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[[Category:CNC_Mill]]
[[Category:CNC_Mill]]
===Type===
Appears to be a [http://www.taigtools.com/cmill.html Taig CNC Mill].


Currently running EMC2/Axis 2.4.6.
=Type=
[[File:TAIG_CNC_Mill.JPG|frame|http://www.taigtools.com/cmill.html]]


=== Terms ===
Our CNC mill is a [http://www.microproto.com/MMDSLS.htm MicroMill DSLS 3000], a [http://www.taigtools.com/cmill.html Taig Manufactured CNC Mill].
 
This mill is generously on loan from the Smithsonian.
 
We are running [http://www.machsupport.com/ ArtSoft Mach3] for control software.
 
=Terms=


* Computer Numerical Control (CNC) - The ability to control a machine using mathematical commands
* Computer Numerical Control (CNC) - The ability to control a machine using mathematical commands
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* Manual Data Input (MDI) - A method for doing manual milling with precise control commands.
* Manual Data Input (MDI) - A method for doing manual milling with precise control commands.
* Lathing - The use of a "static" piece of metal to shape an object through calculated removal of a media which is in (usually) a circular motion.
* Lathing - The use of a "static" piece of metal to shape an object through calculated removal of a media which is in (usually) a circular motion.
* [http://www.linuxcnc.org EMC2] - The software used to translate G Code into electrical pulses which can be used by a mill.
* [http://www.machsupport.com/ Mach3] - The software used to translate G Code into electrical pulses which can be used by a mill.
* [http://www.linuxcnc.org/docview/html/gui_axis.html Axis] - The most commonly used graphical user interface with the program EMC2


=== Getting Started ===
=Getting Started=


To initially get started with the CNC mill, it's helpful to have a basic grasp of G Code.  How better to get started with this than to begin playing.
To initially get started with the CNC mill, it's helpful to have a basic grasp of G Code.  How better to get started with this than to begin playing.


==== Turning on the Mill ====
==Turning on the Mill==
When turning on the mill there are three primary "light switch" style switches which should be turned on.  The first is on the back of the black box labeled "MicroProto Systems, MicroMill DSLS 3000".  This switch is located on the back to the right side (imagine reaching around on the rear right).  Flipping the switch "up" should turn this on.
When turning on the mill there are three primary "light switch" style switches which should be turned on.  The first is on the back of the black box labeled "MicroProto Systems, MicroMill DSLS 3000".  This switch is located on the back to the right side (imagine reaching around on the rear right).  Flipping the switch "up" should turn this on.


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To avoid unexpectedly turning on the spindle motor when powering on the machine, wait to flip the power switch to the on position until after EMC2 is running. This will ensure that the parallel port is in the appropriate state according to the configuration file to keep all motors off by default.
To avoid unexpectedly turning on the spindle motor when powering on the machine, wait to flip the power switch to the on position until after EMC2 is running. This will ensure that the parallel port is in the appropriate state according to the configuration file to keep all motors off by default.


==== Starting EMC2 ====
==Starting Mach3==
To start, you'll want to fire up EMC2 with the proper configuration file.  This can be done by using the icon on the desktop or by clicking the corresponding link on the quick launch bar on the top of the screen.
This can be done by using the icon on the desktop.
 
==Spindle control and Emergency Stop==


If the mill has been turned on and the right configuration file is used, you will hear the spindle briefly spin up.
If the tooling is clear of all obstacles, you can press ''F5'' to toggle the spindle motor on and off.  


Once in EMC2 you'll need to enable machine control of the mill. Begin by clicking the large red "X" button on the button toolbar within AXIS. After this button has been pressed, the power button directly beside it should become available to click. Upon pressing this "power" button, EMC2 / AXIS can be used to send commands to the mill.
The switch on the right side of the mill, near the top will cut power to the spindle. This is the best way to shut it down in an emergency... but note that the axis can still move after the switch is thrown. Pressing ''Reset'' in the interface will signal Mach3 to make an ''Emergency Stop''. You'll see the ''Reset'' button blink, and the status line at the bottom will read "E-Stop Triggered, press reset...".


