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    MIDAS 1220 LTDCOMBINATION LATHE/MILL/DRILLOPERATOR’S MANUALUpdated July, 2008170 Aprill Dr., Ann Arbor, MI, USA 48103 Toll Free 1-800-476-4849www.smithy.com

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    ©2008 Smithy Co. All rights reserved (Revision 1).170 Aprill Dr., Ann Arbor, Michigan, USA 48103 Toll Free Hotline: 1-800-476-4849 Fax: 1-800-431-8892 International: 734-913-6700 International Fax: 734-913-6663 All images shown are from Midas 1220 LTD machine.All rights reserved. No part of this...

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    Table of ContentsInventory Check ListItems mounted to your machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iItems packed in the larger Smithy box . . . . . . . . . . . . . . . . . . . . . . . . . .iItems packed in smaller Smity box . . . . . . . . . . . . . . . . . . . . . . ...

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    Lathe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7Adjusting Gibs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7Reducing Backlash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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    Setting Up Work in a Chuck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10-7Mounting Work in a Four-Jaw IndependentLathe Chuck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10-8Mouting Work in a Three-Jaw Universal Chuck . . . . . . .10-9Toolpost G...

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    Chapter 17: MillingMilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17-1Holding Milling Cutters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17-2Arbors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

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    Inventory Check ListIt is a good idea to take inventory of the parts of your machine soon after it is unpacked.By doing so, you can quickly determine if any parts are missing. In addition, should youfind it necessary to return the machine to Smithy for any reason, the inventory will ensurethat al...

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    K Oil CanPart # 80-100Quantity 1 K 7/16” T-Slot NutsPart # 35-105Quantity 2 K Vise, 0-90º Adjustable AnglePart # 32-110Quantity 1 K End Mill, 4 FL HSS 1/4” w/3/8” ShankPart # 50-402Quantity 1 K End Mill, 4 FL HSS 3/8” w/3/8” ShankPart # 50-406Quantity 1K End Mill, 4 FL HSS 1/2” w/3...

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    K MT4 Dead CenterPart # 41-004Quantity 1 K 8/10 mm Open End WrenchPart # C30539Quantity 1 K 17/19 mm Open End WrenchPart # C30535Quantity 1 K Allen Wrench, 4 mmPart # C30540Quantity 1 K Allen Wrench, 5 mmPart # C30542Quantity 1 K Allen Wrench, 6 mmPart # C30537Quantity 1K Allen Wrench, 8 mmPart #...

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    Inventory ChecklistivOr Visit www.smithy.comK Gear,45 TeethPart # C30156Quantity 1K Gear,48 TeethPart # C30151Quantity 1K Gear,49 TeethPart # C30152 Quantity 1K Gear,50 TeethPart # C30153 Quantity 1K Gear,56 TeethPart # C30157Quantity 1K Gear,60 TeethPart # C30159Quantity 1K Gear,63 TeethPart # C...

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    Midas 1220 LTD Operator’s ManualvFor Assistance: Call Toll Free 1-800-476-4849Missing Items?If you find that an item is missing or defective from your Quick Start Tool PackCall Us TOLL FREE 1-800-476-4849 or send an e-mail to info@smithy.comwithin 30 days of receiving your machine so that we ma...

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    Chapter 1IntroductionCongratulations on purchasing a Smithy lathe-mill-drill. We are pleased you chose Smithyto fulfill your machining needs.The purpose of this manual is to give the machinist, beginning or advanced, theinformation he need to operate the Smithy Midas 1220 LTD. It will teach you ...

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    Chapter 2SafetyYour workshop is only as safe as you make it. Take responsibility for the safety of all whouse or visit it. This list of rules is by no means complete, and remember that commonsense is a must. 1.Know your machine. Read this manual thoroughly before attempting to operate yourmachine...

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    13.Use the correct tool for the job. Don’t try to make a tool into something it isn’t.14.Keep your mind on your work. Pay attention to these simple rules and you will spendmany safe, enjoyable houses in your workshop.Note:Your safety depends largely on your practices.2: Safety2-2Or Visit www....

