WEAR YOUR CAUTION: The power cord SAFETY GLASSES receptacle in the control box is easily damaged. Plug and unplug FORESIGHT IS BETTER THAN NO SIGHT the power connector with care! READ INSTRUCTIONS BEFORE OPERATING NOTE: The power supply included with this indexer is intended to operate only on 115/120 VAC, 60 Hz (38 W) current. For countries operating on 100, 220 or 240VAC and/or 50Hz a transformer will be required. As an alternative, this power supply outputs 24VDC, 1 Amp (1000 mA). If you can purchase an appropriate power supply that operates on local current and outputs 24VDC, 1A current, it could be used to power CNC Rotary Indexer the unit instead of the one supplied. Sherline Products does not provide a 220V power P/N 8700 supply or transformer. accuracy that can be obtained in real terms. The stepper Installing and Using the motor takes 400 steps to make exactly one revolution. This Sherline CNC Rotary Table and Controller motor drives the worm, which needs to make 72 revolutions By Bryan Mumford and Joe Martin to make the rotary table turn exactly one revolution. This Introduction means that it takes 28,800 steps (400 x 72) to drive the Bryan Mumford, and we at Sherline, are very proud of this rotary table one complete revolution. Take this number and product. It has taken Sherline twice the investment in both divide by the number of degrees in a circle (360°) and we time and money compared to what we originally planned end up with 80 steps for each degree or 0.0125° (or 0.75 for this project. This project would have been a lot easier minutes) for each step. The built-in computer will calculate if we built the $4000 product that we are competing with. to the closest position. This means the final position will be We have taken a very expensive product that has only been within ± ½ step. This turns out to be a very small amount, available to very successful professional businesses and because the sine of this angle is only 0.0001091. This will produced a self-contained unit that not only has the features amount to 0.109" (2.77 mm) rise in 1000 (83- 4 or 25.4 m) of the expensive units, it is also simpler to use and very when compared to a flat plane. This is just .00022" (.0055 affordable. In fact, it is so inexpensive, home hobbyists can mm) at the edge of the table. now afford to own and use this equipment. It should also be Mechanical Accuracy noted that we didn’t copy anyone to accomplish this feat. The gear that turns electronic signals into a real movement The only disappointment was that we were unable to find has been hobbed directly into the table, which means the a way to adapt our existing rotary tables to a CNC unit. It teeth have been generated on a machine that cuts the teeth just couldn’t be done in a cost-effective manner because with a cutter similar to a worm as the part is turning. This of the mechanical parts that couldn’t be interchanged due eliminates any error associated with cutting each tooth to the way the rotary table is manufactured. individually. As anyone associated with the machine trades Even though the computer is small, it is a very complex realizes, “nothing is perfect”. This is also the case for this device that both computes and drives the stepper motor in product; however, we seriously doubt if anyone buying micro steps. Like all electronic devices, the easier it is to it could measure the mechanical indexing error of the operate, the harder it is to design and program. We believe worm and gear. The electronic system has no error in its the instructions are easy to read and shouldn’t give you any calculations, but it does round off as previously explained. problems, but if they do, please notify us at Sherline, and The Importance of Reading the Instructions we will attempt to improve them. We want our instructions It is impossible to make a product this complex “idiot to be the best in the business. The most important rule is proof.” The best rule when dealing with any type of CNC to always work safely and accurately. equipment is this: “You have to know what the unit will do Power of the Motor after you push the button BEFORE you push the button.” The stepper motor is rated at over 100 oz-in of torque, This can only be accomplished by reading the instructions with the highest power being achieved at low RPM. The and “playing with the rotary table” at the same time until maximum speed of 50°/sec provides high speed but very you thoroughly understand how the features of this unit little power. To use that setting for positioning, the system work. It isn’t necessary to understand the interfacing options must be completely free from drag. We recommend using a to safely operate the CNC rotary table. Don’t mount this maximum speed of 40°/sec as a positioning speed to avoid unit on a mill that has a cutter in the spindle until you truly stalling the stepper motor. When cutting, slow speed should understand how to control it. be used to take advantage of the motor’s power. Precautions when Turning on the Unit Positioning Accuracy • As with any piece of electronic equipment, make sure The first thing to understand about the rotary table is the the power is off before plugging the stepper motor connecting cord into the control unit. SHERLINE PRODUCTS INC. • 3235 Executive Ridge • Vista • California 92081-8527 • FAX: (760) 727-7857 4/24/19 Toll Free Order Line: (800) 541-0735 • International/Local/Tech. Assistance: (760) 727-5857 • Internet: www.sherline.com • If a part has been aligned on the table and the power is switched off; the part should be realigned after turning the unit back on before continuing. Electrical “spikes” can cause the motor to move a few steps when turning it on. The power can be left on continuously without damage; however, the controller should be left in “Jog” mode to prevent the motor from being 1 3 Stop JOG 2 JOG Jog energized. If you don’t do this, the motor may be left energized because the motor is electrically locked in position after a controlled move. Always record your Nxt handwheel settings at a “home” for future use. 4 5 6 Operating Instructions The Sherline Rotary Table Controller is a self-contained 7 9 Prv microprocessor-based controller that will automate the Slow 8 Fast motion of the Sherline rotary table. Though you can still crank the table by hand when in the jog mode or when the controller is turned off, the controller is designed to crank Minus 0 Enter Mode it for you in precise, measured steps. NOTE: We are stating the following weight limits for our rotary tables for continual use. FIGURE 1—The keypad layout Horizontal orientation—50 lbs. Vertical orientation—30 lbs. These commands are described in detail in the appropriate Vertical rotational torque—6 foot/lbs. (meaning it can lift a 6 lb. section if needed. weight when suspended 12" away from the center of the rotary table) The “Settings” Mode The rotary tables can hold more weight when they are not under a The next mode after the Program Mode is the Settings Mode. continual load. This allows you to enter some parameters of operation for the table. These settings are remembered even when you Precautions Regarding Manual Mode turn the controller off. When hand cranking the handwheel in the manual mode, Slow Setting the stepper motor acts as a generator. If you crank the When the screen displays: handwheel rapidly, there is a chance that the control box electronics could be damaged by the current generated. If Settings Mode the unit is to be used extensively in the manual mode, it is Press Enter recommended that you first turn off the power switch on Press the [ENTER] key. The screen will then display the control box and then turn the handwheel no faster than something similar to: 1 rev/second. Physically unplugging the unit each time is not necessary and can put undue stress on the plug itself Slow: 15 causing a poor connection and eventual short circuit. Enter a number NOTE: You can skip over the Start-Up and Settings The number after the word SLOW is the minimum feed rate Commands if you are reading this for the first time. The of the rotary table. This is the speed with which the table factory default settings will work, and these settings are starts each movement. The units are degrees per second. only needed for advanced operations. Whenever the table moves, it starts at the SLOW feed rate Start-up Commands and ramps up to the FAST feed rate. It also ramps down to the SLOW rate before stopping. There are several utility commands that can be issued by holding down certain keys when the controller is first When the screen shows the value you wish to use for turned on. For example, to enter the SLAVE MODE (to run SLOW, press the [ENTER] key. The value will be stored the controller with STEP and DIRECTION signals from and remembered for all future operations and used with another CNC controller) hold down the [ 1 ] key when you the JOG, DEGREES and DIVISION modes. first turn the controller on. Fast Setting The four start-up commands are: The screen will then display something similar to: [ 1 ] - Enter “Slave” mode.