==== Making our first motions ====
==Making our first motions==


===== Beginning Manual Control =====
===Jog Controls===
To start, we're going to use the "jog" functions to move the milling cutter around and get a feel for what is "positive" and "negative" on the X, Y, & Z axis.
To start, we're going to use the "jog" functions to move the milling cutter around and get a feel for what is "positive" and "negative" on the X, Y, & Z axis.


Especially, when starting out, limit motion to the X and Y axis as this has the least potential for damaging our tooling (aka, breaking a bit).  As you get a feel for what's positive and negative, we will start using larger motions.
Especially, when starting out, limit motion to the X and Y axis as this has the least potential for damaging our tooling (aka, breaking a bit).  As you get a feel for what's positive and negative, we will start using larger motions.


To start, hit "F3" on the keyboard to enter fully manual control. This will present us with a radio button to choose the axis, followed by a "+" and "-" sign to show where our milling cutter will move.
To start, hit the "tab" key to bring up the Jog controls. The main settings on this panel are the ''Jog mode'', which can be either ''continuous'' or ''step''. In continuous mode, holding down the motion keys (described below) will make the axis move continuously, and quite a lot. In step mode, pressing or holding the motion keys will move only a fixed step per key-press. The step distance is also configurable on the Jog control screen. You can hide the jog controls when not in use by pressing the ''Tab'' key.


To start, select the "X" axis and press the positive button.  Next, select the "Y" axis and press the positive button.  As you were moving the milling cutter around, you'll notice that the coordinates are displayed in the preview window.  This is where you can quickly survey where your tooling is located.  Using these tools, move the mill to the following positions (x,y) - (0,0), (0,1), (1,1).
To start, select continuous mode in the jog controls and press the ''Left Arrow'' and ''Right Arrow''. Notice that the mill table moves left and right. This is the X axis.  Next, press the ''Up arrow'' and ''Down Arrow'' keys briefly, notice that the mill table moves front to back. This is the Y axis. Finally, press the ''Page Up'' and ''Page Down'' keys briefly; notice that the spindle moves up and down. This is the Z axis.  As you were moving the milling cutter around, you'll notice that the coordinates are displayed in the main window.  This is where you can quickly survey where your tooling is located.


Next, lets raise the tool a little bit to give ourselves more clearance to put in something to be milled.  Select the Z axis and press the "+" button.  Move the Z axis all the way to "1". 
===Obligatory Setup===


At this point, adding our Z axis, our tooling should be located at (1,1,1).
Sometimes the ''Reset'' button in Mach3 will be flashing. This usually means that you exceeded the movement limits or speed of the mill and the controller has signaled Mach3 to stop. Often clicking reset is enough to clear this error.  


===== Obligatory Setup =====
===Mill Controller Crash===
EMC2 requires axes to be homed before executing gcode (including Manual Data Input). To do this, simply click "Home Axis" under the "Manual Control" tab.


Sometimes, the desired origin point (x, y, z axes all at 0) will be different than the current position. To correct, jog the mill to the desired origin position, and click "Touch Off" under the "Manual Control" tab.
Sometimes the controller will crash, this is usually evidenced by ''Reset'' complaining that it cannot clear a limit. It will offer a button that says "Fix this for me". "Fix this for me" actually redefines what an error is in the software (e.g. if input low is defined as an error, then it will redifine error as input high). Instead of clicking ''Fix this'', you should try turning off and on the mill controller using the switch on the rear, lower-right side. Clicking ''Reset'' again should clear the trouble.