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    Chapter 3Caring For Your MachineYour machine is a delicate, precision tool with hardened ways and hand-scraped bearingsurfaces under the table and carriage. Any rust spot or battering of the ways, any chipsor grit between close-fitting parts, will affect the accuracy of this fine tool. Follow the...

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    Chapter 4Basic Parts of the MI-1220 LTDLearn the operation of your machine, you have to know the names and functions of itsbasic units.Figure 4.1 Midas 1220 LTD1. Bed.The bed is the machine’s foundation. It is heavy, strong, and built for absoluterigidity. The two ways on the top are the tracks...

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    3. Compound Rest.Mounted on the cross slide, the compound rest swivels to any anglehorizontal to the lathe axis to produce bevels and tapers. Cutting tools fasten to atoolpost on the compound rest. The calibration on the front of the base are numbered indegrees from 60 right to 60 left.4. Cross S...

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    14. Half-nut Lever.This lever transmits power to the carriage for threading.15. Power Longitudinal Feed.Push the lever down to engage the power of the long feedfor general cutting.16. Power Cross Feed.Push the lever down to engage the cross feed and pull it up todisengage.17. Powerfeed Speed Sele...

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    Chapter 5Uncrating and Setting Up the MI-1220 LTDMoving the MachineMoving a machine tool can be dangerous. Improper techniques and methods may injureyou and/or damage the machine. To find a professional to move and site your Smithymachine, look in your local Yellow Pages under “Machine Tools, M...

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    CautionThe cut edges are sharp. The bands secure the crate top to the base.After removing the straps, lift off the crate top. Tip the crate from the tailstock end upand over the machine (Figure 5.1). Do not damage the crate. You may need it anothertime to transport the machine.Once your crate cov...

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    Three-Jaw Chuck1.Remove the three bolts behind the chuck that hold it to the spindle flange (Figure 5.2).The chuck will come off. Don’t let it fall onto the ways. Placing a board between the chuckand ways will protect the ways.Place the machine on a strong, rigid table 40” long, 24” wide an...

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    Cleaning and Lubricating the MI-1220 LTDSmithy machines are shipped with protective grease coating called cosmoline. UseWD-40 or non-corrosive kerosene to remove the cosmoline.Once you have your MI-1220 LTD set up and positioned correctly, you are ready forlubricating. You must do this carefully ...

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    Open the gearbox door to expose the pick-off gears. Oil the button in the casting behindthe D gear. Then put a few drops of oil on the teeth of all the gears. Grease the zerk onthe A gear shaft.Check the sight glass under the chuck. If necessary, add oil until it is half full. The oil fillplug is...

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    Put oil on the button at the back of the cross slide.Oiling the LeadscrewPut oil in the oil buttons on the left trestle.Put oil in the support for the right end of the leadscrew.Oiling the TailstockFigure 5.9 Oil the two buttons on the top of the tailstock.Oil the buttons on top of the tailstock....

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    Adjusting Belt TensionThe MI-1220 LTD has two belt tensionersinstalled by the factory. One for themillhead and the other one for the pulleybox.MillLocate the “L shaped” lever and a thumbscrew at the top of the mill motor. Loosen thethumbscrew and then rotate the lever to increase or decrease ...

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    Reducing BacklashBacklash of 0.008-0.015” as measured on the dial is normal. If you have more backlashthan that in your crossfeed table, refer to the schematics at the back of this manual, ifnecessary and follow these directions:1.Tighten the cap nut in the center of the cross feed hand wheel s...

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    4.Start the mill motor by pushing in the green start button. After a few minutes, push inthe red stop button and allow the motor to stop. Flip the yellow switch cover and switchit to the opposite position and repeat the above procedure.5.Start the lathe by pushing the green button on the lathe c...

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    Setting Lathe and Mill Speeds for the MI-1220 LTDFigure 5.14 Setting Lathe Speeds (RPM)Changing belts changes lathe speeds. The lower speeds use the two short belts. There isonly one position for the motor pulley to idler pulley belt. It goes on the smallest sheaveof the motor pulley (behind the ...

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    Chapter 6TurningThe lathe rotates a workpiece against a cutting edge. With its versatility and numerousattachments, accessories, and cutting tools, it can do almost any machining operation. The modern lathe offers the following: • The strength to cut hard, tough materials • The means to hold ...

