background image

What Not To Do When Cutting Threads

Do not disengage the half-nut lever. Do not shift the powerfeed speed lever. If you are

cutting between centers don’t remove the lathe dog until the tread is finished and

tested, and don’t disturb the spindle while the work is off the centers.

When you think the thread is finished and ready for testing, and only if absolutely

necessary, remove the work from the center, leaving the lathe dog attached. Then test

the thread. If it does not fit properly and you have to remove another chip or two, place

the workpiece back in the centers exactly where it had been. Then remove the hips and

test again. Repeat until are finished.

Finishing Off a Threaded End

After cutting a thread and before removing the threading tool, chamfer the end. This

improves its appearance and removes sharp corners and burrs. It also aids the screws as

it engages a nut or threaded hole.

Cutting Threads on a Taper

Cut threads on a taper the same as on a straight shaft, except in the setup of the tool.

Set the threading tool at 90 degree to the axis of the taper, rather at 90 degree to its

surface (Figure 15.6) 

Figure 15.6 When cutting a thread on a taper,

set the threading tool at 90 degree to the axis of the taper.

15-5

For Assistance: Call Toll Free 1-800-476-4849

Midas 1220 XL Operator’s Manual

Summary of Contents for Midas 1220 XL

Page 1: ...MIDAS 1220 XL COMBINATION LATHE MILL DRILL OPERATOR S MANUAL Updated August 2008 170 Aprill Dr Ann Arbor MI USA 48103 Toll Free 1 800 476 4849 www smithy com ...

Page 2: ...g recording or otherwise without prior written permission of Smithy Co For information on getting permission for reprints and excerpts comments or suggestions contact info smithy com While every precaution has been taken in the preparation of this manual Smithy Co shall not have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indi...

Page 3: ...d 6 2 Tailstock 6 2 Three Jaw Chuck 6 2 Selecting Location 6 4 Cleaning and Lubricating the MI 1220 LTD 6 4 Oiling the Headstock 6 5 Oiling the Ways 6 5 Oiling the Carraige 6 5 Oiling the Tailstock 6 6 Oiling the Apron 6 6 Oiling the Leadscrew 6 7 Oiling the Compound Angle Toolpost 6 7 Setting Up Your MI 1220 XL 6 8 Setting Lathe and Mill Speeds 6 8 Adjusting Belt Tension 6 9 Adjusting Gibs 6 10 R...

Page 4: ...ff Thread Cutting and Facing Tools 10 3 Boring and Inside Threading Tools 10 3 Chapter 11 Setting Up with Centers Collets and Chucks Centering 11 1 Centering a Round and Rectangular Steels 11 2 Mounting Work between Centers 11 4 Using a Clamp Dog 11 4 Setting Up Work on Mandrel 11 6 Steady Rest and Follow Rest 11 6 Setting Up Work in a Chuck 11 8 Mounting Work in a Four Jaw Independent Lathe Chuck...

Page 5: ...utting Threads on a Taper 15 5 Chapter 16 Lathe Drilling and Boring Reaming 16 1 Boring 16 2 Cutting Internal Threads 16 4 Cutting Special Form Internal Threads 16 5 Chapter 17 Cutting Off or Parting with a Lathe 17 1 Chapter 18 Milling 18 1 Chapter 19 Workholding Mounting to the Table 19 1 Using a Vise 19 1 Dividing Heads 19 2 Rotary Tables 19 2 Chapter 20 Holding Milling Cutters Arbors 20 1 Coll...

Page 6: ......

Page 7: ...with the names of all the parts of your Smithy machine q Allen Wrench 4mm Item C30540 Quantity 1 q Allen Wrench 5mm Item C30542 Quantity 1 q Allen Wrench 6mm Item C30537 Quantity 1 q Allen Wrench 8mm Item C30536 Quantity 1 q Wrench 14 mm Item 81 500 Quantity 1 q Arbor JT33 MT3 No Tang Item C30523 Quantity 1 q Drift MT2 Item C30558 Quantity 1 q Dead Center MT3 Item 41 003 Quantity 1 q Dead Center M...

Page 8: ...h Item C30143 Quantity 2 q Gear 30 Teeth Item C30144 Quantity 1 q Gear 60 Teeth Item C30159 Quantity 1 q Gear 63 Teeth Item C30160 Quantity 1 q Jaws 3 5 Item 9 10 Quantity 1 set of 3 q Key Lathe Chuck Item C30532 Quantity 1 q Key Drill Chuck Item C30533 Quantity 1 q Open End Wrench 8 10mm Item C30539 Quantity 1 q Open End Wrench 17 19mm Item C30535 Quantity 1 q Adapter Precision End Mill Item 65 0...

Page 9: ...uantity 1 q Nut 3 8 16 Item 7 6 Quantity 1 q Washer Flat 5 16 Item 7 8 Quantity 1 q Washer Anti Back Lash Shim Item 82 050 Quantity 3 q Vise Bracket Bolt 3 8 x 1 1 4 Item 36 610 Quantity 2 q Plug Drill Chuck Arbor Item S12898 Quantity 1 q Vise 0 90 Degrees Adjustable Angle 3 1 4 Jaw Item 32 110 Quantity 1 q Carbide Bit Set Item 43 000 Quantity 1 q Machine Tool Basics DVD Item 12 004 Quantity 1 q C...

Page 10: ...Missing Items If you find that an item is missing or defective from your Quick Start Tool Pack Call Us TOLL FREE 1 800 476 4849 or send an e mail to info smithy com within 30 days of receiving your machine so that we may assist you immediately Our sales and service technicians are available 8am to 5pm ET Mondays to Fridays iv For Assistance Call Toll Free 1 800 476 4849 Midas 1220 XL Operator s Ma...

