The Business Master (4th Edition)

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[ D A N P L O T A N D D A N C A M ] DOCUMENTATION FILE CAMPLOT.DOC FOR DANPLOT.COM v2.5 AND DANCAM.COM v2.5 THE TWO COMPANION COMPUTER AIDED MANUFACTURING PROGRAMS FOR USE WITH DANCAD3D v2.5 Copyright (c) 1989-1991 by Daniel H. Hudgins, All rights reserved. Daniel H. Hudgins, 466 Diamond Street, San Francisco, CA 94114, USA SEE ALSO THE FILE DANCAD3D.DOC ON THE DANCAD3D SHAREWARE DISKS. USE THE PROGRAM PRINTDOC.EXE ON THE DANCAD3D SHAREWARE DISKS TO PRINT OUT THIS FILE IN ORDER TO HAVE THE PRINT CENTERED PROPERLY. You may not copy this DANCAM/DANPLOT disk, this documentation file or printed copies of this documentation file (other that to make a working copy for your own personal use) without obtaining express written permission form the author of this disk, i.e. Daniel H. Hudgins. Under no conditions is this DANCAM/DANPLOT disk to be sold for more than $10. None of the files of the DANCAM & DANPLOT disk may be altered, modified, deleted, or translated on copies of the DANCAM & DANPLOT disk that are to be sold, shared, or loaned without express written permission from Daniel Hudgins. The latest version of DANCAM and DANPLOT come with the disk set and manuals that are included with the DANCAD3D v2.5 user outfit. The DANCAD3D user order form is accessed from the opening menu that comes up when DANCAD3D v2.5 is run from DOS. Additional documentation and schematics for use with DANCAM and DANPLOT are supplied with the DANCAD3D user outfit. Please read all disclaimers and all warnings, notices, and danger statements before You use DANCAM or DANPLOT. Since DANCAM and DANPLOT control motors, and other electro-mechanical hardware, the use of DANCAM or DANPLOT can cause serious or fatal personal injury. It is assumed that the user of DANCAM and DANPLOT understands the dangers involved with working with power driven machinery, and high voltage circuitry, and will take any and all safety precautions necessary to protect himself and others from injury. Although DANCAM and DANPLOT are being used successfully, DANCAM and DANPLOT may not function properly at all times and are provided AS IS for you to USE ONLY AT YOUR OWN RISK. [1] [ D I S C L A I M E R A N D W A R N I N G ] DISCLAIMER Please remember that DANCAM can DANPLOT are sold AS IS, please use them ONLY AT YOUR OWN RISK. Daniel H. Hudgins will not be responsible or liable for any loss, damage, or injury of any kind. Please read the disclaimer that is in the DANCAD3D manual since it covers DANPLOT and DANCAM as well. Also read the disclaimer in the file DANCAD3D.DOC on the DANCAD3D shareware disks, as well as this disclaimer and the warning below. This documentation for DANCAM and DANPLOT may contain errors and or omissions. Under no circumstances or conditions will Daniel Hudgins be held accountable for any errors or omissions. This documentation includes suggested connections for hooking up devices to your computer's parallel port. Daniel Hudgins will not and shall not be held accountable or liable for any loss or damage that might occur to your computer to other devices. It is your responsibility to check and verify all the appropriateness of connections to your computer before turning on the power. Verifying the appropriateness of connections may require you to read and understand more information than this DANCAM and DANPLOT documentation contains. Under no circumstances are DANCAM or DANPLOT to be used in equipment that is used for medical purposes. DANCAM and DANPLOT should not be used in equipment that could cause injury to persons or loss of property if the equipment or software failed to operate properly. The use of DANCAM or DANPLOT is disallowed if any laws might require Daniel Hudgins to be in any way responsible or liable for any loss or injury. DANCAM and DANPLOT may not satisfy occupational safety laws in your state or country. No license to third parties is expressed or implied. No violation of copyrights or patents held by third parties is implied by the suggested use and connection of DANCAM and DANPLOT. The user should confirm that no copyrights or patents will be violated by his use of DANCAM or DANPLOT. The use of DANCAM or DANPLOT indicates full acceptance of all disclaimers and an understanding that DANCAM and DANPLOT are only to be used at the users OWN RISK. In this documentation the what is said about using stepper motors will also generally apply to servo motors and any other type of motors that might be used. It is a fact that any component can and should be expected to fail, therefore your safety depends on your not relaying of any particular component to protect you from harm. To improve your safety from harm use several stages of protection, so that if any single safety measure fails you have several others to back the failed [2] [ D I S C L A I M E R A N D W A R N I N G ] one up. Always be more careful than you think you need to be! WARNING Power driven and or automated equipment can cause serious injury or even death. You must take serious efforts to protect yourself and anyone else near such equipment. Do not place your hands or other body parts near power driven equipment without first disconnecting the power to the stepper motors (or other type of motors) in such a way that the motors and tool cannot harm you or others. DANPLOT and DANCAM are only to be used by people that understand the dangers involved and have been trained in the necessary safety precautions. Be aware that failure of electrical connections or computer hardware/software related faults can cause motors to start unexpectedly. To help avoid injury caused by unexpected motor starts you should disconnect the motor power at both the AC input of the motor power supply and the DC output of the motor power supply before you expose yourself or others to the equipment. Evaluation of the completeness of any safety measures is the users (your) responsibility. DO NOT USE any TSR program that puts a clock on the screen while the DANCAM or DANPLOT programs are in use! Do not use any multitasking, or print spooling programs while DANCAM or DANPLOT are in use! Such programs interfere with the computers CPU timing and therefore make the motors not run smoothly. Do not use the DOS screen dump command, e.g. [Shift] and [PrtSc], while running DANCAM or DANPLOT since the parallel port is not connected to a printer and the motors or auxiliary relays may be accidentally turned on (the computer may also lock up since the screen print command will not be getting the correct printer messages!) If the computer re-boots because of a power failure, your turning the computer off, your pressing [Ctrl] & [Alt] & [Del], or any other reason the voltage on the output pins of the parallel port may change and activate the auxiliary relays and other equipment in an inappropriate and possible harmful manner. You should investigate the default state of the parallel port pins after a computer reboot to determine if you have the high/low state for the output optimized to minimize any hazard. [3] [ A B S T R A C T ] ABSTRACT DANCAM and DANPLOT are two utility programs that you can use to automatically manufacture parts. DANCAM and DANPLOT run on your IBM (tm) compatible personal computer and use your personal computers parallel port to send motion control signals to almost any TTL signal compatible steeper motor translator/driver module, as well as using the parallel port to drive all the necessary control relays and to read all of the necessary home, limit and pause switches. If you have a desire to use servo motors in preference to stepper motors, a set of plans for a special closed loop servo motor driver compatible with DANCAM v2.52 and DANPLOT v2.52 is included in the DANCAD3D v2.5H user outfit, write to Daniel Hudgins for full information and pricing. Specifically DANCAM and DANPLOT are designed to read drawing files made with DANCAD3D.COM v2.5 and control stepper motors movement in such a way as to follow the lines drawn with DANCAD3D. You can attach stepper motors to almost any 2 or 3 axis machine tool or plotting type device's hand wheel (crank, knob) shafts to automate it. Additionally DANPLOT can be used to drive 4 axis devices where the forth axis (the "C" axis) keeps the cutting edge of a saber saw or knife blade pointed into the direction of the tool motion. DANCAM and DANPLOT offer very high possitional accuracy (when properly installed) and can be used for applications requiring fine accuracy to points spaced large distances (the actual accuracy of the cutting tool location depends on the quality of the device you are automating, e.g. flexing in the tool post and play in the ways will cause the tool to be slightly misplaced, if the error is repeatable you can adjust the tool path file with DANCAD3D to compensate for the errors.) Because DANCAM and DANPLOT are general purpose Computer Aided Manufacturing programs you can use them to automate most if not all of the types of machine tools you use. Additionally because of the extreme low cost and high repeatable accuracy of DANCAM and DANPLOT you may become interested in automating tasks that are currently done with manual hand labor. [4] [ O V E R V I E W O F D A N C A M A N D D A N P L O T ] ABOUT THE DANCAM AND DANPLOT DISK The DANCAM and DANPLOT disk has several example files on it in addition to the program files. Please read the file FILES.DOC for a description of the files on this disk. Before you can use the programs DANCAM or DANPLOT you will need to make a copy of this floppy disk and then delete the *.DOC files on your disk working copy. EXAMPLE: C>COPY A:*.