===== Advanced Manual Control - MDI (Manual Data Input) =====
===Advanced Manual Control - MDI (Manual Data Input)===
In AXIS press "F5" and go to the MDI Section.  Within this section we can type in actual G Code to move our tooling around.  To start, we're going to use simple "go to" commands.  This will rapidly move the tool to the position that we tell it to.  Note, at any time, we can stop the execution of these commands by hitting the "esc" key on the keyboard.  The first command we will use is "rapid go to" or "g0"
Click on the MDI tab in the main Mach3 screen to the MDI Controls section.  Within this section (the line next to input) we can type in actual G Code to move our tooling around.  To start, we're going to use simple "go to" commands.  This will rapidly move the tool to the position that we tell it to.  Note, at any time, we can stop the execution of these commands by hitting the "stop" button on the screen or typing ALT-S on the keyboard.  The first command we will use is "rapid go to" or "g0". As an example: make sure the tooling is well clear of the table using the jog controls and all axis are (roughly) centered. Reset all axis (X, Y, Z) to zero using the ''Zero Axis'' button located to the left of the current axis location. As you click zero axis, you should see the axis change to -0.0000.


To make our first motion, let's move the X axis to position 0.5.  To do this, enter the command:
To make our first motion, let's move the X axis to position 0.5.  To do this, enter this command into the box marked ''Input'':


   g0 x0.5
   g0 x0.5


The X axis should begin moving.
The X axis should begin moving and it should stop 0.5" to the right of it's initial position.


Additionally, we can give multiple coordinates at once.  Now try the command:
Additionally, we can give multiple coordinates at once.  Now try the command:
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To have more fine grained control we can use the command "g1".  There is nothing that G0 does which G1 cannot.  The only difference in syntax is that we specify the feed rate of the motion as the first option.  By default the mill is set to operate in inches per minute.  Thus, unless you change this (via g code) it should be assumed that this will be the unit of measure for your commands.
To have more fine grained control we can use the command "g1".  There is nothing that G0 does which G1 cannot.  The only difference in syntax is that we specify the feed rate of the motion as the first option.  By default the mill is set to operate in inches per minute.  Thus, unless you change this (via g code) it should be assumed that this will be the unit of measure for your commands.


Lets slowly drop our Z axis back to zero:
Lets slowly raise our Z axis up one inch:


   g1 f2 z0
   g1 f2 z1


Note, since we were at a position approx 1 inch up and told the mill to return to zero at a rate of F2 or 2 inches per minute, it will take approximately 30 seconds for this command to complete.  Slow movement of the tool (especially when 'plunging' the z axis is a good idea as it allows for time to hit the "esc" key if things start going horribly wrong).
Note, since we were at a position approx 1 inch up and told the mill to return to zero at a rate of F2 or 2 inches per minute, it will take approximately 30 seconds for this command to complete.  Slow movement of the tool (especially when 'plunging' the z axis is a good idea as it allows for time to hit the "esc" key if things start going horribly wrong).
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When moving back to zero you will see that the mill is moving half of the original speed (5 inches per minute rather than 10 inches per minute).
When moving back to zero you will see that the mill is moving half of the original speed (5 inches per minute rather than 10 inches per minute).


Let's really open this thing up and see what it can do.  While watching this command move notice the "vel: " or Velocity property in the preview window.  This will allow you to see the actual speed of the tool.
Let's really open this thing up and see what it can do.  While watching this command move notice the ''feed rate'' indicator in the preview MDI tab.  This will allow you to see the actual speed of the tool.


   g1 f50 x1 y1 z1
   g1 f50 x1 y1 z1
Hmm, apparently our steppers max out at ~10.39 inches per minute.  Thus, no matter how much faster we tell them to go, they will never go faster than this.


