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    THE MICROMILL 2000 Desktop Machining System USER’S MANUAL MicroProto Systems December 2003

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    2 Table of Contents Introduction ……………………………………………………………………………… 3 Machine Setup ………………………………………………………………….………… 3 Installing the Axis Motors………………………………...

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    3 Introduction: Congratulations on your purchase of the MicroMill 2000 Desktop CNC machining system. We feel you have obtained the best value in the market today with a machine that will provide you with years of productivity and enjoyment. The MicroMill is a product of many years of Resea...

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    4 The axis stepper motors are coupled to each Lead Screw via 4 - 1/8” diameter nylon tubes. This coupling system was chosen for the following reasons: 1. To provide isolation of the motor bearings with any forces reflected from lead screw loads. 2. To provide a shock absorption coupling f...

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    5 Fig. 3b - Locking the Coupling Tube in place with the Clamp Ring. Assembling the Z-axis Column: The Z-axis column must next be aligned square with the table. In most cases this is a simple matter of using a standard machinist square set on the table and against the Headstock assembly as sho...

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    6 4. Move the indicator to the Left Side of the table and zero out the indicator. 5. Sweep the indicator to the Right Side and note the indicator deflection. 6. Carefully adjust the column until the indicator needle deflects to ½ of the previous reading. 7. Sweep the indicator back to the L...

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    7 MPS2003 version 3.0 Operation Manual Kurt E. Daley December 2003 Introduction: The MPS2003 program is a standard universal G-Code interpreter package that was designed with many full size CNC machining center features in mind. It supports most of the commonly used G and M codes t...

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    8 After booting into DOS change the drive to A by typing A: at the C:\WINDOWS prompt. At the A:\ command prompt type Install. This will then create the directory C:\MPSPRO on your computer and copy the MPS2003 program into it. Change back to the C drive and change the directory to this by typ...

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    9 This is where you input the filename of the program you wish to execute. The default file directory is C:\MPSPRO and can be changed with option 9. The filename can have any one to three letter appendage. Once entered this will be the current or active program to be executed. When Load Prog...

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    10 G01 Z0.5F5.0 G01 X1.0F10.0 G01 Y1.0 G01 X0.0 G01 Y0.0 This is a very useful function to use when you are cutting materials other than machinable wax such as Aluminum or Steel. In these cases a single cutting pass to the final cut depth is not possible and must be broken up into sever...

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    11 JOG INCREMENT … J Enters the JOG INCREMENT MODE that allows the user to specify a JOG INC distance to move the axes. Upon entering a value the axes are moved with the following keys. Pressing Enter with no value retains the previous value. Right Arrow = Move X-axis to the right for + ...

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    12 Allows the program to be repeated any specified number from 1 to 10000 times. The display shows the current loop number being executed along with the total number of times remaining. BACKLASH COMP … K Sets backlash compensation for each axis. The backlash is entered directly as a value i...

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    13 features that are below the material surface which is assumed to be set at Z = 0. All movements with Z greater then 0 are not displayed. The plot scale and X,Y offset values must be properly chosen, depending on the part being machined, in order to show the entire part in the Plot Window. ...

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    14 1.5-0.5-0.51.5(1,1) Fig. 7b - Shifted Plot Window Display with center at (1,1). The part reference position may not always be known and in this case you just run a PLOT PREVIEW and find where it is displayed at. You then guess at the center coordinates and enter them as the XYOFFSET value...

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    15 The MicroMill Fig. 8a - The MicroMill text engraving demo. Setup Procedure: 1. Execute the MPS2003 program by typing MPS2003 at the DOS prompt. 2. Select option # 1 MANUAL JOG. 3. Select F for Fast Jogging. 4. Select each axis and Jog the machine to a safe material loading posit...

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    16 4. Type P to enter the Plot Preview mode. This will then display PLOT PREVIEW on the screen. 5. Type option # 3 RUN PROGRAM. At this point the text will be drawn in the plot window as in figure 8a showing a preview of what the machined geometry will be. It is always a good idea to plot p...

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    17 Fig. 9 - Spindle set to top speed position. .NOTE: Once you become familiar with the machine and setting up the reference positions and so forth you may bypass the Preview and Dry Run steps and machine the part directly. The preceding process, though, is ALWAYS A GOOD IDEA when setting up...

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    18 Example Program # 3 (Drilling Holes): The next example shows the use of the MPS2003 program in drilling hole patterns using standard G83 peck drilling cycles. The following bolt hole pattern as displayed in figure 11 below will be generated. The program name is BOLTHOLE.TAP and contains 1...