* B: C>DELETE B:*.DOC The need to delete the *.DOC files is to make room for DANCAM and DANPLOT to save their configuration files i.e. DANCAM.CFG and DANPLOT.CFG. When you copy the configured versions of the programs remember to copy the *.CFG file along with the *.COM files. If you want to use DANCAM and DANPLOT from a harddisk just copy them into an appropriate subdirectory, i.e. if DANCAD3D v2.5 is on the harddisk just copy all the files into DANCAD3D subdirectory DC25. EXAMPLE: C>COPY A:*.* C:\DC25\*.* To print out this documentation file use the program PRINTDOC.EXE on the DANCAD3D shareware disks. If your printer is on the serial port use the DOS mode command to configure your serial port before trying to print the file. PRINTDOC.EXE will print the file centered on the page (the leading spaces have been omitted from this file to save disk space.) EXAMPLE: C>C:\DC25\PRINTDOC A:CAMPLOT.DOC PRN C>C:\DC25\PRINTDOC A:CAMPLOT.DOC LPT2 C>C:\DC25\PRINTDOC A:CAMPLOT.DOC COM1 OVERVIEW OF HOW DANCAM AND DANPLOT WORK DANPLOT and DANCAM are two programs that you can run on your computer to manufacture parts. YOU DO NOT NEED to understand or have any background in CNC or "G" codes to use DANCAM and DANPLOT. DANCAM and DANPLOT work in a SIMPLE AND DIRECT MANNER, they simply move the tool along lines and curves THAT YOU DRAW with DANCAD3D. All you have to do is draw on DANCAD3D's drawing screen a series of lines and curves in the order you want the tool to trace out those motions and DANCAM or DANPLOT will FOLLOW THE MOTIONS YOU HAVE DRAWN OUT. To use DANCAM and DANPLOT you simply go to a motor supply house and purchase some stepper motors and driver modules (instructions and schmatics for low cost stepper and servo motor driver modules and power supplies you can build are included in the DANCAD3D v2.5 user outfit.) You will also need a power supply (some driver modules are powered from the AC line and do not require a power supply) and a 36 pin mating connector for your parallel port cable. Connect the motors [5] [ O V E R V I E W O F D A N C A M A N D D A N P L O T ] to drive your machine's lead screws with timing belts and pulleys. Follow the connections shown in the drawing HOOKUP1.2D that comes on the DANCAD3D v2.5 shareware disks and connect up the motors, modules, and relays to the mating 36 pin connector (note that use of the information in this file and the HOOKUP drawings is at your own risk, Daniel Hudgins is not responsible for any damage or loss that might occur.) Connect the mating 36 pin connector to the printer end of your parallel port printer cable. Run DANCAM and/or DANPLOT and select menu option 4. from the DANCAM or DANPLOT main menu. Answer the questions in the configuration menu so that the motors will move the proper amount when the program is used. Press [E]scape to exit the configuration section. Try using main menu option 3. to manually move the motors. Use a dial gage if you have one to confirm that the tool is moving the proper amount (when you test the movement make the tool or work-piece move 0.25 inch two or three times in order to take up the backlash in your machine, and ignore the first reading.) Quit DANCAM or DANPLOT. Now that you have an automated machine tool or plotter hooked up to your computer you can use DANCAD3D v2.5 to make some ASCII type data files for tool paths. Run DANCAD3D and select DRAW from DANCAD3D's main menu. Draw the tool path. Save the tool path element as an ASCII type file (if you save the ASCII tool path to a floppy drive you can take the drawing from your home or office computer to the computer in the shop and read the drawing from the shop computer's floppy drive or copy the file to the shop computer's harddisk and read (execute) the drawing from the shop computer's harddisk (a single computer can be hooked up to many machine tools to have many parts made simultaneously, or each machine can have its own computer and the tool path file can be run separately and or concurrently on each machine tool.)) Quit DANCAD3D. Turn the power supply for the automation motors (DANCAM and DANPLOT can control relays to turn things on, but for safety reasons you should have a manual switch to control the master power supply.) Run DANCAM or DANPLOT, select menu option 1., and enter the name of the tool path, e.g. SOMEFILE.ASC or A:\SOMEFILE.ASC, to execute (execute means trace out the path drawn by moving the tool or work- piece relative to each other.) DANCAM or DANPLOT should then make your part for you. When the tool path is finished DANCAM or DANPLOT will return the tool to home position and be ready to make another part from the same tool path or another tool path file. You can file the floppy disk copy of the tool path so that if you ever need more parts, or replacement parts, all you have to do is shove the floppy disk in the computer and enter the tool path name to make another identical part. If you have manufacturing stations around the world you can send tool paths on floppy disks so that the remote stations can make up parts on demand locally and reduce your shipping and inventory costs. DOS batch files can be used to operate DANCAM and DANPLOT automatically to make several parts. The machine operator DOES NOT NEED TO USE ANY OF THE MENUS in DANCAD3D, DANCAM, and DANPLOT to [6] [ O V E R V I E W O F D A N C A M A N D D A N P L O T ] manufacture parts. The machine operator does need to understand the meaning of some of the messages that come on the screen (such as the DOS PAUSE command telling him to press ANY-KEY when ready) or at least know enough to alert a more knowledgeable operator when something goes wrong. The machine operator should also be told that the power driven tool can move unexpectedly and hurt him, therefore THE POWER TO THE MOTORS COILS SHOULD ALWAYS BE SWITCHED OFF BEFORE EXPOSING HIMSELF TO THE EQUIPMENT. Safety switches on the equipment access covers to turn off the motor coil power are advisable to help reduce injuries (to maintain possitional accuracy the logic power to the motor driver modules should not normally be switched off in the middle of a tool path execution, so when hooking up DANCAM and DANPLOT you should try to wire up two separate power switches: one for the motor coil power, and the other for the motor driver module logic power.) To summarize, using DANCAM and DANPLOT takes these steps: PHASE ONE: HOOKING IT UP 1. Hook up automation motors and switches mechanically to machine. 2. Hoop up electrical connections to modules and switches. 3. Configure DANCAM and DANPLOT to fit your mechanical hook up. 4. Test the installation to make sure the motors are working. PHASE TWO: COMPUTER AIDED DESIGN 1. Use DANCAD3D to draw tool paths for the tool paths needed. 2. Save the tool paths to floppy disks. 3. Write a DOS batch file to control the manufacture of the parts needed, and save the batch file to the floppy disk with the corresponding tool path files. Set up the AUTOEXEC.BAT on the shop computer so that the user will be prompted to insert the floppy disk with the tool path and batch file to control the number of parts to make. For safety, the batch file should prompt the operator to turn the motor power on and off at the appropriate points in the manufacturing cycle. PHASE THREE: MACHINE OPERATION 1. Turn power on to the shop computer. The AUTOEXEC.BAT file will automatically prompt the operator to insert the tool path disk. The AUTOEXEC.BAT file then runs the batch file on the tool path floppy disk (in order to have the AUTOEXEC.BAT file run the batch file of the floppy disk you would always use the same filename for the batch file on the floppy disk, e.g. GO.BAT.) 2. Operator inserts the stock and turns the motor power on. 3. Operators presses [Any-Key] to start making a part. 4. Operator is prompted to turn the power off, insert stock, and turn the power back on (it is important that a manual safety power switch be used since automatic control of power may not be reliable [7] [ O V E R V I E W O F D A N C A M A N D D A N P L O T ] (the manual control may not be reliable either, but the manual control of the power puts the responsibility for motor power on the user/operator).) 