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    The lathe spindle holding the workpiece revolves at a selected speed (revolutions perminute, or rpm) according to the type and size of the workpiece. The leadscrew, whichruns the length of the lathe bed, also revolves at the desired rpm. There is a definite andchangeable ratio between spindle and...

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    • The means to hold the cutting point tight • The means to regulate operating speed • The means to feed the tool into or across, or into and across, the work, eithermanually or by engine power, under precise control • The means to maintain a predetermined ratio between the rates of rotati...

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    Chapter 7Metal TheoryTool sharpnessInstead of being the all-important factor in determining tool performance, keenness ofthe cutting edge is just one of many factors. On rough or heavy cuts, it is far lessimportant than strength, because a false cutting edge or crust usually builds up on thetool ...

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    Table 7.1 Cutting Speeds and Feeds for High-Speed-Steel ToolsIn everyday lathe operations like thread cutting and knurling, always use cutting oil orother lubricant. On such work, especially if the cut is light and lathe speed low, dippinga brush in oil occasionally and holding it against the wor...

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    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. The four-turret toolpost lets you mount up to four different tools at the same time. Youcan install all standard-shaped turning and facing tools wit...

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    Chapter 8Grinding Cutter Bits for Lathe ToolsHigh Speed Steel Cutters The advantage of HSS cutter bits is you can shape them to exact specifications throughgrinding. This lets you grind a stock shape into any form. Stock shapes come in anassortment of types, including squares, flats, and bevels. ...

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    Front clearance must always be sufficient to clear the work. If it is too great, however,the edge weakens and breaks off (Figure 8.2). Side and back-rake requirements vary withthe material used and operation performed. Back rake is important to smooth chip flow,which is needed for a uniform chip ...

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    Figure 8.4 When honing, draw the cutter away from the cutting edge across the oilstone.Materials Other Than Steel As pointed out earlier, when grinding HSS cutters, we determine cutting angles primarilyby strength requirements, not keenness requirements. Angles and rakes for generalindustrial sho...

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    gain greater angle keenness only in increased side and end rakes. It is often advisable tohone the cutting edges of cutters used to machine brass. Note:All roundnose cutters are ground with flat tops and equal side rakes because theyare fed across the work, to both right and left.Special Chip Cra...

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    Acme or Other Special Threads Thread gauges are available for all standard threads. Before grinding such cutters,ascertain the correct pitch angle of the particular thread profile. For example, the pitchof an acme thread is 29° to a side, and the toolpoint is ground back square to an exactthread...

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    Chapter 9Setting Up Lathe ToolsAfter selecting a cutter, insert it in the toolholder. Allow the cutter bit to project justenough to provide the necessary clearance for the cutting point. The closer the cutter isto the toolpost, the more rigid the cutting edge. Allen-head capscrews hold the tool i...

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    Figure 9.2 The harder the steel (left),the less above center you set the cutter point.For soft brass and aluminum (right), set the cutter on dead center.When cutting toward the headstock on most turning and threading operations, swing thecompound rest to hold the shank of the toolholder at an ang...

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    Cutoff, Thread Cutting and Facing ToolsFor cutoff, thread cutting, and facing, feed the cutter to the work on dead center (Figure9.5). For the beginner, the average feed should not exceed 0.002 inches per revolution(ipr). Figure 9.5 Feed the cutter on dead center for cutoff, thread cutting and fa...

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    Chapter 10Setting Up with Centers, Collets, and ChucksBefore setting work up on centers, make sure the spindle and tailstock centers alignaccurately. Do this by inserting a center into the nose spindle and inserting the tailstockcenter into the tailstock ram. Then move the tailstock toward the he...

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    instruments (Figure 10.3). Centering square or rectangular stock is done by scribing linesfrom opposite corners. The intersection of these lines is the center (Figure 10.4).Figure 10.2 Centering on round stock and Figure 10.4 Centering on square or rectangular stock.Figure 10.3 Use centering inst...

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    If a combination drill is not available, you can drill centers with a small drill andcountersink them with a drill of sufficient diameter ground to a 60° point. A 60° taper isstandard for lathe center points. Correct center depth is given in Figure 10.6. Take careto get an accurate 60° counter...