Linear motion is great and all, but how about we dwell outside the euclidean space for a minute.  The next commands that we are going to learn are G2/G3.  G2 will make a clockwise arc while G3 will make a counterclockwise arc.  The command syntax is as follows:
Linear motion is great and all, but how about we dwell outside the euclidean space for a minute.  The next commands that we are going to learn are G2/G3.  G2 will make a clockwise arc while G3 will make a counterclockwise arc.  The command syntax is as follows:
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Fun math bits... run that command again and note the "distance to go" or "DTG" in the preview area.  Note the distance at the immediate start of plotting our 1 inch diameter circle (2 * 0.5 X offset). This should be a predictable [http://en.wikipedia.org/wiki/Pi result]
Fun math bits... run that command again and note the "distance to go" or "DTG" in the preview area.  Note the distance at the immediate start of plotting our 1 inch diameter circle (2 * 0.5 X offset). This should be a predictable [http://en.wikipedia.org/wiki/Pi result]


===== Spindle Control =====
=Tool Changing=
The spindle motor only goes in one direction at one speed, however, EMC2 may require the spindle speed to be set before using it. Set to 10000 RPM.
 
  S10000
 
Only run the following commands IF the mill is not about to grind something undesirably (start with the Z axis high in the air).
 
  m3
  m5
 
These start and stop the mill, respectively.
 
=== Tool Changing ===
Use a wrench to gently remove the chuck. Check the toolbox beneath the mill for different bits and other things as required.
Use a wrench to gently remove the chuck. Check the toolbox beneath the mill for different bits and other things as required.


Little force should be required to tighten the chuck; it has been said that finger-tight is often sufficient.
Little force should be required to tighten the chuck; it has been said that finger-tight is often sufficient.


=== When you're done ===
=When you're done=
Be a dear and reset the mill back where you started.  Go into MDI mode and run:


  g0 x0y0z0
Please cleanup the mill area and place tooling back into the mill toolbox under the bench.


Finally, turn off all three power switches noted above.
Finally, turn off all three power switches noted above.
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Thanks
Thanks


=== GCode Tips ===
=Caution=
 
Jogging the mill is a pain in the ass.  One of the most helpful GCode commands you can use is "go to coordinate".  To go to an X coordinate "zero" one would use "g0 x0", similarly to go to y0 one would use "g0 y0".  This is especially helpful for moving the tooling out of the way to add a new piece to be milled or to make an adjustment.  Subsequently, the tooling can be reset with "g0 x0" "g0 y0" "g0 z0"
 
 
=== Config File ===
 
Redbeard made some changes to the config file including resetting the initial home positions to "0 0 0 0" so that when the application starts up, it will leave the tool exactly where it is placed.  While this isn't the behaviour we want long term, it's perfect for our current lack of limit switches.  Additionally, the directive "no_force_homing=1" was added to get rid of pesky error messages (again, since we don't have limit switches for homing the device.)
 
=== Caution ===
Please avoid doing these things, unless you can deal with the consequences yourself.
Please avoid doing these things, unless you can deal with the consequences yourself.


* Don't loosen the screws on the mill table. That wooden board must be precisely leveled, which can only be done by CNC milling it down.
* Don't run the mill too far off axis. The stepper motors will usually make a harsh grinding sound when this happens.
* Don't run the mill too far off axis. The stepper motors will usually make a harsh grinding sound when this happens.
* Don't leave the mill completely unattended. Be prepared to hit the F1 key within at most a minute of hearing something go wrong.
* Don't leave the mill completely unattended. Be prepared to hit the ''Reset'' key within at most a minute of hearing something go wrong.
* Obviously, don't put your hands in hazardous places.
* Obviously, don't put your hands in hazardous places.
Otherwise, the mill is robust and newbie friendly.

Latest revision as of 20:43, 14 February 2016


Type

http://www.taigtools.com/cmill.html

Our CNC mill is a MicroMill DSLS 3000, a Taig Manufactured CNC Mill.

This mill is generously on loan from the Smithsonian.

We are running ArtSoft Mach3 for control software.