5. The manufacturing cycle continues under the direction of the batch files on the tool path floppy disks (i.e. GO.BAT can prompt the user to insert further floppy disks and run sub-batch files.) Phase three is of course not necessary if you are going to be the operator of the machine. In the case that you are doing all the work yourself you would save the data file on your harddisk from DANCAD3D and then run DANCAM or DANPLOT, turn on the power for the machine, and enter the filename of the tool path you saved to your harddisk. [8] [ P R O G R A M F E A T U R E S ] PROGRAM FEATURES DANCAM and DANPLOT both have several features that make setup and operation simple and relatively easy to accomplish: * All commands displayed on screen. * Menu driven configuration is adjustable to any units. * Works with tool paths drawn in metric, inch, or other units. * Motor testing utilities to check maximum motor speed under load. * Jog menu lets you position tool manually and has position read out. * Can be paused while making parts from keyboard or switch on port. * Supports up to four auxiliary relays to control anything. * Has automatic or manual home up to home switches. * Limit switches can be used to protect against out of range movement. * Can be operated from dos command line automatically. * Can be automatically operated from DOS batch files. * Uses user accessible DANCAD3D ASCII data file type. * Overall scaling factor to adjust part size. * Adjusts to any pitch lead screws or drive chain. * High accuracy over large distances of tool travel. * Works with any motor driver using step pulse and direction signals. * Feed rates can be installed from rapid movement to very slow. * Feed rate change, auxiliary relay toggle, and pause can be controlled automatically from line colors in the tool path file. * Installable delay after relay toggle lets equipment settle down. * Automatic backlash compensation when needed. * DANCAM is fully three dimensional and can make any three axis shape. * DANCAM and DANPLOT will run on almost any low cost PC compatible. * Low cost simple connection to parallel port, LPT1, LPT2, OR LPT3. When run on a 10 MHz 80286 computer DANCAM and DANPLOT can produce about 3420 step pulses per second which would run servo motors with 200 steps per revolution at a speed of about 1026 RPM. Most stepper motors have a reliable top speed less than 200 RPM so when stepper motors are used the reliable operation of the motors limits the top speed obtainable and not DANCAM or DANPLOT. The built in rate multiplier can be used to increase the step angle for servo drives (i.e. to 3.6 degrees) to get speeds of 2000 rpm or more since servo motors are normally feed through a 6:1 or 8:1 reduction before driving a 5 tpi lead screw, giving about 300 RPM at the lead screw or a feed of 60 inches per minute. [9] [ A P P L I C A T I O N S ] APPLICATIONS FOR DANCAM AND DANPLOT DANCAM and DANPLOT are similar programs, but each one has been optimized for different applications. DANCAM is designed for applications that require the tool or actuator to move between points at any location in three dimensions. DANPLOT is optimized for working on flat material, e.g. sheet or plate, and will automatically lift the tool or turn off the cutting flame or laser beam before moving to the next point in the drawing file. In other words DANCAM is used used for applications like 3D milling, and DANPLOT is used for plotter like work such as engraving and torch cutting. Both DANPLOT and DANCAM can draw circles and curves of any type. DANCAM can manufacture any part that can be produced on a three axis machine tool. The production of circles and curves takes place in DANCAD3D as part of the preparation of the drawing of the tool path. For complex contoured surfaces the tool path must define points that are more closely spaced than for the tool paths of parts than have flat surfaces. In the event that the tool path is to complex to fit entirely in DANCAD3D's workspace at once, the required tool path can be drawn in sections, and chained together for use with DANCAM or DANPLOT. DANCAM and DANPLOT can read tool path files of any length. DANCAD3D has special macro commands that can produce swept or contoured surfaces. The macro commands for DANCAD3D are explained in detail in the DANCAD3D manuals and example disks that come with the registered user outfit. APPLICATIONS DANCAM CAN BE USED FOR MAIN USES OF DANCAM * Three axis fully Three-Dimensional vertical milling. * Operation of lathes. * Cutting foam and other materials with hot wires. * Flame cutting where the torch height needs to be adjusted. * Laser cutting where the laser height needs to be adjusted. * Drilling holes to varying depths. ADDITIONAL POSSIBLE USES FOR DANCAM * Spray application where sprayer moves in three dimensions. * Glue application where applicator moves in three dimensions. * Welding, spot or arc. * Parts insertion, screw insertion, or nailing. * Automated warehouse loading and unloading. * Three axis motion control photography. * Automation of a motion picture animation stand. * Dipping of parts for coating by use of a gripper. * Processing film, PC boards, or micro chip wafers. [10] [ A P P L I C A T I O N S ] In addition to the linear three axis applications noted above DANCAM can be used to have one axis or more move in a non-linear manner. For instance the X axis could control a rotating table, so when the drawing for the motion of the X axis is drawn with DANCAD3D the person drawing the tool path would use units of arc (i.e. 0 to 360 degrees) rather than units of distance (e.g. 0.001 inch as +/- 10 inches.) For lathes the third axis in DANCAM can be used to control the spindle speed by connecting a small stepper motor to the shaft of an SCR speed control for the spindle motor. THREE AXIS APPLICATIONS WHERE DANPLOT CAN BE USED * Building a large pen plotter to plot drawings full life size. * Engraving scales and lettering. * Cutting fabric or leather from a pattern. * Drilling printed circuit boards. * Drilling holes to constant depth, slow down & fast up motion option. * Flame cutting with automatic flame control on the Z axis. * Laser cutting automatic laser on and off control on the Z axis. * Automated routing of wood for cabinets and stair runners. * Stamping or punching of sheet metal or other material. * Glue, Grease, Potting compound, OR Oil application. With DANPLOT the third (Z) axis can be used in several ways: you can control a stepper motor, you can control a relay, or you can control a solenoid. The normal use of the stepper motor for the Z axis would be to raise and lower the tool, such that the tool is not in contact with the work-piece when the tool moves to the next starting point if the line segments drawing in the file being executed to not touch. Additionally the Z axis stepper motor can be used to open or close a valve or rheostat. A relay on the Z axis direction control line can be used to turn a laser or other electrical device on or off. A solenoid triggered by the Z axis could be used to stamp or punch the sheet material. FOUR AXIS APPLICATIONS WHERE DANPLOT CAN BE USED * Knife cutting of signs out of vinyl. * Saw cutting of wood with a Saber, Band or Scroll saw. * Cutting fabric or leather from a pattern. * Broaching of key ways, groves, or gear teeth. * Automating nibbling tools. The forth or "C" axis (the c axis is rotation around the Z axis, such that the cutting edge of the tool is parallel to the Z axis) in DANPLOT will rotate the cutting edge of a knife or recriprecating saw so the cutting edge always faces into the direction of the motion the tool as the tool moves through the work-piece. A tolerance on how [11] [ A P P L I C A T I O N S ] large a C axis angle change is required before the tool will lift is available to speed the cutting of curves and circles (normally in knife cutting no harm comes if the knife rotates in the work-piece as circles are cut out, but you will want (and DANPLOT will perform) a tool removal, tool rotation, and tool insertion when large angle changes (such as at a 90 degree corner) need to be made. [12] [ G E N E R A L I N F O R M A T I O N ] GENERAL INFORMATION To use DANPLOT and DANCAM you will need to create a text file that contains information on the end points of line segments, such that the line segments define the path you want your tool (or work-piece as the motion between the tool and work-piece is relative) to move through space. The easiest way to create the necessary file of line segment data is to use DANCAD3D v2.5 to draw the line segments in the order you want them and in the direction you want the motion to proceed. The necessary line segment data file can also be made with a text editor or by a data file conversion program (to convert some other data filetype such as DXF, HPGL, or "G" code, into DANCAD3D v2.5 *.ASC file format.) Information about the DANCAD3D ASCII data file format is given in the DANCAD3D technical reference manual, but is not needed to use DANCAM and DANPLOT since DANCAD3D will create the proper file format for you automatically. DANPLOT and DANCAM are very similar programs but have each have special features to make them work better for their intended task. When you install DANCAM and DANPLOT by using the configuration utilities accessed from DANCAM's or DANPLOT's main menu you should keep in mind the different applications that the programs are designed for. DANPLOT is designed for use for working on flat or sheet material. The Z axis for DANPLOT has two states, up or on and down or off. DANPLOT can be used to build large plotters for plotting large drawings. A "C" axis motor can be used with its rotational axis parallel to the the Z axis in order to point the cutting tool into the direction of the motion of the cut (i.e. for use with knifes and saber saws.) The Z (pen) axis motor can be replaced with a relay to control (toggle) a laser or torch automatically (the Z axis direction pin on the port connector indicates the state, on or off.) Only the line segments that will appear on the work-piece need to be in the data file since DANPLOT will automatically lift the tool clear (turns off) of the work-piece when moving between the drawn line segments and when the tool path is done. Tool paths for use with DANPLOT have all points in the Z = 0 plane. DANCAM is designed for use for working on 3D parts where the tool moves in all three dimensions. The Z axis in DANCAM is equal to and interchangeable with to the X axis and Y axis. DANCAM is also useful for 2 axis work where the full motion of the tool will be drawn out. With DANCAM it is best to draw all motions out fully, including a safe path to the start of cutting, controlled feed rate for the cuts (the change in feed rate is accomplished by changing the line color in the tool path drawing), and a safe path from the final cut back to the home position (you can draw every other line segment in the tool path