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    1 v1.1a Changes and additions v1.0c—Added 10/9/03—Page 66, Supplemental information for loading Sherline version of EMC when using with 8760 driver box. Page 13, Using these instructions for a lathe. V1.0c—Added 11/13/03—Minor change to line one of coding on page 66. “/” symbol adde...

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    2paper tape) was a tracing system that duplicated parts by tracing them with a hydraulic system controlled by a really neat valve controlled by a stylus that the operator would move like a probe and the machine would duplicate their movements. Gigantic machines were built around this idea for t...

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    3about 0.187" (5mm) would engage the proper hole and then another plate with holes spaced at 0.200" would come into play, and the last 0.200" relied on a single turn of a lead screw. The machine finally arrived at a position within a 0.001" of accuracy. I didn’t realize it...

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    4into a shaft at a pitch of two tenths of an inch. The pitch on these screws has increased over the years to achieve speeds over 1000 inches (25 meters) per minute. At a pitch of .200″ (5mm), a lead screw would have to turn at 5000 RPM to accomplish this speed, which is why ball lead screws h...

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    5Even though this doesn’t do the subject justice I thought you might find that interesting. It’s always wise to see at least a brief history of a subject before becoming part of it, even if it’s only statistical. Here is something I wrote in my book that’s available online that you may ...

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    6don’t. The products get more complex, making the instructions more complex, and the poor consumers of these products are at a loss. I don’t teach using these methods because they obviously don’t work. With my instruction you won’t be sure if you’re reading a novel or an instruction m...

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    7machining process, and I believe I’ll help get your brain in tune with what you are about to learn with my ramblings. Learning while you work A student of this class could be already working at the trade. Words of advice for this group: You can’t afford to have idle thoughts as you load pa...

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    8I’m going to be a student in my own class I was shocked at just how much I had forgotten about the process of CNC programming. I probably know as much as anybody of what you can do with CNC machines, because I own at least twenty modern machining centers, yet I haven’t really written any c...

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    9codes can be read throughout the world. G-code standards came about very early in the game because this game was controlled by engineers rather that marketing people. Contouring programs, another world Programs that allow you to do contouring quickly become very complex. Today there are some a...

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    10double click to enter a program, so a single click on the big red “S” (Sherline, not Superman) with the file name “inch_freq” underneath, and after a few seconds you’ll get the graphical interface to the EMC. Well, that was easy. Now, after BS-ing you to death on how hard this was t...

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    11I can’t help anyone who isn’t willing to work hard Back in ancient times the great mathematician Euclid told a Pharaoh who wanted to learn geometry the easy way that Pharaohs had to walk down the same road as scholars to education. In a sense I’m also stating to you that you will have t...

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    12I’m fascinated with the program because it does a drawing without errors when used properly. The program eliminates much of the boredom of adding and subtracting numbers as you go. Accuracy isn’t attained by the precision of your lines but rather by the accuracy of the information the pro...

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    13leadscrews, leadscrew nuts and bearings that are subject to high wear due to continuous usage are not covered under this one-year warranty. Non-warranty service and machine tune-ups Sherline machines are easy to service, and all replacement parts are available from the factory. However, if in...

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    146. Avoid a dangerous work environment—Do not use power tools in damp or wet locations. Keep your work area well illuminated. 7. Keep children away—All visitors should be kept a safe distance from the work area. 8. Make your workshop “kid-proof” —with padlocks, master switches or by ...

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    1523. Disconnect the computer from all power sources before opening case—With the computer power switch off, some of the internal components of your computer are still electrical hazards and can provide a severe electrical shock. Disconnect the computer from the power source before opening th...

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    16is changed. If multiple holders are used, each with its own tool pre-adjusted to the correct height, tools can be interchanged quickly with excellent repeatability on their height setting. One hour of free consultation Included in the purchase price of your Sherline CNC mill was one hour of ...

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    17 System components: 1) 1-5/8" manual handwheel 2) Z-axis stepper motor 3) Stepper motor mount 4) Sherline vertical mill with drill chuck, headstock spacer block, hex adjustment keys and spindle bar 5) Backup Linux/EMC installation CD, Sherline instructions CD and Vector32 CAD program CD...

