| EL34's CNC Stuff |
| Back to main CNC page |
Using the Probe function in Mach3 for Auto bit centering,
finding the Z surface and finding X-, X+, Y-, Y+ edges. |
| - |
|
I saw this post on CNC zone about auto
centering your bit and finding the edges of material. I have been wanting to do this for quite a while, and so I set out to set up a probe add these functions to my custom Mach3 screen. The CNC zone post link above has info on downloading and installing a Mach3 blue screen that already has all the buttons you need to do this Down below, I show how I added/copied the blue screen button functions to my custom Mach3 screen |
|
To edit your Mach3 screen, you will need a Mach3 screen editor. You can download a couple different ones for free at the Mach3 web site here. Scroll down the page until you see the Screens section. Screen4 is the standard Mach3 screen editor. It's sort of primitive, but it works. The Klaus Mach screen editor has some really cool features that I like. I used the Klaus editor and Scrren4 to edit my custom screen. |
| Click on the image to see a larger image |
 The way it works is that if pin 15 on my Probotix breakout board touches the common ground, then that is the Probe trigger. The Minus wire is connected to the common ground on my Probotix breakout board. The plus wire is connected to pin 15 on my Probotix breakout board. Each wire has an alligator clip on the business end. I clip the minus wire to my tool bit The plus wire is clipped to the metal work piece or some other piece of metal used to find an edge When the bit touches the metal work piece, pin 15 is grounded and that is the probe trigger Note that my tool is a Rotozip, which is a double insulated tool. That means that my spindle is insulated from the frame of my CNC machine and so I must also use a ground wire. If you have a spindle that is connected to the frame of your CNC, you can just use the Red wire. In that case, you would connect the common negative to the frame of your machine. Your tool bit would then be connected to the common ground and you don't need the ground wire clamped to your tool bit. |
| - |
 |
|
To set up a Probe in Mach3, you have to go to the Config menu, then pick ports and Pins, then the Input signals tab Scroll down the menu until you see the Probe line Enable the probe and then set the Pin number you are using (15 in my example above) Make a green check in the active low column. Don't forget to save your settings in the Config menu Now Mach3 is ready to read probe input on pin 15 |
| - |
| Click on the image to see a larger image |
 |
|
Here's a shot of my custom Mach3 screen. I created my Mach3 main screen to be very simple, no cluttered graphics and only items that I actually use all the time. I had to get rid of a few items on my custom screen that I was not using in order to make room for all the new buttons, LED's and Z+ entry field. The new items I added to my Mach3 custom screen are: Z surface Button The Z surface button is used to find the top surface of the material. The bit will slowly descend until it touches a metal surface and then it will stop. If your work piece is metal, you can go ahead and Zero out the Z axis at this point. If you use a metal plate to find the surface, the Zero Z point would actually be Z- plus the thickness of that metal plate. The green entry field below the Z surface button. After the surface is found, the bit will raise up the amount you enter in the green box. Four Axis buttons, X-, X+, Y-, Y+ Each one of these buttons will slowly move the bit until it touches a metal edge. You can then zero out that axis. If you use some other metal plate to find the edge, the thickness of that plate has to be taken into account. The four way arrow button The four way arrow button searches all four directions, Y+, Y-, X-, X+ and then goes to the center of what it finds. You can then Zero out the X and Y axis. This is the function I like best for many of the small round objects that I have to machine. Four Red LED's These led's light up when the bit touches a metal surface. |
| - |
| Click on the image to see a larger image |
 |
|
Here's an example of editing a button to run some VB script code. Note that I copied all the code from the Blue Screen example from the CNC zone post. See my link at the top of the page to the CNC zone post where you can download the Blue screen. I had to add my own buttons, LED's and graphics to my page first. My screen shot example above: Clicking on the Z down button displays all the properties of this button. Notice that the Execute code field has some text which is not quite all visible. This is the VB script code that will execute when the Z down button is pressed. Double clicking on the Execute code field opens up a text editor that displays the full script code. See the screen shot below of what the script editor screen looks like. I copied the code from the Blue screen buttons and added it to my buttons. I had two copies of the Screen editor running. One copy had the blue screen open and the other had my custom screen open. I just had to go back and forth between each screen editor to copy each button, led, etc function I wanted on my screen. You can set up all the buttons, LED's, etc by copying the properties from the Blue screen. If you are not familiar with the screen editors, I suggest you make a copy of one of your Mach3 screens and practice on it first. A screen file ends with .set and they can be found in your main Mach3 folder. |
| - |
| Click on the image to see a larger image |
 |
|
When you double click on the execute code field, it opens up the code in an editor screen like this one. This is the code for the Z axis down button. You can edit any of the code you like. If you close this window, a dialog box will pop up asking if you want to save the code to the screen. Say yes and then that code is now attached to the Button. |
| - |
|
I shot a couple movies of the bit centering in action on a couple different work pieces. First I press the Z down button to find the surface of my work piece. After it finds the surface I zero out the Z axis. I then raise the bit up just a bit so I can run the centering function without the bit dragging. I then press the 4 way arrow button in the middle of all the axis buttons. The tool bit searches in all four directions until it touches metal. After it finds all four edges, it goes back to the exact center and stops. You can then zero out all 4 axis. Now all four axis and the Z height are zeroed and ready for action. Note: You can play these movies on YouTube or download them here. If you click on the Windows media movie, it should do some buffering and then play in Windows media player Windows media movie #2 YouTube link to movie above Windows media movie #1 YouTube link to movie above |
| - |
Enter My Tube Amp Parts Store Here
Mobile users Enter My Tube Amp Parts Store Here
The Tube amp Library of information
Click the link above for Tube amp info, Schematics, Board building information, Projects, Mods, Transformer diagrams, Photo's, Sound clips.
There are hundreds of pages of Tube amp information on my library page.
Please visit my Tube Amplifier Forum
Here's the place you can go to ask tube amplifier questions.
You will find a large community of friendly amp builders at the link above.
Check the huge library of Schematics here
Design your own custom Turret Board or Eyelet board
DIY Layout Creator file analyzer program
DIY Layout Creator file library
How to email me
|
MEMBER OF PROJECT HONEY POT Spam Harvester Protection Network provided by Unspam |