Terms

  • Computer Numerical Control (CNC) - The ability to control a machine using mathematical commands
  • Computer Aided Design (CAD) - Software which generates a model which a machine can translate into tooling commands for manufacturing.
  • Computer Aided Manufacturing (CAM) - The actual process of production from file to finished product.
  • Tooling/tools - The bits used in a mill to actually
  • Milling - The use of a spinning piece of metal to shape an object through calculated removal of a media, normally via an X / Y / Z axis.
  • Manual Data Input (MDI) - A method for doing manual milling with precise control commands.
  • Lathing - The use of a "static" piece of metal to shape an object through calculated removal of a media which is in (usually) a circular motion.
  • Mach3 - The software used to translate G Code into electrical pulses which can be used by a mill.

Getting Started

To initially get started with the CNC mill, it's helpful to have a basic grasp of G Code. How better to get started with this than to begin playing.

Turning on the Mill

When turning on the mill there are three primary "light switch" style switches which should be turned on. The first is on the back of the black box labeled "MicroProto Systems, MicroMill DSLS 3000". This switch is located on the back to the right side (imagine reaching around on the rear right). Flipping the switch "up" should turn this on.

Next, turn on the main control to the spindle. This is achieved via the light switch on the M3/M5 box. Turn this to the "on" position (flicking it towards the label M3/M5).

Finally, turn on the spindle on the actual mill. This is in a blue enameled box residing on the Z axis. Flip this switch "up". If the spindle immediately starts spinning, this is because someone didn't send the control command to stop it. This isn't a problem, but we will want to stop it sooner than later. We will cover this in the next section.

To avoid unexpectedly turning on the spindle motor when powering on the machine, wait to flip the power switch to the on position until after EMC2 is running. This will ensure that the parallel port is in the appropriate state according to the configuration file to keep all motors off by default.

Starting Mach3

This can be done by using the icon on the desktop.

Spindle control and Emergency Stop

If the tooling is clear of all obstacles, you can press F5 to toggle the spindle motor on and off.

The switch on the right side of the mill, near the top will cut power to the spindle. This is the best way to shut it down in an emergency... but note that the axis can still move after the switch is thrown. Pressing Reset in the interface will signal Mach3 to make an Emergency Stop. You'll see the Reset button blink, and the status line at the bottom will read "E-Stop Triggered, press reset...".

Making our first motions

Jog Controls

To start, we're going to use the "jog" functions to move the milling cutter around and get a feel for what is "positive" and "negative" on the X, Y, & Z axis.

Especially, when starting out, limit motion to the X and Y axis as this has the least potential for damaging our tooling (aka, breaking a bit). As you get a feel for what's positive and negative, we will start using larger motions.

To start, hit the "tab" key to bring up the Jog controls. The main settings on this panel are the Jog mode, which can be either continuous or step. In continuous mode, holding down the motion keys (described below) will make the axis move continuously, and quite a lot. In step mode, pressing or holding the motion keys will move only a fixed step per key-press. The step distance is also configurable on the Jog control screen. You can hide the jog controls when not in use by pressing the Tab key.

To start, select continuous mode in the jog controls and press the Left Arrow and Right Arrow. Notice that the mill table moves left and right. This is the X axis. Next, press the Up arrow and Down Arrow keys briefly, notice that the mill table moves front to back. This is the Y axis. Finally, press the Page Up and Page Down keys briefly; notice that the spindle moves up and down. This is the Z axis. As you were moving the milling cutter around, you'll notice that the coordinates are displayed in the main window. This is where you can quickly survey where your tooling is located.

Obligatory Setup

Sometimes the Reset button in Mach3 will be flashing. This usually means that you exceeded the movement limits or speed of the mill and the controller has signaled Mach3 to stop. Often clicking reset is enough to clear this error.

Mill Controller Crash

Sometimes the controller will crash, this is usually evidenced by Reset complaining that it cannot clear a limit. It will offer a button that says "Fix this for me". "Fix this for me" actually redefines what an error is in the software (e.g. if input low is defined as an error, then it will redifine error as input high). Instead of clicking Fix this, you should try turning off and on the mill controller using the switch on the rear, lower-right side. Clicking Reset again should clear the trouble.