for DANCAM to reduce the total number of line segments in the data file, if you keep in mind that DANCAM will always take the shortest path through three dimensions to the next first point of the next line segment.) [13] [ G E N E R A L I N F O R M A T I O N ] When making a tool path files for use with DANCAM or DANPLOT keep the differences between the way the programs carry out the execution of line segments in the drawing file in mind. DANPLOT will read two types of file (ASCII and Plotter driver output) made with DANCAD3D. You can draw a tool path as a set of line segments or as a set of dots (holes to be drilled can be indicated by dots) with DANCAD3D without connecting the dots since DANPLOT will automatically lift the tool before moving to the next point (i.e. DANPLOT works like a pen plotter, such that the pen will automatically lift and move to the next line segment without drawing unwanted connecting line segments that were not in the DRAWING made with DANCAD3D.) DANPLOT can also read special plotter driver output files made in DANCAD3D with the DANPLOT.PLT plotter driver that accompanies DANPLOT on this disk. The plotter driver DANPLOT.PLT would be used for applications such as engraving that require DANCAD3D's line thickness attribute to be carried accurately to the finished result. For all applications other than engraving use DANCAD3D's ASCII filetype for tool paths that will be used with DANPLOT. DANCAM works like DANPLOT except the movement of the tool is fully 3D, with all 3 axis motors being simultaneously controlled by the lines you draw with DANCAD3D. DANCAM only reads the DANCAD3D v2.5 ASCII file format. DANCAM is useful for most 3 axis tasks such as vertical milling. You do however need to draw the tool path fully as a continuous series of line segments. If you skip a line segment DANCAM will take the shortest path to the next given point or to the home position currently installed in DANCAM's configuration menu if there is no next point to go to. So when you use DANCAM you should always draw all the movements you want the tool to make, including the safe path clear of the work-piece when done (in DANPLOT to tool automatically lifts to clear the work-piece when done and goes home, DANCAM can not automatically know what a safe return path is since dovetail mills or other odd shape cutters may be in use (DANCAM will take the shortest path from the last point drawn to home when done, so make sure the last point in the tool path is clear of the work-piece!).) HOW TO USE DANCAM AND DANPLOT In general the use of DANCAM and DANPLOT follows these steps: 1. Build or buy a machine to automate. Generally you will want the lead screws that have about 5 threads per inch so that the stepper motors 200 or 400 steps per shaft rotation will give a resolution of 0.001 or 0.0005 of an inch. Chain or timing cable drive in place of a lead screw is an excellent choice for drives that require less resolution and faster feed rates. Always try to minimize inertia in components that must be driven, i.e. use small [14] [ G E N E R A L I N F O R M A T I O N ] radius aluminum pulleys. 2. Install stepper motors on your machine. Use timing belts or flexible shaft (bellows) couplings between the motor shafts and lead screws to reduce noise and lost steps caused by vibration in the motor coupling. Stepper motors get hot (80C to 85C) in operation so proper mounting would allow the conduction of heat from the motor and circulation of cooling air. Used or surplus stepper motors can be purchased for a fraction of what new motors cost. In general stepper motors should have a rated holding torque that is at least FOUR TIMES THE TORQUE that will be required at the operating RPM (the torque of stepper motors falls off as the motor turns faster, so that a motor rated at 500 inch/ounce holding torque might only have 200 inch/ounce at 60 RPM, and only 100 inch/ounce at 120 RPM, with the torque falling completely to zero at 180 RPM.) Using stepper motors that are two small, and or running the motors faster than they can reliable go is the major cause of problems people have with stepper motors. Also stepper motors need to be operated at 4 to 6 times their rated voltage to give satisfactory results (a constant current stepper translator module or resistors in series with the motor windings are required to prevent the motor from overheating when operated at high voltages, i.e. 48 to 96 volts.) 3. Buy or build the stepper motor translator modules and motor power supplies (instructions for building the electronics required are included in the DANCAD3D v2.5 outfit's manuals.) Stepper motors generally operate with two coils (phases) on so the current draw is double the rated current, e.g. three motors rated at 2 Amps will require a power supply that can deliver at least 12 amps. The stepper driver translator modules you will need are available form your local motor distributor. Most stepper motor manufactures supply driver modules optimized for their own brand of motors. Surplus or used stepper motors can be purchased for a fraction of what new motors cost, e.g. 500 inch ounce motors can be found for less than $75. If you want to use solid state relays to control the spindle of your machine or other auxiliary device buy solid state relays that are rated for input of 3 volts DC or less since the parallel port cannot supply more than 3 volts (if more power is needed than the parallel port can supply a TTL buffer chip such as the 74H07 and pull-up resistors (approximately 330 ohm) can be used amplify the signal.) You can build your own stepper driver modules to drive three five amp motors for about $100 or less depending on how fancy you want to get. Ready made translator modules cost from $50 to $600 per axis depending on the power and speed required. 4. Use the diagram HOOKUP1.2D on the DANCAD3D v2.5 shareware or program disks to connect the stepper motor translator driver modules to your computers parallel port. If four auxiliary relays are to be used a 5 volt 500ma power supply (about a $10 item) will be required for the pull-up bias, otherwise the auxiliary C and D outputs can be used to pull-up the home and limit switch inputs (X, Y, and Z home switch inputs being pulled up through 10K ohm [15] [ G E N E R A L I N F O R M A T I O N ] resistors to auxiliary C output, and the pause/limit input being pulled up through a 5K ohm resister to the auxiliary D output pin.) 5. Run DANCAM and DANPLOT and install the values for speed and resolution that correspond to your machine. Test the motors under load to make sure they can keep up with the movements they will need to make. If the motors "louse steps" (that is slip and fail to rotate to the proper position) under load use a larger Pulse With Factor (p.w.f.) to give the motor time to complete one step before another is requested (if a stepper motor louses steppes the rotor will no longer have the proper rotational position (until the motors are sent home again which is a good reason for installing the home switches.)) Reducing the motor current to 80% of the rated current can sometimes reduce lost steps caused by resonance in the middle speed range. 6. Run DANCAD3D, draw a tool path, and save the tool path drawing as an ASCII data file (or a plotter driver output file if you need the line width feature for DANPLOT.) 7. Run DANCAM or DANPLOT, select menu option 1, and enter the file name of the ASCII (*.ASC) tool path file you just saved from DANCAD3D. If you did the installation properly your first part should come out as designed. If the first part is not proper adjust the installation and or the tool path drawing and try again. Keep in mind that DANCAM and DANPLOT can run from the DOS command line and therefore from DOS batch files. Operators of equipment do not need to use any of DANCAM or DANPLOT's menus since you can write a batch file to read the data file from a floppy disk automatically. [16] [ D O S C O M M A N D L I N E A N D B A T C H F I L E S ] EXAMPLE OF HOW TO RUN DANCAM OR DANPLOT FROM THE DOS COMMAND LINE To operate DANCAM or DANPLOT from the DOS command line simply enter DANCAM or DANPLOT followed by a space and then the name of the data file to be plotted and then followed by another space and the number 1 (or 1 or 2 for DANPLOT.) The number following the data filename is equilevent to the menu option number from DANCAM's or DANPLOT's main menu. EXAMPLE: C>DANCAM A:DATAFILE.ASC 1 C>DANPLOT A:DATAFILE.ASC 1 If you want to have one of the other menu options come up from the DOS command line you can use the dummy filename NUL. EXAMPLE: C>DANCAM NUL 3 C>DANPLOT NUL 3 EXAMPLE OF BATCH FILES THAT AUTOMATICALLY RUN DANCAM OR DANPLOT The following DOS batch file will make parts from data files saved on floppy disks. Note that all the data files should have the same name (when you save the DOS batch file you should always use the filename extension *.BAT.) EXAMPLE: :START ECHO OFF CLS ECHO PUT TOOL PATH DISK IN DRIVE A: PAUSE DANCAM A:DATAFILE.ASC 1 GOTO :START Since the floppy drives are somewhat slow you can get faster and smoother plots by coping the data file to a harddisk or RAM disk (the delay for the floppy drive to come up to speed when data is being read will cause the cutter to idle for a moment periodically, a problem that can be avoided by reading the data file from a harddisk or RAM disk.) EXAMPLE: :START ECHO OFF CLS ECHO PUT TOOL PATH DISK IN DRIVE A: PAUSE COPY A:DATAFILE.ASC C:\DC25\*.