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    19 Fig. 12 - Solid model representation of the finished 3D surface profile part FACEF.TAP. Machining Description: This example will consist of two machining operations being that of Roughing and Finishing. This requires a tool change and will, therefore, also demonstrate how to set a new to...

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    20 Roughing Operation: The first program file that will be executed is the Roughing Operation named FACER.TAP. The purpose of this roughing operation is to use a large diameter milling cutter to remove a large amount of material. This process leaves the part profile in a ‘Rough looking state...

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    21 tightened into the collet properly, a power line spike occurs or some other unexpected problem happens. CAUTION: Always wear your SAFETY GLASSES when inspecting a machining process up close. Chips can and will fly off randomly in all directions and will surely injure your eyes if they are u...

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    22 YX(1,1)(2,2) Fig. 15 - G01 X2.0Y2.0F10.0 movement from coordinate (1,1) to (2,2). G02 Clockwise circular interpolation at the specified feed rate F. Example (Absolute Positioning Only): G02 X2.0Y0.0I1.0J0.0F5.0 Start (0,0)End (2,0)I = 1J = 0Center(1,0) Fig. 16 - G02 Clockwise Circul...

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    23 Center(1,0)End (0,0)I = -1J = 0Start (2,0) Fig. 16 - G03 Counter Clockwise Circular Interpolation Move G17 Select the X,Y Plane for circular interpolation moves. G20 Select INCH mode programming. All values encountered will be interpreted as distances in inches and feed rates as inche...

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    24 G81X1.0Y1.0R0.1Z-0.25F5.0 The drill cycle moves to the (X,Y) location of the hole start point and then rapids to the R plane. It then proceeds at the feed rate F to the final drill depth. The process is completed by a rapid move back to the R plane or I plane. Material SurfaceR planeI p...

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    25 4. Feed down the incremental depth Q. 5. Rapid back to the R plane ( if G99 is activated ) or the I plane ( if G98 is activated ). 6. Rapid down to the point D (default value = 0.025 inch) above the last Q increment. 7. Feed down the next incremental depth of D+Q 8. Rapid back to the R o...

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    26 The G92 command can be very useful for repeating a part program at numerous locations. Suppose you are manufacturing small diamond inlays from wood and wish to cut out 4 per each piece of wood block you have. You have defined the bottom vertex as the reference position for the start of each...

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    27 X-0.375Y0.75 X0.0Y0.0 Z0.1 M99 G98 Return to I plane for drill cycles. G99 Return to R plane for drill cycles. M - Codes MO Program Stop. Upon reading an MO command the program stops and waits for the user to press C to continue program execution. M6 Tool Change. Upon reading an M6...

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    28 AXIS CONFIGURATION +X-X+Y-Y-Z+ZQuadrant1234+X-X+Y-YXY planeXYZ space Fig.20 - The Cartesian Coordinate System CNC MACHINE AXIS CONFIGURATION:

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    29 +X-X+Y-Y+Z-ZSpindleMachine table Fig.21 - Machine axis system for 3 axis Vertical CNC Machine (Machine axis defined by spindle movement) Rotary Table or 4th Axis Option: The 4th Axis Rotary Table is mounted on the left side of the X-axis table as shown in fig. 22 below. The rotary table axi...

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    30 Fig. 22 - Standard mounting position of the 4th Axis Rotary Table. TROUBLESHOOTING PROBLEMS PROBLEM: System does not work at all. CHECK: Fuse in back of unit (2A). PROBLEM: The motors don’t rotate at all when jogging. CHECK: If all the axis step motors don’t rotate and jus...

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    31 CHECK: The PORT BASE is probably configured to the wrong address. Change the port address by typing B and change the XYZ PORT BASE to either 632, 888 or 956. PROBLEM: The motors don’t step smoothly. There is an audible clicking that occurs when they are running. CHECK: Most likely ...

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    32 CHECK: This is normally no problem, but if it is going to sit idle for extended periods of time it is best to DESELECT the table or turn the unit off. PROBLEM: The step motors get very hot after prolonged use or idle time. CHECK: This is most evident when running the motors at high speed...

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    33 Fig. 23 - Checking Voltages inside the Electronic Driver Box. Shown are the range of voltages that will be present for a normally operating system. MACHINE MAINTENANCE 3A In-line Fuse Low Voltage Capacitor 8 to 9 Volts DC High Voltage Capacitor 51 to 55 Volts DC

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    34 Proper maintenance and care will assure that your MicroMill system will work at peak performance for many years of operation. Following the simple maintenance procedures below is all it takes to keep your machine in good running condition. Lubricating the Ways and Lead Screws: The steel ...

