Pm-940m-cnc (pre-assembled)

[B2]

Hi Sal,
Will do. I run 64 bit win7 enterprise and have only historic and limited experience with Linix.

This is the first project I did on FREECAD and one of the first cuts I made on my PM 940M. I generated the CAD on FREECAD, used FREECAD to generate a tool path and then simulated it to see the results, then I again used FREECAD to generate the G-code. I will upload it as a .txt file which it is.

I did not really know what I was doing and so it took me a long time to get it done. It was a heart shaped cut in a piece of brass for my wife. (I need to show her that the mill could be usefull!!!)

If I recall block size was 40x40x2mm and the cut was made from a small engraving tool.

I am assuming that you have an .xml configuration file that is working now. If not take the one that I uploaded earlier, change the extension from .doc to .xml and drop it in the Mach3 folder. It should work. I realized that maybe you are not running the Mach3 from its little start up program which gives you a choice of which configuration profile you want to install as Mach3 is booting. It allows you to copy, delete, and I think rename profiles. If not you may want to use this.

My suggested steps (maybe to detailed).

1. Take the tooling out of the mill.... for now.
2. Start Mach3 with a known profile.
3. After Mach3 is running, turn on the Mill power and hit the start button.
4. Control Tab to show the pendant and make sure its light is active.
5. Use the pendant, the manual commands, or even the manual cranks to move the spindle position to the middle of the x and y position and raise the z a few inches above the table, vise, etc.
6. In Mach set the the x, y, and z positions readings to zero. (i.e. put your software origin in the middle of the stages)
7. load the Gcode file
8. In the tool path side window you should now see a square with the trace of a heart more or less filling the square.
9. Click on a line of the G code to active the windown and then with the up and down keys you can see the path of the part lighting up as you click up and down line by line.
10. The code is written in metric mm and so once the Gcode is loaded so are the readings in Mach3. X, Y, X are shown in mm not inches. Prior to loading the g-code the profile was in inches and so if your xyz positions are not initially zero the Gcode box and heart in the tool path screen will be way off in the corner of the screen some where and all you will see is the initial move.
11. If everything looks right, start the cycle.

What the code does is assumes the origin (center of the brass block I was working on) is where the mill head is initially setting. Upon start up it loads settings, starts the spindle, then raises the tool, and moves off to near the top right corner of the block, lowers the tool into the work a little (0.1mm) and starts cutting the heart line. It uses arcs and straight lines. While this seems simple, it took me a while to figure out where to put the arc center and start and stop points including the tool offset etc.

Let me know.

Dave

PS. I have written a number of other G-code, but if I can avoid doing a CAD first I try to. That is the reason I like using the little Wizards built into Mach3. I steal this gcode from the wizard and then modify it to do my simple parts.

PS. If you open this gcode .txt file in Notepad it may be difficult to view as it seems to word wrap. However if you open it in in Notepad++ or even MS WORD you can view it just fine, line by line. Or, if you just load it into Mach3 you will be able to see it line by line. I am not for sure what is going on with Notepad.

 

[B2]

Hi Sal,

I got to thinking you might also want the FreeCad drawning, path gen, and the simulation file. Attached. However, once again the Hobby-machinist forum will not allow me to upload a file with a .FCStd extension. So I have changed it to .123 and you can change it back to .FCStd and open it with FreeCad

 

[B2]

Hi Sal,

I could not get the .123 extension to send either, but then got it to attach using the dummy extension... .doc. Anyway, you have to change it back to .FCStd to get FreeCad to accept the file.

If you have not figured it out yet, there are three tool paths in the FreeCad file, but I only used the first one to generate the Gcode I sent. If you want all three then you have to generate them separately in the FreeCad path generator and then either run them separately or manually put them together into a single larger file. The other two paths generate the letter "G" and the third makes a small square hole for a chain or string to go through. When made each of the tool paths cut all the way through the material. The heart drops out of the block and it has the letter and hole cut in it.

I am sure this could have all been done better, but this was my first FreeCad project.

I know that you ask for a small Gcode and I sent a large one, but I never made a small one in FreeCad and so would have to start from scratch. If you still want a small set of code I will see if I can generate one for you using the Mach3 Wizard. How about a something like just an arc, or a ring of drilled holes, or a slot?

It is getting late. I will try to get you one of those in the morning.

Dave

 

[B2]

Good Morning Sal,

Per your request a couple of short Gcode programs attached.

1) "cholepattern5-22_5 J101.txt" This drills 5 holes along a circle path separated by 60 degrees starting at a phase angle of 22.5 degrees from the horizontal. The circle radius is about an inch and it uses G73 drilling as I was working with plastic. I ran this program using my Mach3. So it should work.