* DANCAM C:\DC25\DATAFILE.ASC 1 GOTO :START You can have DANCAM automatically run after you quit DANCAD3D by using a DOS batch file. To break a loop in a DOS batch file you need [17] [ D O S C O M M A N D L I N E A N D B A T C H F I L E S ] to press [Control] & [C] while the batch file is operating. EXAMPLE: :START CLS DANCAD3D DANCAM GOTO :START [18] [ H A R D W A R E R E Q U I R E M E N T S ] HARDWARE REQUIREMENTS Although DANCAD3D requires a fast computer and harddisk, DANPLOT and DANCAM can be used with a less expensive system. One advantage of using a less expensive computer in the shop with the automated equipment is that if the shop computer is damaged you will not have to spend much to repair it. In applications requiring higher motor shaft speeds (i.e. Greater than about 100 RPM) a 80286 replacement mother board can be put in an XT type case (replacement 80286 mother boards only cost about $140 or less.) Since a 10MHz 80286 XT size AT mother board can run as much as 8 times as fast as a 4.7MHz 8088 XT mother board it is very much worth the slight added cost to use a 80286 mother board for DANCAM or DANPLOT. DANCAM and DANPLOT will work on almost any IBM (tm) compatible PC that has one floppy drive and a IBM (tm) PC standard parallel port. No special hardware is required for the computer. Many standard stepper motor driver modules and solid state relays can be connected directly to the parallel port. The signals from the parallel port can be boosted with inexpensive parts to drive almost any other stepper driver module or relay that requires more power than the power the parallel port can supply. COMPUTER: 100% IBM PC-XT or AT compatible. PORTS: One Parallel Port is required, i.e. LPT1, LPT2, or LPT3. VIDEO: Any 80 column by 25 line video text display. MEMORY: 192KB RAM DOS system memory, 128KB or more free. DRIVES: 1 floppy disk drive. Reading the tool path data file from a RAM disk can avoid periodic short interruptions due to blocks of data being loaded from the data file. If you have 640KB on the computer you are using for DANCAM or DANPLOT a RAM disk program to make a 448KB RAM disk from your DOS system memory and have enough left over to run DANPLOT and DANCAM (you would copy the ASCII tool path data file into the RAM disk, and have DANPLOT of DANCAM read the tool path from the RAM disk drive.) A RAM disk is created by running a small utility program before you run DANCAM or DANPLOT. RAM disk utility programs are available from ShareWare dealers. CABLES: You will need a parallel port cable. If you have a printer connected to your computer you can use that cable. To connect the wires to the translator modules you will need a Centronics 36 pin connector that will mate with your printer cable. You can then solder wires onto the Centronics connector rather than your printer cable and that will allow you to disconnect the printer cable from the Centronics connector at any time to use the printer cable on your printer (reboot your computer after using DANCAM or DANPLOT [19] [ H A R D W A R E R E Q U I R E M E N T S ] before you use your printer.) If you buy a printer switch box make sure all of the needed pins are connected since some cheaper switch boxes may not connect all of the pins. The wire going between the parallel port pins and the input pins of the translator modules should be shielded. Microphone or video coaxial cable can be used with the shields of the two cables being tied to common (one cable for the step signal, and one cable for the direction signal.) Electro-Magnetic noise can be a problem because of a high current that flows through the wires that connect to the motor power supply and to the motors themselves. Always keep the step and direction cables as separated and far away from the motor coil wires as you can. Putting a 2.2K ohm pull up resistor from the step and direction inputs of the translator module to a positive five volt regulated supply can help reduce the input impedance of the translator module and therefore the voltage of induced electro-magnetic noise. Opto isolators, or LC or RC low pass filters on the inputs of translator modules can also help reduce incorrect triggering of the translator modules since opto isolators and filters reduce the input impedance. To filter the step and direction signals at the input of the translator module connect a 1000 pf capacitor from the input to common, connect a 2.2K ohm resistor from the input to +5 volts, and connect a 100 ohm resister between the input of the translator and the parallel port signal. If adequately shielded and filtered the parallel port to translator cable can be as long as 50 feet. Wire for connecting the motors should be stranded and large enough to handle the current required, i.e. 14 to 16 gage. The wires for the limit and home switches can be rather thin (22 gage) since very little current flows through the switches. MODULES: Stepper motor translator driver modules for stepper motors. Hundreds of different driver modules are available to drive different types of stepper motors. You will want TTL signal compatible modules that have MOTOR STEP (pulse) and motor DIRECTION (cw/ccw) inputs. Since steeper motors need to be operated at voltages above what the motors are rated for the stepper motor translator you purchase should offer some constant current or current cutback feature to keep the motors from burning up when they stop turning (stepper motors get hottest when run slowly or are stopped.) Two types of translator module that give good performance are Bipolar chopper and Bilevel Bipolar. Bipolar drives give more torque at medium speeds than Unipolar driver modules. You should check that the stepper motors you are going to use are compatible with the driver type you want to use. Regardless of the type of module selected the top motor speed will be less than the motor's best if the motor supply [20] [ H A R D W A R E R E Q U I R E M E N T S ] voltage is less than five times the rated motor voltage, e.g. a motor rated at 5 volts will run well with a 25 volt supply, but a 25 volt motor will need a supply voltage of 125 volts to run well. The maximum rated voltage of the motor driver module of course limits the supply voltage you can use. Modules also have a rated range of motor coil current they can handle (the coil current for the motors should never exceed the rated current!) RELAYS: Solid state relays such as the HAMLIN model 7521D or equivalent can be used to control auxiliary devices directly form the parallel port. The solid state relay should operate from a 3 volt or smaller signal. Solenoid relays can be controlled from the parallel port if you use a transistor and DC power supply (instructions for circuit details of such advanced wiring are in the DANCAD3D outfit's technical information.) POWER: External power supply. You will need a power supply powerful enough to drive all the stepper motors you are using. For medium duty tasks this would be 20 to 50 amps at 35 to 96 volts (stepper motors are run at voltages 4 to 6 times their rated voltage, so if you have motors rated at 10 volts you would want to have at least a 50 volt power supply (how high the power supply voltage can be is of course restricted by the maximum voltage of the translator modules you will be using.)) To determine the total current required figure that two coils will be drawing current in each stepper motor so if your motors are rated at 1 amp per coil and you have 3 motors you will need 6 amps plus another 4 to 6 amps for "headroom" due to the dynamic nature of the motor load. To assure that the motors can get all the current they need while stepping I recommend that you put a 20000 mf capacitor across the power supply input of each of your motor driver modules. A 5 volt 500 ma power supply may also be required to bias any pull-up resistors required. SWITCHES: Three Normally Open (N.O.) micro switches for home switches. Six Normally Closed (N.C.) micro switches for limit switches. One Normally Closed (N.C.) toggle switch for pause switch. One Normally Open (N.O.) push button for bypass button. RESISTOR: Five 2.2K ohm 1/4 watt, for pull-up of the switch inputs (pull-up resistors connect from TTL logic IC's inputs or outputs to a plus five volt power supply (the common from the five volt power supply would of course connect to the logic common or ground.)) Since the switches connect between the input pins of the parallel port and common the pull-up resistors are needed to insure that the input pins are always at logic high (logic high is 2.8 to 5.0 volts.) If you do not want to use a special 5 volt supply for the limit and home switch inputs you can use 10K ohm 1/4 watt [21] [ H A R D W A R E R E Q U I R E M E N T S ] resistors from the input pins to auxiliary outputs C and D (of course auxiliary C and D cannot then be used for relays since they will need to be logic high all the time.) HARDWARE: To mount the motors you will need flexible shaft couplings (metal bellows type) or timing belts and pulleys. It is important that the coupling used on the stepper motor have about 0.5 degree of give (elasticity) so that the motor can step easily and smoothly and without excessive vibration. [22] [ H O O K U P C O N E C T I O N S ] HOOK UP CONNECTIONS TO THE PARALLEL PORT The complete schmatic for the basic DANCAM and DANPLOT hook up is provided in drawing file HOOKUP1.2D on the DANCAD3D v2.5 shareware program disks. Printing out the HOOKUP1 drawing will make reading this section much more understandable. Additional schmatic diagrams are included in the DANCAD3D outfit. This following information gives all the basic connections for using DANCAM and DANPLOT. DANPLOT and DANCAM use the same basic connections to the