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    18 Connections on back of your computer: 1) Keyboard connector cable (purple) 2) Mouse connector cable (green) 3) Computer power switch 4) Connector from driver board to parallel printer port 5) Power cord 6) Connect your monitor here (blue) 7) On/Off switch for driver power supply 8) Output...

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    19Unpack the computer and enclosed components. Connect the stepper motor cables leading from the back of the computer to each of the three stepper motors. A fourth cable is unused unless you have purchased an optional rotary table that can be connected here as a 4th (A) axis. Plug the purple ke...

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    20By default your Sherline CNC system works in inch dimensions. Should you wish to use metric dimensions to program your machine, even though it has an inch leadscrew, you can do so by entering the code g21 in place of the g20 code when writing the program for your part. G20 indicates inch incr...

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    21Below the menu line is a line of control buttons. These are the primary control buttons for the interface. Using these buttons you can change mode from [MANUAL] [AUTO] [MDI] (manual data input). You can also use [FEEDHOLD] or [ABORT] to stop or abort a programmed move. When you press the [FEE...

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    22Feedhold and Feedrate Override You can operate feedrate override and feedhold in any mode of operation. Override will change the speed of jogs or feedrate in manual or MDI modes. A feedhold will be initiated if you click the [FEEDHOLD] button or if you press the pause button on the keyboard. ...

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    23The EMC can jog (move a particular axis) as long as you hold the button down when it is set for “continuous,” or it can jog for a preset distance when it is set for “incremental.” You can also jog the active axis by pressing plus [+] or minus [-] keys on the keyboard. Again, case is n...

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    24The number buttons along the top of the main keyboard will change feed rate whenever you are in auto mode. Pressing the gravé [`] gets you zero percent feed rate. One through zero gets you ten through 100 percent feed rate. These keys can be very handy as you approach a first cut. Move in qu...

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    25active g-codes. This listing can be very handy. I often forget to enter a g00 before I command a motion. If nothing happens I look down there to see if g80 is in effect. G80 stops any motion. If it’s there I remember to issue a block like g00 x0 y0 z0. In MDI you are entering text from the ...

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    26coolant creating more problems than they eliminate. The Sherline mill is fitted with “Hard Stop” screws on the X and Y axes that limit travel. These stops are the heads of cap screws fitted to the table and base and positioned to stop a runaway axis without damage. If you make a programmi...

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    271) To create a new file or work with any existing programs we have to be in the [AUTO] mode. Notice that a new line of commands appears along the bottom in this mode. The [Open] button is located in the along this row. Note: the method I’m describing in A) to E) below is to set up your comp...

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    28E) Next, highlight (with the mouse button held down drag the cursor across the entire area you wish to highlight) and delete (press enter) the existing program with your mouse. Replace that program by typing “Save as another file name.” This will remind you to only use the “0-new” pro...

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    29Although there is quite a bit of well-written instruction on how to program on the Linux CNC site, I believe you should only go there to learn beyond the limits of my instructions. Having too many instructors on a subject that you know nothing about isn’t a good idea at this time. At the en...

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    30control function, direction or speed and, in general, cannot be used in the same line of code with other modal g-codes for obvious reasons. g00 rapid positioning g01 linear interpolation g02 circular/helical interpolation (clockwise) g03 circular/helical interpolation (c-clockwise) g04 dw...

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    31The entire program: % (g02 circle program) g01 g90 x0 y0 z0 f2 g02 x0 y0 i-.5 j0 g01 g90 x0 y0 z0 f2 % 1) % –Always start a new program with a % sign. This informs our robot that a program is coming in. Each time you press [Enter], the program will start a new line, so [ENTER] it is, and w...

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    32B) The g02 the program needs the x, y position entered as to where this arc will end, and since we are creating a circle it obviously will end where it started so the present position is entered. C) Here are a couple of new commands; i and j, and they are used to describe the center location ...