Page 11: ...ions not covered in this operator s manual please call Smithy Co Our trained technicians will help you with any machining problems you may have You can reach them by dialing 1 800 476 4849 Monday through Friday 8 00 am to 5 00 pm Eastern time We are always interested in your suggestions to improve our products and services Feel free to contact us by phone or in writing If you have comments about t...

Page 12: ...erything and put everything in its place 5 Keep children away from the machine while it is in use Childproof your shop with padlocks master switches and starter keys or store the machine where children do not have access to it 6 Wear appropriate clothing Avoid loose fitting clothes gloves neckties or jewellery that could get caught in moving parts If you have long hair tie it up or otherwise keep ...

Page 13: ... 14 Keep your mind on your work Pay attention to these simple rules and you will spend many safe enjoyable hours in your workshop Remember Your safety largely on your practices Modifying your machine may void the warranty and create potential hazards Safety 2 2 Or Visit www smithy com ...

Page 14: ... change lathe speeds adjust the belts in the main belt drive system This system uses three pulleys the motor pulley floating idler pulley and spindle pulley To run the lathe at lower turning speeds use two belts Install one between the motor and idler pulleys and the other between the idler and spindle pulleys To increase the speed move the spindle belt in two more positions on the pulleys For hig...

Page 15: ...is thin film of protective oil over all parts that might rust especially ground finished parts Never lay wrenches cutting tools files or other tools across the ways of your lathe The slightest dent or burr could impair its accuracy Before inserting collars centers adapters or drawbar attachments in either the spindle or tailstock spindle wipe them with a clean oily rag Also wipe all internal surfa...

Page 16: ...tion It is heavy strong and built for absolute rigidity The two ways on the top are the tracks on which the carriage and tailstock travel To maintain an exact relationship between toolpoint and workpiece from one end of the machine to the other the ways must be absolutely true and accurately aligned to the line of centers and to one another 5 1 For Assistance Call Toll Free 1 800 476 4849 21 20 19...

Page 17: ...hind B meshes with D Note the top two gears are permanent 4 Compound Rest Mounted on the cross slide the compound rest swivels to any angle horizontal to the lathe axis to produce bevels and tapers Cutting tools fasten to a toolpost on the compound rest The calibrations on the front of the base are numbered in degrees from 60 degree right to 60 degree left 5 Cross Slide The T slotted cross slide F...

Page 18: ...feed Select the thread pitch for threading or the feed rate for turning by changing the four change gears on the right side of the gear box Figure 5 4 The gearbox houses the belts and change gears 9 Half nut Engagement Lever This lever located on the apron transmit power to the carriage when rotated 90 degrees to the right 10 Half nut Speed Selector The two speed selector for powering the leadsrew...

Page 19: ...dle nose which has an MT4 taper rotates the workpiece and drives lathe chucks and other work holding devices All attachments such as three and four jaw chucks bolt to the spindle flange either directly or via an adapter plate 15 Leadscrew The leadscrew which runs the length of the bed moves the carriage for lathe turning or thread cutting It works both manually and under power You can also use it ...

Page 20: ...d cover off you can adjust the mill belt tension 19 Millhead Height Adjustment Unlock the mill head lock and place the height adjustment handle in one of the three holes in the black collar Turn the collar to raise and lower the millhead 20 Mill Spindle The mill spindle Figure 5 7 attaches to the quill which moves in and out of the head The quill lock keeps the quill still when you install or remo...

Page 21: ...Figure 5 8 To offset the tailstock adjust the base locking bolts 5 6 Or Visit www smithy com Basic Parts of the MI 1220 XL Right Tresle Setscrew Tailstock Setover Screw Tailstock Base Locking Bolts ...

Page 22: ... terminal about the damage Failure to notify both parties can complicate and or invalidate a claims process Trucking company terminals usually have forklifts to assist customers It s most conven ient to transport the machines in trucks without canopies and large vans Uncrating and Positioning the Machine The machine is assembled inspected and ready to go on its stand when you receive it It s wrapp...

Page 23: ...the flange of the support column remove it too Figure 6 2 Remove the millhead and column from the lathe head 2 Lock the millhead locking handle Figure 5 1 3 Lift the millhead and column off the lathe head Figure 6 2 You may have to rock it back and forth while lifting it Tailstock 1 Loosen the tailstock locks Figure 5 1 and pull the tailstock off the end of the bed The gib and the locking pin will...

Page 24: ... not let any part of your body come between the machine and the stand Bolt the machine to the stand using one flat washer and one lockwasher per bolt Before permanently anchoring the machine you may want to level the bed Figure 6 4 The bed is rigid and supports itself but having a level bed simplifies many setup operations Use a precision level both along and across the bed Figure 6 5 Shim up any ...

Page 25: ... floor is wood make sure it can support the machine and workbench Brace it if necessary to prevent sagging or settling 5 Make allowances at the back of the machine tool at the end and above it for later additions attachments and or accessories Provide clearance on the left end for bar stock to be fed through the spindle If you are considering placing more than one machine in an area allow enough f...

Page 26: ...ry add oil until it is half full The oil fill plug is at the back of the headstock above the motor Figure 5 5 Be careful no to overfill it If you have to top it with oil pour in only an ounce at a time and wait to see the results in the sight glass Too much oil will make the motor lug and sling oil from behind the chuck and inside the belt box Oiling the Ways 1 Run the carriage as far to the left ...

