting fluids chart you can determine which fluid is appropriate for the metal you ll be working with. DISCUSSION What cutting fluid chart do you refer to in your workshop? 18

19 PART FIVE MAKING A CUT Making a Rough Cut When you ve set up the lathe correctly you re ready to make a cut after you have: Set the cutting tool to centre height and securely tightened the tool post screws Mounted the work piece between the centres Greased the work piece centre holes Made sure the work area is adequately lit Set the correct lathe speed for the material being cut Set the quick change gear box for the rough cut feed of half a millimeter and, Press the start button. Now you can start the lathe, release the clutch and make the cut. Making a Finish Cut The purpose of the rough cut is to remove a sufficient amount of metal from the work piece so that: No faults are left on the outside of the bar and; There s sufficient metal left to perform the desired finish cut. A finish cut requires a slightly higher cutting speed and a much finer depth and feed for it to be accurate. DISCUSSION What are the specific Safe Work Procedures related to the lathe in your workplace? 19

20 ASSESSMENT WORKING WITH LATHES Name: Date:. I.D. (if applicable): Score 1. The houses the motor and provides the means to accurately hold and rotate the work: a) tailstock b) carriage c) headstock d) saddle 2. The most important thing to do before you attempt to operate the lathe is: a) to turn it on b) to make yourself familiar with all the parts and the function of each part c) pull the levers d) to traverse the handwheel in a familiar fashion 3. The tailstock is clamped to the bed by: a) a clamp operated by a lever b) the spindle c) buttons next to the on switch d) a lever operated saddle 4. Before operating the carriage the slide ways must be and : a) washed and shaved b) polished and dried c) cleaned and lubricated d) bright and sparkly 20

21 5. To establish the maximum dimensions of work that can be turned on your lathe: a) measure the size of clamps and their distance from the apron b) measure the distance between the carriage and the spindle c) measure the distance from the centre of the headstock spindle to the top of the cross lines. d) measure the headstock 6. The levers provided on the head stock enable: a) the clamps to come undone b) the tool post to move away from the head stock c) the motor to turn on and off d) the gear ratios to be changed 7. Always start the spindle with the allowing the machine to warm up: a) slower speed b) fastest speed c) highest speed d) super speed. 8. A finish cut requires a slightly higher cutting speed and a much finer and for it to be accurate: a) speed and material b) depth and feed c) clamp and motor d) all of the above 9. All lathe operations require cutting fluids which provide a: a) cooling and roughening action b) cooling and lubricating action c) spinning and heating action d) lubricating and heating action 10. In order to perform a lathe operation you need a: a) sander as referred to in the handbook b) hose as referred to in the monograph c) cutting tool as referred to in the monograph d) hammer as referred to in the handbook 21

22 ANSWERS TO ASSESSMENTS 1. C) Headstock. 2. B) To make yourself familiar with all the parts and the function of each part. 3. A) A clamp operated by a lever. 4. C) Cleaned and lubricated. 5. C) Measure the distance from the centre of the headstock spindle to the top of the cross lines. 6. D) The gear ratios to be changed. 7. A) Slower speed. 8. B) Depth and feed. 9. B) Cooling and lubricating action. 10. C) Cutting tool. 22