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    33times and take the time to really understand what’s going on. From the control panel you can single step the program through and run things until you’re bored. You had your fun and it’s time to go to school again. Now guys and girls, it’s time to go back as many times as it is necessa...

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    34 Figure 1 If you’re reading this, I’ll assume you passed the test, so now take your second test by erasing your program with the backspace key and doing the entire exercise over from memory. Meet Millie Think about what you accomplished at this point. You’re beginning to understand how...

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    35computer to use the tool length (h) stored in the line (1,2,3,---) of the tool data file. A g49 is entered when the z-axis is brought back to its home position to cancel out the tool length compensation that was called up when you first started using the tool. From a practical standpoint, I l...

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    36 Figure 2 If you firmly imbed this into your mind, you’ll save the many hours of wasted time that I spent learning it. Of course I knew that this is impossible, but I kept asking my computer to do it when I was entering the cutter offset mode. As soon as a g41 or g42 is entered into the pro...

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    37a message. What we want to accomplish is approach the starting point in two separate moves so that we are coming into the part like a plane on final approach to an airport. The plane flies to the first point, where it lowers it landing gear (g41—a move where the cutter comp is entered durin...

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    384) g42 d1 x.5 y1 –End Mill (aircraft) approaches part as tool compensation is entered (gear down). d1 will define the offset as it moves to this new g42 position. We’re still traveling too fast for landing. 5) x0 – We’re directly above the touchdown area and come to a halt. 6) z0 –...

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    39The entire program: % (cut rectangle with cutter comp) g00 g90 g40 x1 y0 z1 z-.140 y.090 g41 d1 x.5 g01 x0 f10 x-1.910 y1.910 x-.090 y.100 z-.150 x-1.900 y1.900 x-.100 y.100 x-.200 y-.200 g00 g40 z1 x1 y0 z1 % Nothing worth commenting about in that program except that my final move before ca...

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    40 Figure 4 The entire program: % (atomic circle) g90 g17 g40 g00 x0 y0 z0 g03 x0 y0 i0 j1 f100 g02 x0 y0 i0 j-1 g03 x0 y0 i1 j0 g03 x0 y0 i-1 j0 g18 g03 x0 z0 i0 k1 g02 x0 z0 i0 k-1 g03 x0 z0 i1 k0 g02 x0 z0 i-1 k0 g19 g03 y0 z0 j0 k1 g03 y0 z0 j0 k-1 g02 y0 z0 j1 k0 g03 y0 z0 j-1 k0 g90 g17 g...

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    41The Great Race Let’s go PC aircraft racing instead of R/C. First, set the tool diameter D1 to .600". Next, we’ll lay out a triangular course. Our micro delta racing aircraft have strange flying characteristics allowing them to fly forward and backward in a nose down attitude. (Somet...

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    42z0 y.5 g00 x-1.6 y.8 g01 y1.8 f100 (course complete) (Taxi to starting line) x-1.6 y1.3 f15 m00 This will pause the program while you get ready to set your stop watch. To start the race you’ll have to use [Resume] button because the [Run] button will not restart the program when it is in a...

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    43x-4 y1.5 g03 x-4 y.5 i0 j-.5 g01 g90 x-2 g18 g02 x-2 z1 i0 k1.5 g01 g90 g17 x2 g02 x2 y-.5 i0 j-.5 g01 x-2 z0 f20 x-2.5 z.15 f15 x-3 z0 f10 x-3.2 z.1 f5 x-3.4 z0 x-3.6 z.05 x-3.7 z0 g03 x-3.7 y-.9 i0 j-.2 g01 g90 x-1 f25 g03 x-.5 y-.4 i0 j.5 f15 g01 y.5 g03 x-1 y1 i-.5 j0 g40 g90 g00 x-1 y1 z...

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    44 Figure 6 I cheated and used AutoCad®… y1.373 (lap 4) x-3.862 y.961 x-1.123 y.578 y1.373 (lap 5) x-3.862 y.961 x-1.123 y.578 y1.373 x-1.6 (race over) –We won g40 x-3.5 z1 –Turn off the navigational aid and climb out x-4 y1.5 g03 x-4 y.5 i0 j-.5 – A nice lazy fast turn g01 g90 x-2 g1...