pins of the parallel port. The basic connections to the 36 pin printer end of the Centronics parallel port cable are: Pin No. 36 18 35 17 34 16 TIE TO COMMON - 33 15 AUXILIARY INPUT - 32 14 AUXILIARY RELAY "D" OUTPUT - 31 13 - Z AXIS HOME SWITCH INPUT TIE TO COMMON - 30 12 - Y AXIS HOME SWITCH INPUT TIE TO COMMON - 29 11 - X AXIS HOME SWITCH INPUT TIE TO COMMON - 28 10 - LIMIT & PAUSE SWITCH INPUT TIE TO COMMON - 27 09 - AUXILIARY RELAY "B" OUTPUT TIE TO COMMON - 26 08 - Z AXIS DIRECTION OUTPUT TIE TO COMMON - 25 07 - Y AXIS DIRECTION OUTPUT TIE TO COMMON - 24 06 - X AXIS DIRECTION OUTPUT TIE TO COMMON - 23 05 - AUXILIARY RELAY "A" OUTPUT TIE TO COMMON - 22 04 - Z AXIS STEP PULSE OUTPUT TIE TO COMMON - 21 03 - Y AXIS STEP PULSE OUTPUT TIE TO COMMON - 20 02 - X AXIS STEP PULSE OUTPUT TIE TO COMMON - 19 01 - AUXILIARY RELAY "C" OUTPUT All of the input pins must be "pulled up" to logic high through 2.2K ohm 1/4 watt resistors to a +5 volt regulated power supply (you should be able to find a +5 volt 500 milliampere power supply for less than $10 (you can use three flashlight 1.5v dry cells in series to get about 4.5 volts, but NEVER use more than 5 volts or less than 3 volts.)) ALWAYS check that the MINUS (-) end of the five volt supply connects to the COMMON point, since reversed connections will damage your parallel port and possibly other parts of your computer. If you do not want to bother with a +5 volt power supply and do not need to use the auxiliary outputs "C" and "D", you can usually use the auxiliary outputs "C" and "D" to pull up the switch inputs, as shown here: [23] [ H O O K U P C O N E C T I O N S ] Pin No. 36 18 35 17 34 16 TIE TO COMMON - 33 15 AUXILIARY INPUT - 32 14 PULL UP FOR PIN 10 & 32 - 31 13 - Z AXIS HOME SWITCH INPUT TIE TO COMMON - 30 12 - Y AXIS HOME SWITCH INPUT TIE TO COMMON - 29 11 - X AXIS HOME SWITCH INPUT TIE TO COMMON - 28 10 - LIMIT & PAUSE SWITCH INPUT TIE TO COMMON - 27 09 - AUXILIARY RELAY "B" OUTPUT TIE TO COMMON - 26 08 - Z AXIS DIRECTION OUTPUT TIE TO COMMON - 25 07 - Y AXIS DIRECTION OUTPUT TIE TO COMMON - 24 06 - X AXIS DIRECTION OUTPUT TIE TO COMMON - 23 05 - AUXILIARY RELAY "A" OUTPUT TIE TO COMMON - 22 04 - Z AXIS STEP PULSE OUTPUT TIE TO COMMON - 21 03 - Y AXIS STEP PULSE OUTPUT TIE TO COMMON - 20 02 - X AXIS STEP PULSE OUTPUT TIE TO COMMON - 19 01 - PULL UP FOR PINS: 11, 12, & 13 The value of the pull up resistor will need to be increased to 10K ohm when auxiliary "C" and "D" are used as the pull up source to avoid over loading the parallel port. When the auxiliary input on pin 32 is not used a 4.7K ohm resistor can be connected between pin 31 and pin 10 in place of a 10K ohm resistor. The home switches are normally open (N.O.) and connect between the home switch input pins and the common (ground) point. The six limit switches, and pause switch, are normally closed (N.C.) and are connected in series between pin 10 and the common point. The bypass push button for the limit switches is normally open (N.O.) and connects from pin 10 to the common point. If one of the limit switches opens (due to out-of-range travel, the motors will stop, and an error message will come up on the computer screen) press the [Control] and [X] keys on the keyboard and then press the limit switch bypass button you wired from pin 10 to the common point. When installing the limit switches at the home end of the travel be sure that the limit switches become open several motor steps AFTER the home switches have closed (otherwise the motors will stop before the home position is reached!) The WINDOW command in DANCAD3D should be used to clip the tool path before you save the tool path to an ASCII file to avoid out-of-range motions. DANPLOT can be hooked up in some additional configurations. In order to use the C axis the auxiliary relay "A" and "B" output pins are used for the C axis step and direction signals, and the auxiliary input is used for the C axis home switch: [24] [ H O O K U P C O N E C T I O N S ] Pin No. 36 18 35 17 34 16 TIE TO COMMON - 33 15 C AXIS HOME SWITCH INPUT - 32 14 AUXILIARY RELAY "D" OUTPUT - 31 13 - Z AXIS HOME SWITCH INPUT TIE TO COMMON - 30 12 - Y AXIS HOME SWITCH INPUT TIE TO COMMON - 29 11 - X AXIS HOME SWITCH INPUT TIE TO COMMON - 28 10 - LIMIT & PAUSE SWITCH INPUT TIE TO COMMON - 27 09 - C AXIS DIRECTION OUTPUT TIE TO COMMON - 26 08 - Z AXIS DIRECTION OUTPUT TIE TO COMMON - 25 07 - Y AXIS DIRECTION OUTPUT TIE TO COMMON - 24 06 - X AXIS DIRECTION OUTPUT TIE TO COMMON - 23 05 - C AXIS STEP PULSE OUTPUT TIE TO COMMON - 22 04 - Z AXIS STEP PULSE OUTPUT TIE TO COMMON - 21 03 - Y AXIS STEP PULSE OUTPUT TIE TO COMMON - 20 02 - X AXIS STEP PULSE OUTPUT TIE TO COMMON - 19 01 - AUXILIARY RELAY "C" OUTPUT You still have auxiliary outputs "C" and "D" available if you need to have control relays and use a +5 volt supply for the pull up resistors on the switch inputs. So the C axis above hook up can connect to four motors and two relays. Another option when hooking up DANPLOT is to use the Z axis direction bit to control a relay or solenoid rather than a stepper motor. This option gives you the possibility of two motors and five relays: Pin No. 36 18 35 17 34 16 TIE TO COMMON - 33 15 AUXILIARY INPUT - 32 14 AUXILIARY RELAY "D" OUTPUT - 31 13 - Z AXIS HOME SWITCH INPUT TIE TO COMMON - 30 12 - Y AXIS HOME SWITCH INPUT TIE TO COMMON - 29 11 - X AXIS HOME SWITCH INPUT TIE TO COMMON - 28 10 - LIMIT & PAUSE SWITCH INPUT TIE TO COMMON - 27 09 - AUXILIARY RELAY "B" OUTPUT TIE TO COMMON - 26 08 - Z AXIS RELAY OUTPUT TIE TO COMMON - 25 07 - Y AXIS DIRECTION OUTPUT TIE TO COMMON - 24 06 - X AXIS DIRECTION OUTPUT TIE TO COMMON - 23 05 - AUXILIARY RELAY "A" OUTPUT TIE TO COMMON - 22 04 TIE TO COMMON - 21 03 - Y AXIS STEP PULSE OUTPUT TIE TO COMMON - 20 02 - X AXIS STEP PULSE OUTPUT TIE TO COMMON - 19 01 - AUXILIARY RELAY "C" OUTPUT [25] [ H O O K U P C O N E C T I O N S ] When using a relay on the Z axis you need to set the default state for the Z axis direction bit and the rotation of the Z axis motion so that the relay is off before the tool path starts and is automatically set off when the tool path ends, by using the configuration setup menu option number 4. from the DANPLOT and DANCAM main menus. Normally this means default to logic low and have the Z axis motion -10 to -200 steps. The pulse width factor for the Z axis can be used to control the delay after the Z direction bit changes before the X and Y motors start to turn (to allow for the time the Z axis relay/device takes to respond.) You can of course use the C axis motor and a Z axis relay if you want to (three relays and three motors.) You can omit the home and limit switches if you wish, since both DANCAM and DANPLOT can operate without the switches connected. The minimum hook up would be: Pin No. 36 18 35 17 34 16 TIE TO COMMON - 33 15 32 14 31 13 TIE TO COMMON - 30 12 TIE TO COMMON - 29 11 TIE TO COMMON - 28 10 - TIE TO COMMON TIE TO COMMON - 27 09 TIE TO COMMON - 26 08 - Z AXIS DIRECTION OUTPUT TIE TO COMMON - 25 07 - Y AXIS DIRECTION OUTPUT TIE TO COMMON - 24 06 - X AXIS DIRECTION OUTPUT TIE TO COMMON - 23 05 TIE TO COMMON - 22 04 - Z AXIS STEP PULSE OUTPUT TIE TO COMMON - 21 03 - Y AXIS STEP PULSE OUTPUT TIE TO COMMON - 20 02 - X AXIS STEP PULSE OUTPUT TIE TO COMMON - 19 01 If you wish to connect directly to the pins on your parallel port card 25 pin connector rather than use the printer end of a parallel port cable the connections are: [26] [ H O O K U P C O N E C T I O N S ] Pin No. 13 - Z AXIS HOME SWITCH INPUT TIE TO COMMON - 25 12 - Y AXIS HOME SWITCH INPUT TIE TO COMMON - 24 11 - X AXIS HOME SWITCH INPUT TIE TO COMMON - 23 10 - LIMIT & PAUSE SWITCH INPUT TIE TO COMMON - 22 09 - AUXILIARY RELAY "B" OUTPUT TIE TO COMMON - 21 08 - Z AXIS DIRECTION OUTPUT TIE TO COMMON - 20 07 - Y AXIS DIRECTION OUTPUT TIE TO COMMON - 19 06 - X AXIS DIRECTION OUTPUT TIE TO COMMON - 18 05 - AUXILIARY RELAY "A" OUTPUT TIE TO COMMON - 17 04 - Z AXIS STEP PULSE OUTPUT AUXILIARY RELAY "D" OUTPUT - 16 03 - Y AXIS STEP PULSE OUTPUT AUXILIARY INPUT - 15 02 - X AXIS STEP PULSE OUTPUT 14 01 - AUXILIARY RELAY "C" OUTPUT You can of course adjust connections on the 25 pin connector to correspond to any of the alternate hook-ups, e.g. use auxiliary input on pin 15 for the C axis home switch, and or use the auxiliary relay "D" output on pin 16 to pull up pin 10. As you have probably noticed pins 1 through 13 have the same connections on both the parallel port 25 pin connector and the 36 pin parallel printer cable connector. [27] [ C O N F I G U R E A N D I N S T A L L ] CONFIGURE AND INSTALL DANCAM and DANPLOT send messages to the motor translator modules in the form of what are called "steps". The motor shaft rotation is divided into fractions, usually 1.8 degrees per step, or 200 steps per 360 degrees (360/200=1.8). Sometimes motors are run "half step" mode where the step is divided in half, e.g. 400 per revolution of the motor shaft. Micro stepping divides the motor step into smaller parts, but does not usually offer higher actual possitional accuracy under fluctuating loads since the motor shaft of a stepper motor will typically exhibit 0.9 degrees of possitional error when driven under full load from clockwise, and then counter-clockwise rotation. For servo motors the shaft encoder defines the minimum rotational interval or "step." Note that the unit name inches is given in the configuration menus in DANCAM and DANPLOT even though any units can be used so long as all of the set up is done in the same units of measurement. This was done to avoid the confusion some users have about the meaning of