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    Figure 10.8 Bolt the faceplate to the spindle flangeUsing a Clamp Dog Standard lathe dogs drive round, or near-round, shapes. Rectangular or near-rectangularstock requires clamp dogs. In a properly made clamp dog, the under face of the headsof tightening screws are convex and fit into concave sea...

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    Note:Before starting to machine work set up on centers, check to see the lathe dog tailis free in the faceplate slot so it won't lift stock off its true line of centers, as in Figure10.10. Also, be sure lathe centers fit closely into the center holes to eliminate side playbut not so tightly they ...

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    mandrel. When removing a mandrel, drive it back out of, instead of through, the hole.You can purchase hardened steel mandrels, which have a slight (0.003") ground taperand an expanding collar, to facilitate mounting and demounting (Figure 10.13). Mandrelswith compressible ends for holding si...

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    Figure 10.14 Steady rests mount on the lathe bed and provide three bearing surfacesFollow RestsLong or slender shafts that are apt to spring out of have a slight ground taper andalignment by the thrust of the cutting tool often require a follow rest expanding collar.Follow rests mount on the carr...

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    Figure 10.16 Four-jaw independent lathe chucks hold round, square, eccentric, or odd shaped workpieces. and Figure 10.17 Three-jaw universal geared scroll chucks hold round or near-round workpices.Mounting Work in a Four-jaw Independent Lathe Chuck For small-diameter, short work, insert jaws in ...

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    Figuere 10.18 For short, small-diameter workpieces, insert the jaws with high ends to the center.Figure 10.19 For large-diameter workpiecesinsert the jaws with high steps of the jaws to the outside.CautionNever leave the chuck key (wrench) in the chuck while the chuck is on the spindle. Anymoveme...

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    • When installing the chuck jaws on a three-jaw chuck, install them in numerical orderand counterclockwise rotation.Each jaw is stamped with a serial number and jaw number (#1, #2, or #3). The slots inthe chuck are not numbered, but there is a serial number stamped at the #1 slot (Figure10.20)....

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    Figure 10.22 Collet attachments are best for small-diameter work.• They are housed within the spindle nose for maximum tool clearance, making itpossible 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...

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    Chapter 11Lathe TurningRough TurningIn turning a shaft to size and shape where you have to cut away a lot of stock, take heavy,rough cuts to get the work done in the least time. With the MI-1220 LTD use a transversepowerfeed for heavy cuts-from right to left toward the headstock so the thrust is ...

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    For a screw to move, there must be some play in the thread. When backing the cuttingtool away from the cut, move the feedscrew enough to take up the backlash beforesetting the collar or when drawing the tool from the cut. Engage the longitudinal feed by moving the powerfeed engagement lever done....

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    Figure 11.2 You can do other turning cuts with different cutter bits and cutting tools.Machining Square Corners To machine an accurate corner, follow these steps:1.Set the compound rest perpendicular to the line of the centers and insert a right orleft-hand corner tool. 2.Using the longitudinal f...

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    stroke. Use a clean, dry file and keep the workpiece clean, as well. Wipe the workpiecedry and clean if you've used coolant or cutting oil. Never hold the file stationary while theworkpiece is revolving.Figure 11.3 With a file, take full strokes at an oblique angle; never hold the file still.For ...

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    To offset the tailstock, loosen the two base-locking bolts (Figure 4.8). To offset to theright, loosen the right adjusting bolt and tighten the left. To offset to the left, loosen theleft adjusting bolt and tighten the right.Figure 11.5 Tapers cut with the compound rest are usually short, abrupt ...

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    length of the portion to be tapered. Then multiply the resulting quotient by half thedifference between the extreme diameters of the finished taper.Figure 11.7 Tailstock setover should be half the difference between the finisheddiameters of the ends, or 0=T" x L"/2, where T= taper per i...

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    Chapter 12Lathe Facing and KnurlingBefore removing your work from the centers, face or square up the ends. On accuratework, especially where shoulders, bevels, and the like must be an accurate distance fromthe ends, do the facing before turning the shank. This also cleans the ends and machinesthe...