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    45g03 x-3.7 y-.9 i0 j-.2 –Let’s get out of here before they remember me for that lousy landing g01 g90 x-1 f25 –A nice fast taxi home g03 x-.5 y-.4 i0 j.5 f15 g01 y.5 g03 x-1 y1 i-.5 j0 g40 g90 g00 x-1 y1 z0 –Home at last. I wonder if they’ll remember my lousy landing more than our wi...

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    46There isn’t any sense in entering the next section unless you can easily write these programs. If not, go through that section again and again until it is second nature. Back to school We’re on the move again and leaving route g41 for a while, but I’m sure we’ll return. We are headed ...

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    47work in unison with the computer. It has nothing to do with the accuracy you require, but only with what our loyal computer requires. I dug out my old calculator to solve these problems and then checked my answers against what I had already calculated in AutoCad®. I’m going to assume you w...

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    48 Figure 10 First, what two things do we have to solve this triangle? We have the hypotenuse because it is the radius of the arc and the 5° angle. From our tables we see that the 0.0436 was derived by multiplying the hypotenuse (0.5) times the sin 5°; and the 0.4981 was the product of 0.5 x ...

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    49 Figure 11 This program is just an exercise, and I’m not going to write any Z-axis code. The 0 starting point is located in the upper right-hand corner. Of course, we’ll also use cutter comp to generate this shape. Now, read the code I wrote and examine Fig. 11 again and visualize where t...

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    50x.5 g00 g40 g90 x0 y1 z0 % With comments % g00 g40 g90 x0 y1 z0 g41 d1 x0 y.5 g01 y0 f16 Last time, I started at y1 position so I could enter into the cutter comp mode in two moves and coming in from the correct direction (remember - gear down-touch down). y-2.000 x-1.7032 g03 x-2.2013 y-2.4...

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    51 Figure 13 Here is the real problem. The seemingly obvious way of solving this problem would be to solve the angle that can be generated with the differences between the radii and the distances between centers and then use this information to come up the needed points. Wrong. Compare the two ...

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    52Believe me, I studied this problem for a long time before I was able to solve it. I also came up with unusually simple way to arrive at the second side of the right triangle so the problem was solvable. I don’t want to blow my own horn, but it is extremely rare that an individual like mysel...

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    53Let’s write the code for this simple yet not-so-simple shape. One thing I must state again is that I’m having a terrible time with careless errors. I think the problem is that I’m more worried about how I’m going to explain each problem than I am in entering the correct numbers. Don...

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    54When you have to solve a problem like this, the first thing you have to do is determine what you have to work with. In this case, we know the two radii of the arc and the width of the straight section leading to it. Studying the drawing you will find that with the information known there is o...

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    55Now let’s write the code for this beauty. Also, I added a couple of Z-axis movements that might be used in the real world. % (rod-end) g00 g40 g90 x0 y0 z0 g41 d1 x-.75 y-.25 g01 x-1 y-.25 f25 z-.5 x-2 g03 x-2.2412 y-.3716 i0 j-.3 g02 x-2.2412 y.3716 i-.5025 j.3716 g03 x-2 y.25 i.2412 j.178...

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    56command, and that’s the type of systems that many beginners will end up running. You will see in the rod program just how much tedious code writing it eliminates. % (Connecting rod) g00 g90 g40 x0 y0 z0 g01 x-1 y.5 g41 d1 y.1 g01 y0 f15 g02 x-1.5638 y-.1858 r.3125 g03 x-1.6844 y-.125 r.15 g...

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    57 The Sherline 8730 CNC Rotary Table with stepper motor can be plugged directly into the A-Axis cord pre-wired into your computer to operate as a 4th axis. --------------------------------- Conclusion You’re ready to take off on your own The next stop on the EMC highway is to visit Linux-CN...