Page 27: ...the compound slides Oiling the Tailstock 1 Oil the buttons on top of the tailstock Figure 6 8 Figure 6 8 Oil the two buttons on the top of the tailstock Oiling the Apron 1 Put oil in the button just behind the cross slide handwheel Figure 6 7 2 Put oil in the button at the back of the cross slide Figure 6 7 6 6 Or Visit www smithy com Uncrating and Setting Up the MI 1220 XL ...

Page 28: ...few drops of oil along the leadscrew and feed shaft Oiling the Compound 1 Put oil in the two buttons on the top Oiling the Mill Drill Clutch 1 Put oil in the button on top of the clutch housing Figure 6 10 Figure 6 10 Oil the clutch housing button To keep your machine in peak condition lubricate it daily after removing any debris 6 7 For Assistance Call Toll Free 1 800 476 4849 Midas 1220 XL Opera...

Page 29: ...ave of the idler pulley For 160 rpm set the idler pulley to the lathe spindle pulley belt on the smallest sheave of the idler pulley to the largest sheave of the spindle pulley position C Move it in one sheave for 250 rpm position D and one more for 400 rpm position E Table 6 1Setting Lathe speeds RPM For the higher speeds remove the two small belts and use the single long belt from the motor pull...

Page 30: ...ng belt the spring at the bottom of the idler pulley brack et holds the idler pulley so it does not fall onto the motor pulley To adjust the tension on the spring loosen the pivot shaft Figure 6 11 and tighten or loosen the spring as need ed Then retighten the shaft Figure 6 11 Adjust the spring tension on the idler pulley bracket C X B A 3 2 1 1 2 3 4 4 3 2 1 A4 X B1 B4 C1 315 A3 X B1 B3 C1 630 A...

Page 31: ...e should be the same in both directions if it is not the gib is not adjusted evenly If you feel more handwheel resistance when the cross slide is going away from you the leading edge of the gib is too tight Back off the setscrew closest to you a little to relieve the tension If there is more resistance when the table is coming toward you the leading edge of the gib is too tight and you should adju...

Page 32: ...e the screw seat can not move 2 Tighten the cap nut so the handwheel is secure 3 Turn the handwheel one way then the other If a gap opens and closes between the dial and screw seat you must install one or more shim washers ask a Smithy technician about our antibacklash shim washer kit K99 190 To install shims remove the handwheel key washer and the outer part of the dial and spring Remove the inne...

Page 33: ...emble the screw seat onto the cross slide Longfeed 1 Tighten the setscrew on the bottom of the right trestle so the bushing is tight Figure 5 7 2 If there is still excess backlash remove the cap nut hand crank and key 3 Remove the washer outer dial spring and inner dial hub key 4 Install as many shim washer as possible between the bearing and dial Then reassemble Running In Though all Smithy machi...

Page 34: ...red button to stop it lift the cover over the rocker switch and push the rocker switch either up or down to reverse the motor s rotation 4 During the run in try the controls Get a feel for your machine 6 12 For Assistance Call Toll Free 1 800 476 4849 Midas 1220 XL Operator s Manual ...

Page 35: ...1528 2038 3057 7 16 437 524 611 698 786 873 960 1048 1135 1222 1310 1747 2621 1 2 382 458 535 611 688 764 840 917 993 1070 1146 1529 2293 5 8 306 367 428 489 550 611 672 733 794 856 917 1223 1834 3 4 255 306 357 407 458 509 560 611 662 713 764 1019 1529 7 8 218 262 306 349 393 426 480 524 568 611 655 874 1310 1 191 229 267 306 366 372 420 458 497 535 573 764 1146 1 1 8 170 204 238 272 306 340 373 ...

Page 36: ...tions needed to get the desired feet per minute fpm cutting speed Lathes cut threads in various numbers per inch of material threaded according to the operator s needs The Midas 1220 XL cuts threads to metric or inch standards In thread cutting the carriage carries the thread cutting tool and moves by rotating the leadscrew Figure 5 1 The basic principle is that the revolving leadscrew pulls the c...

Page 37: ...pindle s for threading turning and facing To change the thread pitch tpi replace the gears per Table 7 2 Table 7 2 Gear Ratios Threads Per Inch Metric Pitches 1 2 A B C D 003 006 30 60 27 63 30 15 70 32 40 45 28 14 70 32 40 42 26 13 70 32 40 39 24 12 70 32 40 36 22 11 70 32 40 33 20 10 70 32 40 30 18 9 70 27 45 36 16 8 70 27 45 32 14 7 60 27 60 32 12 6 70 27 60 32 A B C D E MM Speeds Gear Position...

Page 38: ...ose edge is too thin dulls quickly even when cutting comparatively soft materials This explain why in Figure 8 1 the knife edge breaks off almost upon contact with the metal while the more obtuse cutting edge of a cold chisel stands up to continuous pounding Figure 8 1 The knife edge breaks off almost upon contact with the metal because its cutting edge is not as strong as that of a cold chisel Th...

Page 39: ... angle often increases the cutting tool s efficiency by increasing its wedging action Cutter shape is usually more important than edges which generally are rough ground and require honing for fine finishing cuts or work in soft ductile materials like brass or aluminum Lack of clearance which lets a tool drag on the work below the cutting edge is a break on the lathe greatly reducing pressure on th...

Page 40: ...t and lathe speed low dipping a brush in oil occasionally and holding it against the workpiece will provide sufficient lubrication For continuous high speed heavy duty production work however especially on tough alloy steels using a cutting oil or coolant will increase cutting efficiency It s essential if you re using a non HSS cutting tool When you use coolant direct it against the cutting point ...