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    move the crossfeed lever down. Pull the lever up at the end of the cut to stop the cuttertravel.CautionRemember caution must be taken to not run the powerfeed past their limits of travel. As part of the normal operation, procedures, run each axis through the entire length of the proposed machinin...

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    Use plenty of oil, lubricating both knurl and workpiece. Then start the lathe and engagethe automatic feed, moving the knurls across the portion to be knurled. When you reachthe left scribe line, force the tool into the work another 1/64", reverse the lathe withoutremoving the tool, and feed...

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    Chapter 13Cutting off or Parting with a LatheYou can cut off in a lathe only when holding one end of the work rigidly, as in a chuck.It is not practical for long workpieces held between centers because the workpiece is notsupported closely with a rest and the free section is long enough to sag an...

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    Chapter 14Lathe Drilling and BoringYou can lathe drill on the MI-1220 LTD in two ways, holding the drill stationary andrevolving the workpiece, or holding the workpiece stationary and revolving the drill.Holding the drill stationary in a tailstock chuck gives a straighter hole (Figure 14.1). With...

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    Boring Boring is internal turning, or turning from within. The diameter of the opening to be boredis often much smaller than its depth. Boring tools must therefore have relatively smalldiameters and still support a cutting edge projected at considerable distance from thetoolpost or compound rest....

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    Figure 14.4 The cutting edge engages the work piece along a linein the mounted plane of the lathe centersFor straight longitudinal cuts, you can hold the cutter close up, therefore more rigidly, ifit's at a 90° angle to the bar. For machining ends of a bar, however, you need a boringbar that hol...

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    cutter approaches the workpiece. As with external thread cutting, the internal threadingtool must engage the work on dead center and be held so the cutter coincides with theworkpiece's center radius.In squaring the cutter with the work, use a center gauge (Figure 14.6) or thread gauge.Internal cu...

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    Figure 14.8 Use different clearances between nut and screw for different thread types.14: Lathe Drilling and Boring14-5Or Visit www.smithy.com

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    Chapter 15Changing Gears on Your MI-1220 LTDTo change gears on the MI-1220 LTD follow these steps. Tools required: 10-mm wrench 6-mm Allen wrench Screwdriver (to remove C clips) Pliers (to replace C clips) 1.Remove all C clips, nuts, and gears, starting with the A gear and ending with the Dgear. ...

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    Figure 15.2 Slide the B and C gear shaft until the C gear meshes with the D gear8.Place the selected A gear, flange side in, on the A gear shaft and replace the C clip. 9.Swing the bracket assembly until the A and B gears mesh. Hold the bracket assemblyin place and tighten the bolt. Make sure the...

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    Chapter 16 Cutting Threads on Your MI-1220 LTDThreading TermsBefore beginning to cut threads, it's useful to learn the major terms used in threadcutting: •Pitch.Metric pitch is the distance from the center of a thread to the center of the nextthread. To measure pitch in inches, measure an inch ...

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    After turning the work to be threaded to the outside diameter of the thread and settingthe gears for the desired thread, put a threading tool in the toolpost. Set it exactly on the dead center of the workpiece you'll be threading. To make sure your cutter is on dead center, place a credit card or...

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    Figure 16.3 Using a center gauge, set the threading tool perpendicular to the work piece.Cutting Right-hand Threads Place the leadscrew selector in position to feed the cutter from right to left, toward theheadstock. Now you are ready to cut right-hand threads. First, advance the tool so it justt...

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    Figure 16.5 When cutting multiple threads, increase the lead to make room for succeeding threads.Continue this process until the tool is within 0.010" of the finished depth. Brush thethreads regularly to remove chips. After the second cut, check the thread fit using a ringgauge, a standard n...

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    Table 16.1 Indicator ScaleCutting Multiple ThreadsCut multiple threads one at a time exactly as you cut single threads, except increase thelead to make room for succeeding threads (a double lead for a double thread, a triple leadfor a triple thread, etc.). After completing the first thread, remov...