Advanced Manual Control - MDI (Manual Data Input)

Click on the MDI tab in the main Mach3 screen to the MDI Controls section. Within this section (the line next to input) we can type in actual G Code to move our tooling around. To start, we're going to use simple "go to" commands. This will rapidly move the tool to the position that we tell it to. Note, at any time, we can stop the execution of these commands by hitting the "stop" button on the screen or typing ALT-S on the keyboard. The first command we will use is "rapid go to" or "g0". As an example: make sure the tooling is well clear of the table using the jog controls and all axis are (roughly) centered. Reset all axis (X, Y, Z) to zero using the Zero Axis button located to the left of the current axis location. As you click zero axis, you should see the axis change to -0.0000.

To make our first motion, let's move the X axis to position 0.5. To do this, enter this command into the box marked Input: 

 g0 x0.5

The X axis should begin moving and it should stop 0.5" to the right of it's initial position.

Additionally, we can give multiple coordinates at once. Now try the command: 

 g0 x0 y0

This should send our tool back to the starting position. This can make things go much, much faster for resetting back to the position that you started with the mill at.

To have more fine grained control we can use the command "g1". There is nothing that G0 does which G1 cannot. The only difference in syntax is that we specify the feed rate of the motion as the first option. By default the mill is set to operate in inches per minute. Thus, unless you change this (via g code) it should be assumed that this will be the unit of measure for your commands.

Lets slowly raise our Z axis up one inch: 

 g1 f2 z1

Note, since we were at a position approx 1 inch up and told the mill to return to zero at a rate of F2 or 2 inches per minute, it will take approximately 30 seconds for this command to complete. Slow movement of the tool (especially when 'plunging' the z axis is a good idea as it allows for time to hit the "esc" key if things start going horribly wrong).

Now, let's build on some of these together: 

 g1 f10 x1 y1 z1

Whoops, back to zero: 

 g1 f5 x0 y0 z0

When moving back to zero you will see that the mill is moving half of the original speed (5 inches per minute rather than 10 inches per minute).

Let's really open this thing up and see what it can do. While watching this command move notice the feed rate indicator in the preview MDI tab. This will allow you to see the actual speed of the tool. 

 g1 f50 x1 y1 z1

Linear motion is great and all, but how about we dwell outside the euclidean space for a minute. The next commands that we are going to learn are G2/G3. G2 will make a clockwise arc while G3 will make a counterclockwise arc. The command syntax is as follows: 

*G2 - Command
*Fx - Feedrate at X inches per minute
*Xv - Destination X coordinate (in this case end at v)
*Yw - Destination Y coordinate (in this case end at w)
*Ix - X axis center point offset
*Jy - Y axis center point offset
*Za - Interpolated Z axis coordinate (optional)

To start, lets make a circle: 

 g2 f5 x1 y0 i-0.5 j0

Annnnd we fail. This is because we've given junk data to the mill. Lets try that again making a circle. Of course, to make a circle, we will want our beginning (1,1,1) to be the same as our destination (1,1,1) only changing the X axis center point offset. 

 g2 f5 x1 y1 i-0.5 j0

Fun math bits... run that command again and note the "distance to go" or "DTG" in the preview area. Note the distance at the immediate start of plotting our 1 inch diameter circle (2 * 0.5 X offset). This should be a predictable result

Tool Changing

Use a wrench to gently remove the chuck. Check the toolbox beneath the mill for different bits and other things as required.

Little force should be required to tighten the chuck; it has been said that finger-tight is often sufficient.

When you're done

Please cleanup the mill area and place tooling back into the mill toolbox under the bench.

Finally, turn off all three power switches noted above.

Thanks

Caution

Please avoid doing these things, unless you can deal with the consequences yourself.

  • Don't run the mill too far off axis. The stepper motors will usually make a harsh grinding sound when this happens.
  • Don't leave the mill completely unattended. Be prepared to hit the Reset key within at most a minute of hearing something go wrong.
  • Obviously, don't put your hands in hazardous places.

Otherwise, the mill is robust and newbie friendly.

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