Page 41: ... Figure 8 3 is 300 Then rpm 300 sfm x 4 1 rpm 1200 1 rpm 1200 or next slower speed For high carbon steel also 1 in diameter rpm 50 sfm x 4 1 rpm 200 1 rpm 200 or next slower speed With the four turret toolpost you can install all standard shaped turning and facing tools with 1 on smaller shanks The centerline is approximately 5 8 above the bottom of the turret Smithy also offers quick change tool ...

Page 42: ...ng form the correct or most convenient shape for a specific operation Front clearance away from the toolpoint Clearance away from the side of the tool side rake Free chip movement over the tool and away from the cutting edge Keenness angles can vary from 60 for mild softness to 90 for hard steels and castings Figure 9 1 Figure 9 1 Keenness angles vary from 60 to 80 degrees Front clearance must alw...

Page 43: ...grind the right side clearance 3 grind the end form or radius 4 grind the end clearance 5 grind the top rake touching in a chipbreaker If you are honing the cutting edge for fine finishing or machining soft materials draw the cutter away from the cutting edge across the oilstone as shown in figure 9 4 Figure 9 3 Grinding sequence for an unground cutter bit Grinding Wheel Cutter Bit 1 Left Side Cle...

Page 44: ...l the keener the angle of the cutting edge For soft steels angles as acute as 61 are possible Figure 9 5 Figure 9 5 With soft steels 61 degree angles are possible The same general rule applies to cast iron Chilled or very hard cast iron requires tools with cutting edge angles as great as 85 For ordinary cast iron you obtain greatest efficiency with a more acute cutting edge approximately 71 Figure...

Page 45: ...utting edge This serves as a chip guide and starts the chip curling smoothly Figure 9 7 Figure 9 7 A crater starts the chip curling smoothly Using a Center Gauge to Check V Thread Forms It may be convenient to grind a standard cutter bit for thread cutting especially for cutting standard 60 V threads When grinding an ordinary square cutter into a thread cutting tool take care to ensure a true thre...

Page 46: ...file Carbide Tipped Cutters and Cutter Forms Carbide is a compound of carbon and a metal In cutting tools it is usually carbon and tungsten The hardness of carbide cutting materials approaches that of diamond While carbides permit easy machining of chilled cast iron hard and tough steels hard rubber Bakelite glass and other difficult or unmachinable materials its primary use in industry is for lon...

Page 47: ...tallic high temperature alloys General purpose C 2 200 and 300 Series stainless steels Light finishing Precision boring Roughing cuts General Purpose C 3 C 4 C 5 C 6 Alloy steels Finishing cuts C 7 400 Series stainless steel high velocity Precision boring C 8 9 6 Or Visit www smithy com Grinding Cutter Bits for Lathe Tools ...

Page 48: ...together The cutting edge on the tool should meet the point on the center It may be necessary to use shims which can be of various thicknesses and materials Figure 10 1 Many seasoned cutting tool height machinists use pieces of old hacksaw blades as shims If the toolbit is too high shim the back of the toolbit If it s too low shim the entire tool Figure 10 1 Placing shims under the tool can correc...

Page 49: ...rk use a straight shanked tool held perpendicular to the line of lathe centers in the right side of the toolpost The tool will tend to swing out of the cut rather than hog into the work if you reach a stalling point Figure 10 3 Figure 10 3 The tool will swing out of the cut left rather than hog into the work right if you reach a stalling point Note the tool is in the right hand side of the toolpos...

Page 50: ...r cutting efficiency position the bar while parallel to the line of lathe centers sufficiently below center to give the cutter a 14 1 2 degree approach angle For internal threading grind the top face of the cutter to compensate for this angle giving a flat true form top face Some machinists prefer to position the tool slightly above center when boring With the bit above center if a tool chatters i...

Page 51: ...Your machining accuracy depends primarily on how precisely you locate these holes at the center of the bar or block Locating these holes is called centering Centering You can improve centering greatly by first squaring or facing the ends of the workpiece Section 13 1 This gives you a true cross section in which to locate the centering holes 1 First chuck the stock in the appropriate chuck Let the ...

Page 52: ...he center Figure 11 4 Figure 11 2 Centering on round stock and Figure 11 4 Centering on square or rectangular stock Figure11 3 Use centering instruments include calipers and dividers 2 After locating the center of each end drive a starting depression for the drill into the stock with a center punch 3 Check centering accuracy by placing the workpiece between the spindle and tailstock centers 4 Revo...

Page 53: ...eter ground to a 60 point A 60 taper is standard for lathe center points Correct center depth is given in Figure 11 6 Take care to get an accurate 60 countersink in the center Figure 11 7 Figure 11 6 The correct depth of center is illustrated above If it s too deep bottom only sharp outer edges will contact the center Figure 11 7 Counterbore centers with a drill to a 60 point so they fit the lathe...

Page 54: ...properly made clamp dog the under face of the heads of tightening screws are convex and fit into concave seats while the holes in the upper bar are elongated This design allows a firm grip of off square shapes without bending the screws Top and bottom bars should also have V notches to give a firm grip on triangular or other odd shaped stock You can use clamp dogs or special V jaw dogs also to hol...

Page 55: ...liminate side play but not so tightly they bind If you re working on a long workpiece check it frequently to be sure the center does not bind Also balance unbalanced setups with counterweights to overcome any throw as the work revolves Figure 11 11 Figure11 10 Make sure the lathe dog tail is free in the faceplate slot so it won t lift off the true line of centers Figure 11 11 Counterweights can he...