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    Figure 16.7 When cutting a thread on a taper, set the threading tool at (missing text)Table 16.2 Threading Chart for the MI-1220 LTD30 15 70X4032 45 32 16 70 X 4032 48 0.50 1.00 49X4232 5628 14 70X4032 42 36* 18* 70 X 4032 54 0.60 1.20 49X4532 5026 13 70X4032 39 40* 20* 70 X 3...

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    Table 16.3 Feed Rates for the MI-1220 LTD27 X 2770 600.00110.00220.0010.000370 X 4032 450.01260.02520.00150.003070 X 4032 420.01350.02700.00160.003270 X 4032 390.01450.02900.00170.003470 X 4032 360.01570.03140.00180.003770 X 4032 330.01710.03430.00200.004170 X 4032 300.01890....

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    Chapter 17MillingIn milling, one or more rotating cutters shape a workpiece held by a vise or otherholding device. The cutters mount on arbors or at the end of the spindle in collets oradapters. Figure 17.1 MI-1220 LTD Milling/Drilling partsMachinists use mills to machine flat surfaces, both hori...

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    Push the mil head in the desired direction. Lock the main and centering locks to hold thehead into position To recenter the mill head, push the head into the approximate centered position. Movethe head back and fourth slightly while tightening the centering lock. The head will workits way into th...

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    Figure 17.3 Spring collets, which fit into the mill spindle, hold straight-shanked end mills.AdaptersAdapters mount various types and sizes of cutters on the spindle. Arbor adapters mountface mills on the spindle. Collet adapters mount end mills on the spindle. Taper-shank endmills mount in adapt...

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    5.Holding the adapter with one hand, use a non-marring hammer (rubber, dead-blow, orbrass) to drive the drift into the slot. The taper on the tool will release and the adapterdrop out. Cutters mounted in the spindle must fit accurately. There are two ways to make sure theydo. For small cutters, f...

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    •Geometry forming end millsform particular geometries. They include ball end mills,roughing end mills, dovetail end mills, T-slot cutters, key seat cutters, and shell end mills.•Ball end mills(Figure 17.6) cut slots or fillets with a radius bottom, round out pocketsand bottoms of holes, and d...

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    Plain Milling CuttersPlain milling cutters have teeth only on their periphery. Used to mill plain, flat surfaces,they may combine with other cutters to produce various shapes. They are cylindrical andcome in many widths and diameters. •Light-duty plain cuttersfor light cuts and fine feeds come ...

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    •Plain slitting sawsare thin, plain milling cutters with only peripheral teeth. The teethare fine, and the sides taper slightly toward the hole, giving side relief.•Slitting saws with side teethare like side milling cutters and are for deeper slotting andcut-off operations normally done with ...

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    Figure 17.9 Flycutters take light face cuts from large surface areas.Using Cutting FluidCutting fluids get rid of heat generated by the friction of the milling cutter against theworkpiece. They also lubricate the interface between the cutting edge and the workpieceand flush chips away. You can ap...

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    milling is the distance the cutting edge of a tooth travels in one minute. If cutting speedis too high, the cutter overheats and dulls. If it's too low, production is inefficient andrough. There is no exact right cutting speed for milling a particular material. Machinists usuallystart with an ave...

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    Down milling Down milling usually produces good surface finishes because chips do not sweep backinto the cut. Setups are more rigid, an advantage when cutting thin workpieces held in avise or workpieces held in a magnetic chuck. Down milling also produces straighter cuts.We recommend down milling...

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    Table 17.1 Recommended Cutting Speeds for Milling (fpm)MaterialBrinellHardness High-Speed-SteelCuttersCarbideCuttersFree-machining low carbon 1111steel resulphurized 1112100-150150-200120-160120-180400-600400-900Free-machining low carbon 10L18steel leaded12L14100-150150-220100-22511...

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    Common Milling Operations Milling Flat SurfacesOne way to mill a flat surface is by plane milling. Adjust the milling cutter vertically togive the needed depth of cut while the workpiece is held on the table and slowly feed ithorizontally. Every tooth on the periphery of the cutter removes a chip...

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    To cut bevels and chamfers, either move the workpiece into an angular cutter or hold theworkpiece at the desired angle while moving it into a plain cutter or end mill. You mayhold the workpiece in a vise or in a fixture held in a vise.Squaring a WorkpieceTo square the ends of a workpiece, use the...