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    58to donate a few dollars to my foundation that is dedicated to getting great craftsmen the respect they deserve in this world. Check out actionURI(http://sherline.com/jmfound.htm):http://sherline.com/jmfound.htmactionURI(http://sherline.com/jmfound.htm): and be sure to visit the Joe Martin Fou...

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    59Table 2—M Word List M0 program stop M1 optional program stop M2 program end M3 turn spindle clockwise M4 turn spindle counterclockwise M5 stop spindle turning M6 tool change M7 mist coolant on M8 flood coolant on M9 mist and flood coolant off M26 enable automatic b-axis cl...

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    60Tool diameter compensation (g40, g41, g42) and tool length compensation (g43, g49) are covered Table 4—G- and M-Code Modal Groups Group 1 = {g0, g1, g2, g3, g80, g81, g82, g83, g84, g85, g86, g87, g88, g89} —motion Group 2 = {g17, g18, g19} — plane selection Group 3 = {g90, g91} - ...

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    61Language: Next you will see the graphical portion of the installer, and it will ask you to select a language. It defaults to English, but if you happen to be using another language select it and press [NEXT]. Keyboard and Mouse selection: You should be using the keyboard and mouse that came w...

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    62insert the Sherline EMC disk into your computer that you have transferred programs and data to another computer that you want to save. Your hard disk will be completely overwritten with the Linux operating system. Installation is simply putting the CD into your computer and rebooting on most ...

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    63BDI and the EMC. Let’s run a quick experiment so that we know how your PC wants to boot. Turn off the PC. Place the BDI disk into the CD-ROM and turn it back on. If you see “Welcome to the Brain Dead Install for EMC” at the top of the screen after a bit, you’re there and you should sk...

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    64Rawrite said, “Enter disk image source file name:” I answered, “E:imagesboot.img” Rawrite said, “enter target drive:” I answered, “A:” Rawrite said, “Please insert a formatted diskette into drive A: and press [Enter]:” I did that and after a minute or two the terminal wind...

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    652.2.3 Mouse If this is a PS-2 mouse—the one with the little round connector that plugs directly into the back of the computer—you should be able to get by with either a 2 or 3 button generic definition. A serial mouse may not be recognized during the graphical install, and you may want t...

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    662.2.9 X-Configuration There are a couple of screens here. I'll lump them together in this section. One caution, don't be in a big hurry to get past this. X is the name of the window manager that is used with the BDI. Like MS-Windows, X-Windows is a way of making your monitor display picture...

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    67Supplemental guide for installing Sherline modifications when using the 8760 driver box package If you are reading these instructions and have purchased a Sherline 8760 (A CNC External Driver Box) rather than a complete system with computer, you may be wondering why a Sherline logo mentioned...

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    68system. They show you how to plug in your new Sherline CNC computer and stepper motors. You can see these instructions in several places. In addition to the printed sheet, it is on your Sherline Documentation CD where it is called quickstart.htm. Here you can see photos of the system and the ...

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    69average Linux users and a handful of very talented coders. You can get up to date on the project and get more detail on the movement of it by reading its website actionURI(http://www.linuxcnc.org/):http://www.linuxcnc.org. What programming language does the EMC system use? The Sherline CNC s...

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    70 How do I transfer my g-code files to my CNC computer from my CAD/CAM computer? There are a few ways you can do this, but the easiest way is to put your g-code text files onto a floppy disk or write them to a CD on your CAD computer, then take the floppy disk or CD and put it into your Linux ...

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    71Other than calling Sherline, where are some places I can go to get help on my specific questions on machining, CNC and using Sherline tools? Sherline owner discussion groups can be found at actionURI(http://www.yahoogroups.com/):http://www.yahoogroups.com. Just go to the yahoogroups.com web s...

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    72tar zxvf sherline-mods.tar.gz rpm -i --force emc-rtl3.0-2.18.i386.rpm rm -fR /root/Desktop/emc_* (Though it can be hard to see, there is a single space after “cp”, “cd”, “tar”, “rpm” and “rm”—the first items in each line above. There is also a single space after “-i”...

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