the word units. You will also have to set the overall scaling factor in the configuration menu of DANCAM and DANPLOT to relate to the units scaling factor used while drawing the tool path in DANCAD3D. If this gets confusing, just set the global scale in DANCAD3D at 240 and configure DANCAM and DANPLOT in steps per inch, and set the DANCAM - DANPLOT overall scaling factor to 1 (then one unit in DANCAD3D's drawing editor will move the tool one inch (this is the default configuration.)) So since the motor shaft has finite positions that it can stop at, the driven load will also have finite positions it can stop at. When working out the ratio of the timing belt pulleys for the motor and lead screw you should figure that one motor step should move the work- piece relative to the tool by one half the smallest amount necessary. If you are machining to 0.001 of an inch and have a 10 pitch lead screw then 1:1 coupling of the stepper motor will give you 0.0005 inches of movement per motor step, i.e.: 200 steps per revolution -------------------------- = 2000 steps/inch = 0.0005 inches/step 0.1 inch per revolution Successfully installing DANCAM or DANPLOT requires having the motors installed to give the coarsest resolution that will be acceptable. Excessively fine resolution will limit the maximum speed the tool can move (because the steps per second is constant.) Reducing the resolution will increase the maximum speed the tool can travel. In our example we can calculate the maximum tool feed speed in inches per minute from the motor RPM, since with 1:1 drive the tool will move 0.1 inch per revolution, and 120 RPM would be a reliable maximum speed for the motor shaft. [28] [ C O N F I G U R E A N D I N S T A L L ] 120 revolutions per minute -------------------------- = 12 inches per minute 10 revolutions per inch Feed rates for other resolutions can be worked out for the motor shaft speed of 120 RPM and 1:1 shaft coupling: LEAD SCREW FEED/REV STEPS/INCH INCH/STEP INCHES/MINUTE 2.5 tpi 0.4" 500 .002 48 5.0 tpi 0.2" 1000 .001 24 10.0 tpi 0.1" 2000 .0005 12 20.0 tpi 0.05" 4000 .00025 6 Since the torque of stepper motors falls off the faster the motor turns you may only be able to get reliable operation at speeds slower than 60 RPM. In general doubling the voltage used to drive a stepper motor will increase the top speed by 50%, i.e. if a motor works well at 60 RPM at 24 volts you can probably get it up to 90 RPM by increasing the voltage to 48 volts. The top voltage for stepper motors is about five times the rated voltage, you will of course need to limit the current to the rated current to avoid burning out the motor (in the simplest scheme a series power resistor is used to limit the current flowing through the motor winding when the motor is not turning to the rated current, because the motor is an inductive load the resistor will allow the voltage to rise briefly at the beginning of each motor step before the voltage drops back to the static level, thereby making the motor turn faster.) When building a plotter you can drive the pen holder by using a timing belt driven directly by a pulley. Small motors can generally run at 240 RPM in half step mode to give 1600 (half) steps per second. PULLEY DIAMETER FEED/REV STEPS/INCH INCH/STEP INCHES/SECOND 0.25" 0.785" 509.55 0.00196" 3.14159" 0.50" 1.570" 254.65 0.00392" 6.28318" 0.75" 2.356" 169.76 0.00589" 9.42477" 0.10" 3.141" 127.32 0.00785" 12.56636" When selecting stepper motors to drive your equipment you should use motors that have a rated holding torque AT LEAST FOUR TIMES the torque that will be required under load and at full speed. Also use the motor testing utilities built into DANCAM and DANPLOT to do the start and stop test to make sure that the spacing of the pulses sent to the motor translator module are far enough apart (a larger pulse [29] [ C O N F I G U R E A N D I N S T A L L ] width factor will space the pulses wider apart) for the motor to keep up with the step pulses (if the pulses are to fast the motor will not come back to the point it was at at the beginning of the motor test, indicating unreliable operation.) The ramping should be set to 0 when testing stepper motors. I would like to warn you that stepper motor manufactures published speed v.s. torque curves can be very optimistic, and are not generally applicable to use with DANCAM or DANPLOT. As a rule of thumb based of my experience you can expect these values for maximum top speeds for reliable error free operation under working load, with the higher RPM number being obtained by using the maximum voltage the motors can take (when the voltage is more than six times the rated voltage stepper motors may become unstable in the middle of the motors speed range, so you are limited in how much the motors can be boosted): MOTOR HOLDING TORQUE MAXIMUM MOTOR SHAFT SPEED 20 - 40 in/oz 240 - 300 RPM 40 - 150 in/oz 120 - 240 RPM 150 - 400 in/oz 90 - 120 RPM 400 - 1500 in/oz 30 - 90 RPM To configure DANPLOT and DANCAM to produce the proper number of steps per inch of travel simply run DANCAM or DANPLOT from DOS and select mode #4 from the main menu that comes up. Since stepper motors typically can only step 300 to 1000 full steps per second (600 to 2000 half steps) the motor step delay of 0.5 ms to 3 ms is needed to keep the motors working properly. The minimum motor single step delay is controlled a value called the pulse width factor (p.w.f.). Each axis has its own p.w.f so the motors can run as fast as possible (allowable) when the maximum feed rate is requested. When you install DANCAM and DANPLOT using their main menu option #4, be sure to work through the sub-menu options in order 1,2, (sub- menu of 2 options 1,2,3 for each axis) and then 3,4, and 5. When you work through the menus keep in mind the number of steps the motor shaft makes per revolution. If you run a motor in half step mode then multiply the number of motor steps by two. For servo motors the number of steps per revolution can be derived from the encoder counts per revolution and any pulse rate multiplier used. In the motor test sub-menu (#2 in the configuration menu) use option #1 to find the smallest p.w.f. that makes the motor run smoothly under load, use #2 (of #2 of #4) to check that the motor is not missing any steps (make the p.w.f. larger if the motor is missing steps and test again), and use #3 (of #2 of #4) to test the RPM if needed. When the p.w.f. has been configured for each axis press [Esc] to go back to the installation sub-menu and answer the other questions. The ramping should be set to 0 for testing stepper motors. [30] [ C O N F I G U R E A N D I N S T A L L ] The questions in option #3 in the installation sub-menu should be used to install the scaling factors before you enter the feed rate controlling delays with option #4. In this version of DANPLOT and DANCAM the feed rate is controlled by a delay between motor steps. Since the p.w.f. keeps each motor working properly the feed rate delay can vary from 0 to 65000000 micro seconds per step depending on how slow you want the feed. To get different feeds, enter the delays you want in the feed rate table, then make the tool path drawing with DANCAD3D so that the line segments have the color attribute that corresponds to the delay set in the feed table. The line color attribute is set while drawing in DANCAD3D v2.5 by pressing the [L] key of the keyboard or by using the mouse to click on the with [L]ine style option of the [L]ines sub-menu from the drawing editor root menu. Any step delay value can be assigned to any line color number. Set all the delays to 0 if you want the tool to move as fast as possible for all motion. Another configuration menu option lets you assign which line colors will turn on or off the auxiliary control relays. Line segments used to control the auxiliary relays can have starting and ending points at the same location (i.e. zero length.) Option #5 of the installation sub-menu asks about the home switches. Both DANPLOT and DANCAM let you install home switches on your equipment so that you can have the tool automatically home up before each tool path file is read. The ability to home up automatically can be a great time saver. You should note that without the use of the switches to home up, an error of +/- 3 full motor steps can occur when DANPLOT and DANCAM are first run since the motor rotors will jump to the position dictated by the mechanical relationship of the motor rotor and the state of the motor winding sequence that the motor controller starts with. Most stepper motor controllers start with the same coil (phase) energizition pattern, so you can loosen the motor coupling, reboot your computer, re-run DANPLOT or DANCAM and tighten the motor coupling with the tool carrier at it's home position. Lousing, rebooting the computer, and tightening the motor coupling will not help if the motor controller initializes with a random energizition of the motor windings, in such a case you would have to use the home switches or manually check to see if the motors shafts have an incorrect position and use main menu option #3 to get the motor shafts into the proper starting orientation. DANPLOT has some additional special configurations. The "C" axis lets you mount a fourth motor with its shaft parallel to and centered on the Z axis such that a knife, saw, or broach will automatically rotate to point the cutting edge into the motion of travel. The tolerance on the C axis lets the tool stay down while cutting out curves. The manual up and down option lets you manually activate the Z axis for use in automating a drill press with two motors (one for X axis and one for Y axis.) In manual up/down mode the work-piece is positioned and then the computer is made to pause while you drill the hole, then you press a key on the keyboard and the work-piece will [31] [ C O N F I G U R E A N D I N S T A L L ] move to the next position, and so on. [32] [ D R A W I N G T O O L P A T H F I L E S ] DRAWING TOOL PATHS WITH CUTTER TOOL COMPENSATION The following are the steps required to draw a tool path element while being able to visually see the shape of the cutter on the computer screen. Please read the file DANCAD3D.DOC on the DANCAD3D v2.5 program disks and read the menus in the DANCAD3D program drawing editor to learn more about what these steps mean. NOTE: You will need DANCAD3D v2.5H or later to draw cutter paths with compensation for the cutter shape. 