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    Chapter 18WorkholdingThe most common ways to hold a workpiece during milling are to secure it directly to thetable via clamps or hold it in a vise (Figure 18.1). If you're making many similar work-pieces, you may make a special fixture to hold them. Whatever method you use, hold theworkpiece secu...

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    Using special fixtures. Clamp both workpiece and fixture securely in place. Be sure theyare clean. Watch them carefully during machining; a loose fixture or workpiece can bedisastrous. Dividing HeadsAlso called indexing heads, dividing heads attach to the table to hold workpieces betweencenters f...

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    Chapter 19TroubleshootingPowerfeed and Thread CuttingPowerfeed does not move carriageCauseSolution• Carriage locked• Unlock carriage• Speed selector not engaged• Select speed I or II• Leadscrew lever not engaged• Move lever to the left or right• Gears not meshing or teeth missing•...

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    Carriage/Milling TablePowerfeed doesn't move tableCauseSolution• Carriage• Unlock Carriage• Speed Selector not engaged• Select Speed I or 11• Leadscrew lever not engaged• Move lever to the left or right• Gear not meshing or teeth missing• Check and adjust gears• Crossfeed not en...

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    • Too much space between bearing and dial • Add shim washersLathe TurningCut is roughCauseSolution• Tool dull• Sharpen or replace tool• Tool not ground properly• Regrind tool• Tool at wrong angle• Correct tool position• Tools not held tightly• Tighten toolholder• Wrong cutte...

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    Too much backlash in compound CauseSolution• Loose spanner nuts• Tighten Spanner Nuts• Worn nut• Replace nutMachine slings oil from behind the chuck or in belt boxCauseSolution• Oil reservoir overfilled• Check oil level• Worn oil seal• Replacefelt in sealMillingTool chattersCauseS...

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    • Bit bent• Replace bit• Chuck loose in spindle• Remount chuck on arbor• Drawbar not secured• Tighten drawbar• Debris on spindle• Clean debris and arbor and remount tool• Bearings loose or worn• Tighten or replace bearings• Cutting too fast• Reduce speed• Incorrect bit...

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    Chapter 20Removing the Quill and Quill Feed AssemblyCautionHave the owner’s manual available when doing any machine maintenance. The itemsreferenced in these instructions can be found in the parts section of the owner’s manual. MAKE SURE THE MACHINE IS UNPLUGGED BEFORE STARTING ANY MAINTENANC...

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    Assembly1.Basic assembly is the reversal of the above steps.2.It is important to make sure all parts are clean and properly lubricated where needed.3.A thin coating of light grease should be applied to any sliding or rotating surfacesbefore assembly.*Note:If you should need to remove the spring, ...

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    Chapter 21MI-1220 LTD Full SpecificationsGeneral DimensionsLength53-1/2”Width20”Height37”Shipping Weight480 lbsMachine Weight397 lbsCrate Size57-1/2” x 22-3/4” x 38”Footprint54-1/2” x 32”T-Slot Size7/16”Accuracy+/- 0.001”Powerfeed (X-Axis)YesPowerfeed (Y-Axis)YesPowerfeed (Z-A...

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    Threads-Metric0.5 to 4 mmToolpost Travel3-1/4”Toolbit Size1/2”X-Axis Travel (w/tailstock installed)26”Y-Axis Travel8-1/2”Mill SpecificationsColumn Diameter3-1/8”Dial Calibration Drill-Coarse Feed0.042”Dial Calibration Mill-Fine Feed0.042”Drawbars Size (included)12 mm, 3/8”Drill Ch...

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    Chapter 23Machine Warranty30 Day Trial OfferTry a Smithy for 30 days. If, for any reason within that time, you decide to return yourSmithy, just call our Customer Service department at 1-800-476-4849. We will help youarrange shipping back to us. When we receive the machine back, we’ll refund yo...

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    In no event shall Smithy be liable for indirect, incidental or consequential damages for thesale or use of the product. This disclaimer applies to both during and after the term ofthis warranty.We do not warrant or represent that the merchandise complies with the provisions of anylaw or acts unle...

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