Page 56: ...nting Figure 11 13 Mandrels with compressible ends for holding single or ganged pieces are also available When a workpiece is mounted on a mandrel machine it as you would a solid shaft You can drill eccentric centers in mandrel ends to permit eccentric turning Figure 11 12 Mount workpieces too long for of the lathe centers Figure 11 13 Hardened steel mandrels have a slight ground taper and expandi...

Page 57: ...faces and boring will be untrue The tips of the jaws are bronze and require lubrication Figure 11 14 Steady rests mount on the lathe bed and provide three bearing surfaces Follow Rests Long or slender shafts that are apt to spring out of have a slight ground taper and alignment by the thrust of the cutting tool often require a follow rest expanding collar Figure 11 15 Follow rests mount on the car...

Page 58: ...universal geared scroll chuck holds only round or near round work with three six nine 12 or other multiple numbered sides It always holds work concentrically The three jaw chuck has the advantage of being self centering all jaws move in or out together Figure 11 17 Figure 11 16 Four jaw independent lathe chucks hold round square eccentric or odd shaped workpieces Figure 11 17 Three jaw universal g...

Page 59: ...ped workpieces For greater accuracy after roughly centering the stock using chalk set a dial indicator at the back of and square to the stock Make sure you can see it clearly Rotate the chuck by hand Looking at two opposing jaws determine which side is higher Align the higher side with the dial indicator loosen the opposite jaw and tighten the higher jaw Do the same with the other two jaws Repeat ...

Page 60: ...hucks the key moves all the jaws at once You need not center or check for concentricity because these chucks center automatically Jaws are not reversible Each chuck comes with two sets of jaws One is for setups with high steps toward the inside inside jaws the other for mounting in the chuck with high steps to the outside outside jaws When installing the chuck jaws on a three jaw chuck install the...

Page 61: ... small diameter work They are housed within the spindle nose for maximum tool clearance making it possible to machine thread or cut off close to the spindle While chucks are universal tools that hold a range of stock sizes and shapes collets are special tools There is a collet for every size and shape of workpiece Made with extreme accuracy hardened and ground standard split collets are slotted so...

Page 62: ...ou would any other cutting tool Toolpost grinders come with wheels of different shapes sizes and grits for grinding different materials and surfaces They also come with arbors and mounted wheels for grinding internal surfaces You can use them to grind or polish surfaces to grind lathe centers arbors taper sockets leader pins gauges valve seats and other close fitting parts and to sharpen tools 11 ...

Page 63: ...10 1 Figure 12 1 Place a cutter into the left side of the turret 3 With the tool properly positioned tighten the Allen capscrew 4 Next run the carriage to the right end of the workpiece with the crank Make sure the lathe is set to feed toward the headstock 5 Now determine the depth of the cut Move the tool to the desired depth till it just touches the stock and zero the cross feed dial 6 Start the...

Page 64: ...ish Turning 1 After you have rough turned the workpiece to approximate finished size within 1 32 replace your cutter bit with a freshly ground keen edge cutter 2 Make one or more light finishing cuts across the machined surface 3 Check the diameters carefully with a calliper or micrometer to be sure you are working to proper dimensions Remember the diameter will reduce twice the thickness of the c...

Page 65: ... smooth polished surface free of machine marks You ll obtain the best results with a toolpost grinder If you don t have one use a file With a file take full biting strokes across the revolving workpiece at a slightly oblique angle Do not drag the file back across the workpiece instead lift it clear for each return stroke Use a clean dry file and keep the workpiece clean as well Wipe the workpiece ...

Page 66: ...tailstock In both methods the cutter must engage the work on dead center if the taper is to be accurate Compound Rest Tapers cut with the compound rest are usually short abrupt angles such as centers bevel gear blanks and die parts Figure 12 6 In general these are not considered taper turning which applies to machining longer more gradual tapers Setting over the tailstock Cuttting tapers by settin...

Page 67: ... set over needed to machine any given taper depends on three factors The differential between the finished diameters of the extreme ends of the taper The length of the taper in relation to its extreme diameters if the entire shaft is to be tapered The ratio between the length of the shaft or work between centers when you re tapering only part of the shaft When the taper extends the entire length o...

Page 68: ...t all dimensions to inches B Be sure to zero the tailstock before resuming straight turning Boring a Tapered Hole Boring a tapered hole involves setting the compound at the desired degree of taper and feeding the tool with the compound rest Make sure the compound rest is set at half the degrees of the angle of the completed taper hole You can also use a taper attachment to bore a tapered hole 12 6...

Page 69: ...ng it protrude about an inch Place a right hand side tool or a straight turning tool with a facing cutter in the toolpost Carefully adjust the cutting edge so it is exactly on center then tighten it into the toolpost If you don t do this a small tit or projection will remain in the center of the stock and perhaps cause the center drill to run off center Start your lathe on the slowest speed Bring ...

Page 70: ...ressing and raising the surface of the metal into a pattern As with all other forming operations your work can be no better than the pattern your knurling no better than the knurls Be sure the knurls are sharp clean cut preferably hob cut and properly hardened To make a true uniform knurl maintain uniform pressure on both knurls Select a self centering knurling tool that equalizes pressure on the ...

Page 71: ...ine force the tool into the work another 1 64 reverse the lathe without removing the tool and feed it back to the starting point Feed both ways using the automatic longitudinal feed Once across each way usually makes a good knurl Figure 13 3 Feed the knurling tool at a slight angle off from perpendicular to the line of the work piece 13 3 Or Visit www smithy com Lathe Facing and Knurling ...