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    35 The backlash of each axis can be measured by mounting a Dial Indicator to a secure base with the contact point against the moving member as shown in figure A3 below. Fig. A3 - Measuring the X-axis Backlash. The following procedure will determine the backlash for the X-axis: 1. Enter the...

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    36 If your machine is running on a continuous basis and has accumulated many thousands of inches of travel on each axis throughout the years the Lead Screw Nuts may begin to show wear. This is evident if the backlash or play is larger then you think it should be. The backlash of a new system ...

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    37 This can be a Very Tedious process and can really throw the whole Lead Screw/Nut system out of calibration ( Much Too Tight or Too Loose) if not done in the proper fashion. If you are not very experienced with ‘The Feel’ a properly adjusted machine should have it is recommended that you ...

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    38 Fig. A5.2 - Brass Gib adjustment screws for the Saddle. Table Gib: The tapered brass gib on the table or X-axis is adjusted by the left side and right side Hex Screws shown in figure A5.3 below. Adjusting the left screw inward will tighten the table while adjusting the right screw inwa...

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    39 Adjusting the HeadStock: The Headstock is removed or re-positioned on the dovetail by loosening up the two Hex Screws shown in figure A6-A below. It is Very Important to NOT Over-Tighten these two screws when setting it back in place. Only a small tension is required to securely fasten the...

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    40 SuperCam Program For MicroMill users that have also selected the SuperCam program option the following information applies. SuperCam is a mini Cad/Cam program that allows the user greater flexibility in designing and machining parts. Please refer to the SuperCam Users Guide for a detailed...

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    41 IMPORTING BOBCAD FILES Standard BobCad G-code files can be used by the MPS2003 program. The files must be post-processed with the following procedure and options in BobCad. 1. Generate a BobCad part drawing. 2. Enter the NC-Cam window. 3. In Setup make sure the following parameters are ...

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    42 The Digitizing Probe program MPSPROB3.EXE must be run and is entered with option E from the main menu. It has the following options. PROBE PROGRAM: 1 = DIGITIZE 2 = SET PARAMETERS 3 = EXIT OPTION 1 Start the digitizing process OPTION 2 Set the digitizing probe parameters DIGITIZING...

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    43 Set the Z axis sample distance to 0.0005 inches. X TEST DISTANCE = 0.01 Sets the distance the X axis advances between contacts to 0.01 inches. For method 2 this is both the X and Y increment test distance. X STORE DISTANCE = 0.05 Records the X,Y, and Z coordinates with the X resolution of ...

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    44 4. Enter the Probe Program and select 1 to start the digitizing process. You are prompted to start the digitizing at this point. Hit ENTER to begin or the SPACEBAR to escape. NOTE: Once option 1 is selected the filename is rewritten. 5. The digitizing process can be HALTED at any time...

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    45 Fig. D - Methods of digitizing a surface.

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    46 LEADSCREW COMPENSATION The leadscrew on the MicroMill system, like any other machine system, may have slight variations from the true pitch of the screw. The standard screw pitch is 20 turns/inch for all three axes on the machine. For the 1.8 deg/step drive motors and half stepping mode...

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    47 SPEEDS AND FEEDS FOR DRILLING DRILLING SPEEDS (HIGH SPEED STEEL DRILLS): Material Average Drill Speed (sfm) Magnesium Alaaa 300 s Aluminum 250 Brass and Bronze 200 Copper as 70 Cast Iron (soft) 120 Cast Iron (hard) 80 Mild Steel 110 Cast Steel 50 Alloy Steels (hard) 60 Tool Steel 60 Stain...

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    48 SPEEDS AND FEEDS FOR MILLING MILLING SPEEDS (HIGH SPEED STEEL END MILLS): Material Average Tool Speed (sfm) Magnesium Alaaa 300 s Aluminum 250 Brass and Bronze 150 Copper as 100 Cast Iron (soft) 80 Cast Iron (hard) 50 Mild Steel 90 Cast Steel 80 Alloy Steels (hard) 40 Tool Steel 50 Stainl...

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    49 MILLING FEEDS: TOOL FEED (inch/tooth) Material Face Mills Side Mills End Mills Magnesium 0.005 - 0.020 0.004 - 0.010 0.005 - 0.010 Aluminum 0.005 - 0.020 0.004 - 0.010 0.005 - 0.010 Brass and Bronze 0.004 - 0.020 0.004 - 0.010 0.005 - 0.010 Copper 0.004 - 0.010 0.004 - 0.007 0.004 - 0....

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