2) "CutArcPressGaCover J121.txt" Simply cuts moves in x to approach a point an arc start point, then moves through a semicircle arc (180 degrees) about 1 in in radius and then returns to the origin and drops down for more cuts. I used this this to cut away a portion of a PVC tee pipe. So it should work in Mach3.

3) "ArcCutpocket - Copy.txt" This uses a spiral cut to make a pocket hole and repeats the cut 4 times at incremental 1/4 inch cut depths. I think it is about 1 inch in radius. I did not run this but it seemed to simulated fine.

Good luck.

Dave

 

[B2]

Hi Sal,

I have not heard from you for a while. Hope your efforts are paying off...?

Recently, I have been using FreeCAD to design some involute gears to convert my old South Bend 10 to make metric threads pitches and in reviewing the G-code Post Processors, I seem to get the best code generated with I use the "dynapath" Post Processor. It seems several of the other available post processors yield code that almost works, but commonly an incorrect feed rate. I think the G-code that I posted for the heart cut was generated using the "grbl" post processor, but I may have edited the Gcode to correct the feed rates ... as what I put into the tool profile does not show up in the G-codes generated by the post processor. However, dynapath, seems to work. Sometimes there is no feed rate entered, but other times there is an unreasonably high value which always seems to be the same (a default setting?). Below is the info on my version of FreeCAD and how I am running it. I picked this up off the Help About page of FreeCAD.

OS: Windows 7
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.13522 (Git)
Build type: Release
Branch: releases/FreeCAD-0-17
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: English/UnitedStates (en_US)

Since there is no specific FreeCAD post processor installed specifically to generate Gcode for our Mill/Mach3 (nor for Acorn) I guess I am lucky these work as well as they do.

Dave

 

[Sal_the_man]

Sorry for my late response @B2, I was out of the office for a few days due to an emergency. I've got time today to give your codes a shot. Thanks for the abundant help, @chocadile and I really appreciate it

 

[Sal_the_man]

@B2 your g-codes are working perfectly. So our post processor is the culprit

 

[Sal_the_man]

Our spindle for some reason has stopped working. I'm inclined to believe this is our problem. However, whenever I put in a velocity value it does not register my input and automatically goes to "0"

Thoughts?

 

[B2]

Hi Sal,
I really do not have any ideas other than bad wires. But I did check my machine out and here is what I found.

While my spindle motor movement profile is different from your photo, but it does not seem to matter what the settings are.... the spindle still works when I issue the M3 S### command or if I hit the spindle on and off button on the spindle window in Mach3. In fact, if you use the M3 S0 the spindle turns at very low rpm. M5 to stop the spindle. I even went so far as to set all of the settings in the spindle movement profile to zeros and the spindle still seemed to work fine with the manual commands. Initially, my spindle motor movement profile was:

(interchanged from yours)
Steps per : 1
Velocity: 120
other settings are the same as you show in your photo. However, in the graph there is a straight sloped line starting at 0,0 and going up to the top right corner 0.5 sec, 120 inches per minute, indicating that the velocity was always increasing and would reach the max setting at 1/2 second. Of course the units of this screen are all nonsense.... what does velocity mean for a rotating spindle? It should be in RPM or something. The software engineer cheated here and used the same screen as for the other axes! Poor! In fact, I think this entire screen maybe a in active. There must be somewhere else in the software/code that actually controls the spindle max RPM?

It would seem that with zero velocity that the spindle would not turn, but it did not seem to care on my machine. In fact, as I stated above, I set every entry on this screen to zero and hit the Spindle: Save Axis Settings so that all the readings would be zero, and my spindle could still be programed to run. So, these settings seemed to have nothing to do with the spindle turning. However, I should also tell you that once I had set all entries to zero I could not put the velocity value back! I would type in other values but the screen always put it back to zero. It always read zero and I tried a lot of things to get it to some other value! Since yours is reading zero already, you may not be able to change it to a non-zero value in/from this screen. So I restored my profile from one of the back up folders.

If you have not discovered the location of these, there under the sub folder: Mach3/XMLbackups or something like this. There should be a bunch of them as it seems to save a back up every so often. Likewise you seem to need a folder in the Mach3/macros sub-folder which has the same name as the profile and contains a hole bunch of little program setting files. If you look in the macro folder you should also see a folder name Mach3Mill. I think it was the folder first created when I installed Mach3. (By the way, I found that if I just double clicked on the .xml file that Windows explorer would open and show the contents of the file in line by line format. So at least you can read it even if it does not mean anything to you. I suspect that if one does a file compare between a profile that is working and one that is not working we might be able to decipher which line changes as configuration settings are changed.