Page 72: ...ent Figure 14 1 Remove all C clips nuts and gears 2 Select the proper A D gear combination from the list outside the pulley box door 3 Use the Allen wrench to loosen the bolt at the bottom of the bracket assembly for full swing and easy gear replacement Figure 14 1 4 Place the selected D gear on the D shaft flange side in Replace the spacer washer and nut 5 Place the selected C gear flange side in...

Page 73: ...until the A and B gears mesh Hold the bracket assembly in place and tighten the bolt Make sure the gears turn smoothly before engaging the powerfeed You may need to make some adjustments 10 Engage the E gear between the C and D gears to reverse the leadscrew Figure 14 3 Figure 14 3 Engage the E gear between the C and D gears to reverse the leadscrew Changing Gears 14 2 Or Visit www smithy com ...

Page 74: ...s You may cut coarse or fine threads in a great range of threads per inch in V or square shapes in established profiles like Unified National acme and metric You can cut single threads or multiple threads that run concurrently along the shaft You determine the type of thread by how you ll use the screw Each thread form requires a different shaped tool to cut or chase it Beginners will use the Unif...

Page 75: ...rd or shim between the cutter point and workpiece Figure 15 1 When the tool is on dead center the card or shim will remain vertical With a credit card there is no possibility of chipping the cutter as the workpiece and cutter come together Figure 15 1 Check dead center with a credit card Set the compound perpendicular to the line of centers and rotate it 29 1 2 degree to the right Figure 15 2 Plac...

Page 76: ...o apply the appropriate cutting fluid to the workpiece Feed the cross slide in 0 005 0 020 for the first run depending on the pitch of the thread you have to cut If you are cutting a coarse thread start by taking a few heavy cuts Reduce the cut depth for each run until it is about 0 002 at the final run Zero the cross feed calibration and make the second cut Continue this process until the tool is...

Page 77: ... except increase the lead to make room for succeeding threads a double lead for a double thread a triple lead for a triple thread etc After completing the first thread remove the work from the centers without loosening the lathe dog Then put it back in the lathe with the tail of the lathe dog in the correct slot to index the work for the next thread This work requires a faceplate with accurately p...

Page 78: ...ck in the centers exactly where it had been Then remove the hips and test again Repeat until are finished Finishing Off a Threaded End After cutting a thread and before removing the threading tool chamfer the end This improves its appearance and removes sharp corners and burrs It also aids the screws as it engages a nut or threaded hole Cutting Threads on a Taper Cut threads on a taper the same as...

Page 79: ...r the drill the greater the number of peripheral feet cut per revolution That is why you should use a slower drilling speed If no drilling speed data are available it s generally safe to run drills under 1 4 diameter at up to 750 rpm and drills up to 1 2 diameter at 500 rpm with larger drills at proportionately slower speeds With the workpiece in the headstock and the drill in the tailstock chuck ...

Page 80: ... have only one cutting edge There are double end cutters however and they offer advantages in special instances In grinding cutters allow sufficient end rake to provide clearance from the internal diameter Figure 16 2 A tool with a smooth ended bar won t mark the workpiece Except with cored castings pipes or tubing begin by drilling a hole large enough to admit the end of the boring bar Because th...

Page 81: ...fore more rigidly if it s at a 90 angle to the bar For machining ends of a bar however you need a boring bar that holds the cutter at an angle or angles so the cutter extends beyond the end of the bar Figure 16 5 For maximum visibility position the cutting edge at the near side parallel to the centerline The rules that apply to external turning apply to boring as well except as noted earlier where...

Page 82: ...with external thread cutting the internal threading tool must engage the work on dead center and be held so the cutter coincides with the workpiece s center radius In squaring the cutter with the work use a center gauge Figure 16 6 or thread gauge Internal cutters require greater end and side clearance and cutter length is also restricted because internal thread cutters must have enough end cleara...

Page 83: ...l the thread forms used for external threads There is only one factor that calls for special attention in cutting special shaped internal threads the difference of clearances between the nut and screw recommended for different thread types Figure 16 8 If you don t have recommended clearances it is safe to cut a nut thread internal thread 0 005 to 0 010 per inch larger in the screws outside diamete...

Page 84: ...he workpiece as possible with the top of the blade on dead center and exactly perpendicular to the line of centers Extend the blade only far enough to pass through the work piece just beyond its center The tool should feed to the workpiece on exact center slowly and evenly with the cross feed If the tool hogs in and the spindle stops rotating turn off the motor and reverse the spindle by hand befo...

Page 85: ...ad Figure 5 1 rotates horizontally and moves vertically A quill that moves in and out of the head carries the spindle You can move the table horizontally in two directions by turning the cross slide and leadscrew handwheels Figure 5 1 The cross slide handwheel turns the table longitudinally at right angles to the spindle axis the long feed hand crank moves it transversely parallel to the spindle a...

Page 86: ... the width of the vise jaw in inches or millimeters Plain and swivel vises range from 3 to 10 76 to 254 mm Tilting and universal vises range from 3 4 to 5 76 102 mm to 127 mm The bases of many vises are fitted with keys small steel blocks that fit into the milling table T slot for quick alignment of the vise Before mounting a vise make sure the bottom is clean and smooth If there are any nicks or ...

Page 87: ...turn the workpiece a certain number of degrees you can make cuts at different angles This is how to cut gears Figure 19 2 A chuck attaches to the spindle face of a dividing head Rotary Tables A rotary table Figure 19 3 is a precision worm and wheel unit that lets you cut gears precision holes and curved slots Rotary tables mount vertically or horizontally to the table T slots secure the work piece...