1. Run the DANCAD3D program. Press [Return] until you reach its main menu. 2. Select [D]raw from the DANCAD3D main menu. Select the [F]ront view. If the drawing workspace is not empty select [I]nitialize to clear the workspace. 3. Select [D]raw from the drawing editor root menu. Draw an outline of the shape of the finished work-piece you wish to make. You can make the inside corners sharp if the radius will be determined by the cutter shape. You can make the shape outline in 3D if you are going to do 3D work. Remember that lathes are 2 axis devices, so the tool path for the lathe will be 2D (i.e. a profile.) You can include an outline of the raw material in the outline of the finished piece to make visualization of the amount of material to remove easier. The outline of the work-piece can include outlines of holding fixtures and other machine parts so that you can check for interference with the cutter. 4. The next step is to make an outline for the cutting tool. If you are going to use an end mill you can use the [P]olygon command (try to keep the sides total to 36 or less) in the 2D shapes drawing editor sub-menu. For other shape cutters press [B] to begin a new element (element 2) and draw the outline of the cutter. The center of the cutter outline element should be on the cutter's axis of rotation if the cutter rotates. The cutter outline can be 3D and include the tool holder or tool post so that you can visually check for interference with the work-piece or other parts of the machine. 5. To draw the actual tool path element go into the drawing editor's [E]lements sub-menu and select [D]rag. Select [E]nter element number and enter the element number for the cutter outline (element 2.) Select the element center as the reference point. Press [Return] to start the drag command. The cutter outline will blink. Press [B]egin element to begin the tool path element (the tool path will be element number 3.) Move the cutter outline to the home position with the [G]oto drawing command. Use the mouse to position the cutter outline near the edge of the raw material. Press the left mouse button to draw the first line segment in the tool path. Move the mouse for the path of the first cut and press [33] [ D R A W I N G T O O L P A T H F I L E S ] the left mouse button again. Continue drawing zig-zag, concentric, or spiral tool path until the blinking outline of the cutter comes in contact with the outline of the final shape. When drawing tool paths be sure that you only feed the amount that can be safely taken off (so the tool will not stall or break!) Also remember that some cutters can only cut going one way, so you may have to retrace without feed when drawing in one direction. Pressing [L] while inside the [D]rag command will let you change the drawing line color, and therefore set the feed rate, auxiliary relays, and programed pause. 6. When the tool path is finished press [Escape] to exit the [D]rag command. [Q]uit the drawing editor and select [F]iles [S]ave [A]SCII from the main menu. Enter the element number for the element of the tool path (normally element 3) as the element to save. 7. Make a trial part using DANPLOT or DANCAM. 8. Measure the trial part. Record any error in the final shape. 9. Load the tool path ASCII file into DANCAD3D and use the [P]ull- Point command in the [L]ines sub-menu of the drawing editor to alter the tool path line segments for the final cut, in order to correct the error. Save the corrected tool path element again as an ASCII file. 10. Repeat steps 7 to 9 if needed until the finished part is in tolerance. Make the run of parts as needed. Store the ASCII tool path file on a floppy disk for future use. You should also copy the DANPLOT.CFG or DANCAM.CFG file used to make the part onto the floppy with the tool path so the tool path will match up if used again. You should also file notes about the spindle speed and cutter seating used and also the location of the limit switches relative to the work-piece. If you want to change the line color attribute for any of the line segments in the tool path such as the line segment for the final cut you can use the commands in DANCAD3D's drawing editor [L]ines sub- menu. The conversion of the line color attributes in the tool path data file to feed rates is done using the values for the step delay that you have entered into the DANPLOT and DANCAM feed rate table (option #4 in the DANPLOT and DANCAM installation sub-menu.) You can also draw the bulk of the tool path in the drawing editor [D]raw lines sub-menu and then go into the [D]rag command in the [E]lements sub-menu to align the cutter outline to the final shape outline for the last few cuts. If you want to add line segments to the tool path element that you started in the [D]raw lines sub-menu use the [D]rag command as described above in step 5. but select command [E]lastic line in place of [B]egin element. When you need to use commands that create new elements such as the [34] [ D R A W I N G T O O L P A T H F I L E S ] [P]olygon command, or the [F]it-curve in DANCAD3D's, you can unite later the elements created into a single ASCII file by erasing the finished part outline, and the tool outline from the workspace, then use element 0 as the element to save rather than element number 3. The [J]oin command in DANCAD3D's drawing editors [E]lements menu can also be used to unite elements into a single tool path element. [35] [ R U N N I N G T H E C A M D E M O F I L E S ] RUNNING THE DEMO FILES FOR DANPLOT AND DANCAM A demo is provided for each program. Enter DEMOPLOT.BAT from DOS with the prompt indicating the drive and directory all the DANPLOT files are in. DEMOCAM.BAT does the same for DANCAM. EXAMPLE: C>DANPLOT DANPLOT.ASC 1 You can interrupt the motion of the motors momentarily by pressing the [P] key, press [P] or [SpaceBar] to restart the motors. If you need to touch or otherwise expose yourself to the equipment while the motors are paused from the keyboard you should also use the pause switch wired in series with the limit switches (as shown on drawing HOOKUP1.ASC) and turn off the motor power (if your translator module will re-initialize when the motor power is cut off you will have a problem (because the motors may jump when the power is switched back on), the circuit schmatics I provide with the DANCAD3D user outfit for the stepper motor translator allow the translator logic to stay powered while the motor coil (phase) power is switched on or off thereby avoiding any motor jumping.) You can load the example *.ASC tool path files into DANCAD3D to look at how they were drawn. DANCAD3D's main menu [P]review command will let you rotate the display of the tool path's line segments so you can see the spatial relationships. [36] [ H E L P W I T H D A N C A M A N D D A N P L O T ] HELP AND FEEDBACK If you have any questions or comments about DANCAM or DANPLOT feel free to write me at: ADDRESS: DAN HUDGINS c/o DANCAD3D CNC 466 DIAMOND STREET SAN FRANCISCO, CA 94114 The UNITED STATES of AMERICA When you write PLEASE enclose some stamps for the replay postage. If you live outside the U.S. you can get some postal vouchers for first class international air mail postage from your post office. More information and schematics for wiring up inexpensive motor driver modules is included in the DANCAD3D user outfit. I can help you design custom hardware special applications. If you need help in locating stepper motors, drivers, and other mechanical and electronic components feel free to contact me for help in locating just what you need. I am always on the look out for parts that are at the lowest cost. If you would like to discuss something on the phone I can call you collect if you send me a letter telling me what time to call and asking me to call collect (sorry but collect calls cannot be made to Germany.) I can call on evenings or weekends if you prefer, but be sure to tell me what days and times I should call. I am always working on a improvements to the programs and documentation. If you register with me by sending one dollar and your full name and address I will put your name on my user mailing list. If you are using DANCAM or DANPLOT at all you will benefit from communicating with me directly. If you have a machine hooked up I would be most appreciative if you could send me a photo of what you have built, I always enjoy seeing what users are doing with the programs. Feel free to send me your "wish list" for DANCAD and DANPLOT improvements. Although "G" codes are not needed since DANCAD3D makes tool paths graphically I may write a "G" code converter if enough users ask for me to write one. If you are interested in "G" codes send me a "G" code file on a floppy disk so I can see the type of file you need. [37]