So grab one of your backup .xml files, copy it to the main Mach3 folder, and change its extension from what ever the backup nomenclature is (example .xb3 etc) to .xml. Then make sure that there is a folder in your Mach3/macros folder with the same name and which contains all of the little files that the Mach3Mill folder contains. Start the Mach3 loader and choose the new profile (the one you just created from the back up profile .xml). After the Mach3 launches see if the spindle motor settings are restored to some other value than you show in your photo. It may not enable your spindle to work, but at least you will know it is not in the software.

Motor not running: bad connections? bad VFD? bad motor? Hidden interlock? I think I read that the VFD simply wants to see a DC input voltage between 0-10v to go from 0 to ~400 Hz to drive the motor. So in concept you could disconnect the wiring and connect a 1.5volt battery to the inputs to start the spindle turning. Anyway, you can look up the specs/manual on the VFD.

Good luck.

Dave L.

 

[Sal_the_man]

Hi Sal,
I really do not have any ideas other than bad wires. But I did check my machine out and here is what I found.

While my spindle motor movement profile is different from your photo, but it does not seem to matter what the settings are.... the spindle still works when I issue the M3 S### command or if I hit the spindle on and off button on the spindle window in Mach3. In fact, if you use the M3 S0 the spindle turns at very low rpm. M5 to stop the spindle. I even went so far as to set all of the settings in the spindle movement profile to zeros and the spindle still seemed to work fine with the manual commands. Initially, my spindle motor movement profile was:

(interchanged from yours)
Steps per : 1
Velocity: 120
other settings are the same as you show in your photo. However, in the graph there is a straight sloped line starting at 0,0 and going up to the top right corner 0.5 sec, 120 inches per minute, indicating that the velocity was always increasing and would reach the max setting at 1/2 second. Of course the units of this screen are all nonsense.... what does velocity mean for a rotating spindle? It should be in RPM or something. The software engineer cheated here and used the same screen as for the other axes! Poor! In fact, I think this entire screen maybe a in active. There must be somewhere else in the software/code that actually controls the spindle max RPM?

It would seem that with zero velocity that the spindle would not turn, but it did not seem to care on my machine. In fact, as I stated above, I set every entry on this screen to zero and hit the Spindle: Save Axis Settings so that all the readings would be zero, and my spindle could still be programed to run. So, these settings seemed to have nothing to do with the spindle turning. However, I should also tell you that once I had set all entries to zero I could not put the velocity value back! I would type in other values but the screen always put it back to zero. It always read zero and I tried a lot of things to get it to some other value! Since yours is reading zero already, you may not be able to change it to a non-zero value in/from this screen. So I restored my profile from one of the back up folders.

If you have not discovered the location of these, there under the sub folder: Mach3/XMLbackups or something like this. There should be a bunch of them as it seems to save a back up every so often. Likewise you seem to need a folder in the Mach3/macros sub-folder which has the same name as the profile and contains a hole bunch of little program setting files. If you look in the macro folder you should also see a folder name Mach3Mill. I think it was the folder first created when I installed Mach3. (By the way, I found that if I just double clicked on the .xml file that Windows explorer would open and show the contents of the file in line by line format. So at least you can read it even if it does not mean anything to you. I suspect that if one does a file compare between a profile that is working and one that is not working we might be able to decipher which line changes as configuration settings are changed.

So grab one of your backup .xml files, copy it to the main Mach3 folder, and change its extension from what ever the backup nomenclature is (example .xb3 etc) to .xml. Then make sure that there is a folder in your Mach3/macros folder with the same name and which contains all of the little files that the Mach3Mill folder contains. Start the Mach3 loader and choose the new profile (the one you just created from the back up profile .xml). After the Mach3 launches see if the spindle motor settings are restored to some other value than you show in your photo. It may not enable your spindle to work, but at least you will know it is not in the software.

Motor not running: bad connections? bad VFD? bad motor? Hidden interlock? I think I read that the VFD simply wants to see a DC input voltage between 0-10v to go from 0 to ~400 Hz to drive the motor. So in concept you could disconnect the wiring and connect a 1.5volt battery to the inputs to start the spindle turning. Anyway, you can look up the specs/manual on the VFD.

Good luck.

Dave L.

Thanks B2. Gonna give your advice a shot. I had our VFD working briefly but it was flashing the "-LU-" code prior to shutting down. So it very well may be a hardware issue.

Going to back up one of the files anyway