Page 88: ... of your arbors Store them in a rack or bin If you won t be using them for several days or longer oil them to prevent rusting especially in damp weather Collets and Holders Straight shank end mills fit into spring collets Figure 20 2 or end mill holders Figure 20 3 Their precision ground shanks go into the mill spindle When you tighten a spring collet its hole reduces and the collets grips the end...

Page 89: ...ll out of the spindle when the drawbar is removed 4 Unscrew the drawbar and remove the arbour or adapter 5 Your machine includes a tapered drift for removing tapers Follow these steps 6 Remove the drawbar 7 Extend the mill spindle to expose the outer taper drift slot 8 Rotate the spindle to align outer and inner taper drift slots You will be able to see the end of the adapter through both slots 9 ...

Page 90: ... Solid end mills have straight or tapered shanks shell end mill adapters have tapered shanks End mills machine horizontal vertical angular or irregular surfaces in making slots keyways pockets shoulders and flat surfaces Two flute or center cutting end mills Figure 21 1 have two teeth that cut to the center of the mill They may feed into the work like a drill called plunge milling then go lengthwi...

Page 91: ... side mill finish up with the T slot cutter Keyseat cutters cut keyseats for Woodruff keys shaped like a half circle Shell end mills Figure 21 3 which mill wide flat surfaces have a hole for mounting on a short arbor The center of the shell is recessed to provide space fro screw or nut that fastens the cutter to the arbor The teeth are usually helical and diameters are as large as 6 Figure 21 3 Sh...

Page 92: ... Milling Cutters Similar to plain milling cutters side milling cutters also have teeth on one or both sides Figure 21 4 The teeth on the periphery do most of the cutting those on the sides finish the side of the cut to size They cut grooves or slots and often work with other cutters to mill special shapes in one operation Figure 21 4 Side milling cutters are similar to plain milling cutter but the...

Page 93: ... come as single and double angle cutters Single angle cutters have one angular surface Teeth are on the angular surface and the straight side and they usually have 45 or 60 angles Double angle cutters machine V grooves Those with equal angles on both faces usually have an included angle of 45 60 or 90 Form Relieved Cutters Formed tooth cutters machine surfaces with curved outlines You can sharpen ...

Page 94: ...od or as a mist We recommend cutting fluids for steel aluminum and copper alloys With cast iron and steel however they tend to reduce the life of carbide tools leaving tiny cracks along the cutting edge Follow the advice of tool manufacturers to avoid tool failure Materials such as cast iron brass and plastics are often machined dry You can use compressed air to cool tools and clear chips away Whe...

Page 95: ...imary clearance The angle between the back of the land and the heel of the tooth is the secondary clearance Check both clearances and the rake Some cutters are sharpened on the periphery by grinding the land at a suitable angle They include cutters with straight or spiral teeth angular cutters side milling cutters face mills end mills and reamers You sharpen others by grinding the front faces of t...

Page 96: ...pi 3 14 You can use an rpm chart for selected diameters of cutting tools at different cutting speeds To change speeds set the belts according to Figure 6 12 Feeds Set the direction of feed before you begin milling Up milling or conventional milling is when the direction of feed is opposite to the direction of cutter rotation Figure 22 2 Down milling or climb milling is when the direction of feed i...

Page 97: ...ials require lower feed rates than softer materials Feed wider deeper cuts more slowly than narrow shallow cuts A slower feed rate gives a better surface finish Never stop the feed before finishing the cut If you know the feed in inches per tooth use this formula to calculate table feed rate in inches per minute ipm Ipm ipt x N x rpm Where ipt inches per tooth N number of teeth in the milling cutt...

Page 98: ...80 140 60 110 250 500 225 400 Plain high carbon steels 1060 1095 125 175 175 225 70 120 60 110 250 450 225 400 Tool Steels W1 W7 H20 H43 D1 D7 150 200 200 250 200 250 80 120 40 85 30 60 300 350 175 300 100 200 Stainless Steel 302 430F 135 185 135 185 70 100 100 140 225 350 350 450 Gray Cast Iron ASTM Class 20 Through Scale Under Scale 110 160 140 200 130 225 350 700 400 800 Aluminum Cold drawn wro...

Page 99: ...e periphery of the cutter removes a chip every revolution Milling wide flat surfaces this way is called slab milling Figure 23 1 One way to mill a flat surface is by plane milling Another way to mill flat surfaces is by face milling In this method the cutter teeth operate at right angles to the cutter axis Inserted tooth face milling cutters Figure 23 2 face mill large surfaces Figure 23 2 Inserte...

Page 100: ... mill If you want to remove a lot of material use a roughing end mill first then finish to size with a regular end mill Plunge cutting is efficient for removing material quickly on low horsepower Plunge the end mill a predetermined width and depth retract it then advance and plunge it again repeatedly The maximum cutting force is in the machine s strongest axial direction Milling a Cavity After la...

Page 101: ...n top of the support column Figure 24 1 To raise the bevel gear loosen the three screws with heads and tighten the three without heads To lower the bevel gear loosen the three screws without heads and tighten the three with heads When you are done make sure all six screws are tight Figure 24 1 Use the six screws on top of the millhead support column to adjust the bevel gear To replace the bevel ge...

Page 102: ...vy grease or Cosmo line on the back of the key it will stay in place when you insert it If you use your finger to put it into place put a bit of the grease on your finger 24 3 Lathe Mill clutch If the lathe clutch drop into neutral while turning there will be too much gap between the jaws of the clutch You must first determine how much gap there is A spring loaded steel ball in a detent in the jaw...

Page 103: ...hich keyway it is in Remove the shaft sleeve from the spindle Figure 24 6 shorten the sleeve by amount of gap and reassemble the entire unit The left jaw clutch will now slide on further eliminating excess gap between the jaws Figure 24 4 Bend back the tab on the lockwasher and remove the spanner nut and lockwasher Figure 24 5 Pull on the clutch sleeve to remove the left jaw clutch and entire clut...

Page 104: ...f needed Tools not mounted tightly in post Remount tools Cross slide gibs to bed and base loose Adjust gibs Gibs in toolpost loose Adjust gibs in toolpost Tool turret not tight Tighten toolpost Feed rate too fast Install correct gears Gears loose Tighten gears and posts Thread is not smooth Cause Solution Too dull Sharpen tool Tool not centered Center tool Tools not mounted tight in post Remount t...

Page 105: ...nt in cross slide table Cause Solution Carriage gib improperly adjusted Adjust carriage gib Table gib improperly adjusted Adjust table gib Carriage moves smoothly in only one direction Cause Solution Debris on way or gib Remove debris Burr on gib Remove burr with fine file Gib improperly tensioned Loosen gib and re tension One or more wipers mounted too low Reposition wiper s Cross slide handwheel...

Page 106: ...l Sharpen or replace tool Tool not ground properly Regrind tool Tool at wrong angle Correct tool position Tools not held tightly Tighten toolholder Wrong cutter for material Use correct cutter Cutting speed incorrect Increase or reduce speed Work has unwanted taper Cause Solution Work improperly aligned Realign centers on work Debris in spindle setup or tools Clean and reset setup work or tool Off...

Page 107: ... Too much flex in compound rest Tighten gibs clean ways cross slide or carriage Too much backlash in the compound Cause Solution Loose spanner nuts Tighten spanner nuts Worn nut Replace nut Machine slings oil from behind the chuck or in belt box Cause Solution Oil reservoir overfilled Check oil level Worn oil seal Replace felt in seal Milling Tool chatters Cause Solution Gibs too loose on cross sl...

Page 108: ...awbar not secured Tighten drawbar Debris on spindle Clean debris and arbour and remount tool Bearing loose or worn Tighten or replace bearings Cutting too fast Reduce speed Incorrect bit Use correct bit Entrance hole is out of round Cause Solution Bit dull Use sharp bits Incorrect drill bit Use correct bit Bit turns erratically or stops Cause Solution Bit fed into work too fast Reduce feed rate Be...

Page 109: ...lectrical connections Tighten wiring connections Motor and pulleys turn but not lathe or mill Cause Solution Lathe mill clutch is in neutral Pull the clutch sleeve all the way out lathe or push it all the way in mill Pulleys turn and clutch is engaged but the mill does not turn Cause Solution T key missing Replace key Bevel gears stripped or broken Replace bevel gear Bevel gear out of adjustment R...

Page 110: ...l Calibration on Leadscrew 002 Dial Calibration on Longfeed Rack N A Dial Calibration on Tailstock 002 Feed Rates 003 006 X axis Headstock Taper MT4 Lathe Chuck Bore 1 17 Lathe Chuck Diameter 5 Lathe Chuck Max diameter work piece 5 Lathe Chuck Min diameter work piece 1 8 Lathe Chuck Mount Bolt On Lathe Chuck Type 3 Jaw Self Centering Spindle Bore 1 03 Spindle Speeds Six 160 1600 RPM Swing Over Bed...

Page 111: ...ead Rotation 360 Degrees Head Travel 3 1 4 Quill Diameter 2 3 4 Quill Travel 3 5 8 Spindle Center to Front of Chuck 3 3 16 Spindle Center to Lathe Spindle Flange 5 1 2 Spindle Center to Support Column 6 7 8 Spindle to Table Distance min max 6 1 4 13 Spindle Speeds 12 125 1600 rpm Spindle Taper MT3 Tool Size Limits 1 X Axis Travel 6 5 8 Y Axis Travel 7 3 8 Electrical Amperage 11 amps Horsepower 3 4...

Page 112: ... the toothed rack on the front of the machine and let the entire carriage to move freely left and right 6 The apron will not drop down far enough to come free from the carriage because of the two taper pins that would go through the carriage inot the apron 7 Loosen the two carriage gib adjustment screws to allow easier removal of the carriage With the assistance of a helper slide the carriage tabl...

Page 113: ... 2 geears ontoo the 28 gearshaft 3 Remove setscrew 32 that locks the 28 shaft into the main casting 24 4 Drive the 28 gearshaft out from the front to back Assembly Procedure 1 Coat all moving parts with a liberal amount of a medium weight grease such as Lubraplate 2 Make sure the key 27 is in the gearshaft 28 Slide the shaft into the apron while installing gears 29 30 and 25 as the shaft is slid i...

Page 114: ...rol systems for a period of one 1 year to the original purchaser from the date of purchase If within one 1 year form the date of purchase a SmithyCNC machine and or control system fails due to defect in material or workmanship SmithyCNC will at their choice repair and or replace components with new or remanufactured parts free of charge Some have asked why SmithyCNC machines have a shorter warrant...

Page 115: ... are hereby limited to the duration of this written warranty This warranty gives you specific legal rights and you may also have other rights which vary from state to state Some states do not allow the exclusion or limitation of incidental or consequential damages so the above limitation or exclusions may not apply to you Telephone Support Service engineers are available 8 am to 5 pm EST Service a...

Reviews: