[bhurts]

Tom
You are the man. You have the best customer support I have received from anyone. I tried a different k-flop and got the same results. I then reread your last post and and comments about maybe being ground/noise. On a hunch I removed the wire I mentioned above going from the k-flop pc supply case to star ground. Its been there since the beginning and I have cut so much stuff with no issues it never occurred to me it might be part of my issues. And the results are in. No more encoder spikes on any axis under any conditions so far. Also all motors are quieter and encoders seem to be dithering less. They are drawing less current as well wile running and on plots. I will now have to retune all my motors since I think the noise was limiting how much gain I could add before overcurrenting. Since there all three already very stable ill just go through the step and see how far I can push them. I told you I thought the problem was me.

Thank you for all your help
Ben

[bhurts]

And a quick update on retuning. I have started with y since its been all the trouble. Before removing the wire and with the spiking in order to be anywhere near stable P=1 I=.0001 and D=4. On a 30000 count move over 1.5 seconds following error was best case 35-50counts. Now its at P=9 I=.0001 and D=60. On the same 30000 count 1.5 second move max following error is 5-9 counts. On a 5000 count 1 second move its only 4-5 counts. I haven't even tried to push things so it can be better I'm sure. I can't wait to see what happens when I redo x and z. I can't say thank you enough.

Ben

[TomKerekes]

Hi Ben,

Great news. Sounds like there was some ground loop causing earth ground currents to flow through SnapAmp/KFLOP DC ground. Thanks for your perseverance.

Regards

[bhurts]

Ok on to the next question. I would like to control my vfd from k-flop. I'm thinking +- 10v would bebest. The vfd is a hitachi wj200. I will need a way to get the +- 10v signal from k-flop. I see that cnc4pc sells converter borads for this purpose. They have two that look like they should work. One converts pwm to the analog signal and the other converts step direction to analog. The step direction board is a little cheaper. Which one would you recommend for best performance?

Thanks
Ben

[TomKerekes]

Hi Ben,

I think Step/Dir will provide more resolution and be easier for you to configure. The Spindle then becomes like a Step/Dir Axis that can be controlled by issuing Jogs to the Axis. See here for a description on how to do this.

Although I think those devices generate a 0-10V signal rather than +/-10V signals. They expect the VFD to require switch contacts (relays or optos) to change direction.

Regards

[bhurts]

Thanks Tom. Your correct its 0-10v. I will never run in reverse so I shouldn't need the relays but they do come on the board.

Ben

[bhurts]

Ok I ordered the 0-10v board. Ill get back to that when the board arrives if I have any issues. The next thing I'm wondering is if there is a pendant you can recommend for use? Hopefully something that has already been used by others and will not be to difficult to setup. I will say if you ever offer a pendant of your own that is preset for k-flop I would be on board 100%. I don't figure its in the cards but thought I would mention it. I know there are Bluetooth and WiFi jogging apps for android phones. Do you think something like that could be made to work? I really don't need anything special from a pendant. Something like the jog section of k-motion cnc with the ability to pick step sizes and buttons for zeroing the current fixture offsets x,y and z. I just need to find the part zeroes and z zeroes and set them.

Thank you
Ben

[TomKerekes]

Hi Ben,

Pendants/MPGs are difficult because everybody has a different idea of what the functionality should be.

You can use a Gampad with KMotionCNC either wired or wireless. Anything like this connected to the PC/USB/Windows will not be 100% real time and jsut some basic buttons are supported. See Description:




We recommend a hardwired mpg connected directly to KFLOP like this:

Attachment 218886

Keling sells them here.

Attached is a wiring diagram a User Submitted with it wired to KFLOP JP6.

There are example C files such as MPGSmooth.c to monitor it.

HTH Regards

[bhurts]

I received my spindle control board the other day. I have a few questions about setting it up. I do not need to ever reverse the router. I'm thinking I don't need the direction pin at all. I believe I just need to hook the step output and a ground pin from k-flop to the corresponding terminals on the board? I should then setup a new axis (say axis six) on the step response screen to use that pin. I'm not sure what settings to use for the axis or how to get it to ramp the spindle up and down over 10 seconds or so. I saw the spindle using jogs c program. Since I am not going to be reversing the motor I'm not sure how m3 will come into play. I'm thinking something like this. M3 will enable the spindle axis. Sxxxx will give the speed required and get it moving. Last m5 would ramp the spindle to stop and then disable the axis until m3 is called again. This would insure safety during tool changes. Also I'm not sure how to setup k-motion cnc to do this. Do I need 3 active c-code files to do this? The last thing is at the end of my snapamp enable c I run my definecoordsystem (0,1,2,-1) would this need to change? Am I trying to do this all wrong. Any help or guidance would be appreciated.

Thanks
Ben

[TomKerekes]

Hi Ben,

I do not need to ever reverse the router. I'm thinking I don't need the direction pin at all. I believe I just need to hook the step output and a ground pin from k-flop to the corresponding terminals on the board?

I think that is correct. If you don't connect the direction to the board then I think you should ground the input to the board and not leave it floating.

I should then setup a new axis (say axis six) on the step response screen to use that pin. I'm not sure what settings to use for the axis or how to get it to ramp the spindle up and down over 10 seconds or so.

Correct set up an Axis as a Step/Dir Axis. I think I read that at 50K Steps/sec the board would put out the full 10V. So to ramp from 0 to 50,000 steps/sec in 10 seconds would be an acceleration of 5,000 steps/sec^2. Set Jerk to a huge value like 1,000,000 so the acceleration begins immediately.

Since I am not going to be reversing the motor I'm not sure how m3 will come into play. I'm thinking something like this. M3 will enable the spindle axis. Sxxxx will give the speed required and get it moving. Last m5 would ramp the spindle to stop and then disable the axis until m3 is called again. This would insure safety during tool changes. Also I'm not sure how to setup k-motion cnc to do this. Do I need 3 active c-code files to do this?

Yes I think that is correct. Everything will work just like a system that reverses except M4 will never be commanded. M3 is for ON forward and M5 is for Stop spindle. S sets the desired speed. We recently added a page about this here.

The last thing is at the end of my snapamp enable c I run my definecoordsystem (0,1,2,-1) would this need to change?

No. The Spindle axis is not part of the coordinated motion system.

HTH
Regards

[bhurts]

Ok I have wired from the board to the vfd and from the board to a powersupply. I wired the boards step input to k-flop jp7 step0 pin 15, direction input to direction0 pin 16, and ground to pin 26. On the configuration screen I selected no input and step dir output. For output channels do I select channel 0? Also do I need to change anything else on the configuration screen? On the step response screen I put 50000 for velocity, 5000 for acceleration and 1000000 for jerk. Do I need anything for pid values or anything else?

In k-motion cnc under the tool setup screen I believe I need to select a action for m3, m5, and s. I read the link you provided but am still unsure how to proceed. I believe I need to select execute program for each one. I'm not sure which programs under the spindle using jogs folder to select for each. Also I'm not sure what changes to the programs to make. Can the same thread be selected for all 3 programs? What variables do I choose? I hooked up the direction pin so it wouldn't be floating but I am not actually using that pin. Since I am just commanding speed can I just set thing up so sxxxx runs and s0 stops?
Last my spindle is 18000 rpm at 300hz. How do I get things to show the correct speed? I hope I'm not asking to many questions but I learn things like this slowly. Once I have successfully gotten everything going and see how each thing works I should be able to do it again without help.

Thanks
Ben

[TomKerekes]

Hi Ben,

I wired the boards step input to k-flop jp7 step0 pin 15, direction input to direction0 pin 16, and ground to pin 26. On the configuration screen I selected no input and step dir output. On the configuration screen I selected no input and step dir output.

good

For output channels do I select channel 0?

No. Add 8 to switch to TTL Output mode which I think that board requires.

Also do I need to change anything else on the configuration screen?

no

On the step response screen I put 50000 for velocity, 5000 for acceleration and 1000000 for jerk.

good

Do I need anything for pid values or anything else?

no. There is no feedback

In k-motion cnc under the tool setup screen I believe I need to select a action for m3, m5, and s. I believe I need to select execute program for each one.

Correct. But before you do anything in KMotionCNC first test that you can control Spindle from KMotion.exe. Move on the Step Response Screen. And command Jogs on the Console Screen.

Then in KMotionCNC Tool Setup configure the Programs in C:\KMotion431r\C Programs\SpindleUsingJogs\CSS

All the programs in that directory include the file MySpindleDefs.h (shown below) modify it for your situation. Set the Spindle Axis to the axis you are using for your spindle. You will need to compute the Factor for your system. Set the CW and CCW bit to some dummy bits.

#define SPINDLEAXIS 6        // Axis Channel to Jog to rotate Spindle
#define FACTOR (1000/60.0)   // to convert RPM to counts/sec (counts/rev / 60.0sec)
#define SPINDLECW_BIT 154    // bit to activate to cause CW rotation
#define SPINDLECCW_BIT 155   // bit to activate to cause CCW rotation
#define SPEEDVAR 99          // global persistant variable to store latest speed
#define STATEVAR 98          // global persistant variable to store latest state (-1=CCW,0=off,1=CW)
#define KMVAR PC_COMM_CSS_S  // variable KMotionCNC will pass speed parameter (113)

Can the same thread be selected for all 3 programs?

Yes because they wont run at the same time (but a different Thread than your Init)

What variables do I choose?

M3,M4,M5 don't pass any information set the Var to 0
S must pass the Speed in Var 113 (as KMVAR above is set at)

Since I am just commanding speed can I just set thing up so sxxxx runs and s0 stops?

I suppose that could be possible but somewhat non-standard. Lets use M3 and M5 to turn the spindle on and off. The C programs are already set up to do this.

How do I get things to show the correct speed?

By adjusting the FACTOR in the MySpindleDefs.h file. After you get the Spindle running command the axis to Jog at various speeds (in counts/sec). For each speed check the RPM. This will allow you to compute the FACTOR.

HTH
Regards

[bhurts]

Thank you very much that makes it easier to understand. The only question I have left is about adding 8 to the output channel. Do you mean select output 7? My snapamp uses 8 9 10 and 11. Does this not apply when using just k-flop? This question will also apply to the setup I am helping a friend with.

Thank you
Ben

[TomKerekes]

Hi Ben,

The only question I have left is about adding 8 to the output channel. Do you mean select output 7? My snapamp uses 8 9 10 and 11

No. Specify the number 8. SnapAmp PWM Bridge OutputChan #8 and KFLOP Step/Dir Generator OutputChan #8 are two entirely different things.

HTH
Regards

[bhurts]

Ok here's a strange one. It has happened 2 days in a row at the same place position wise on the router. When issued a g53 G00 X0 Y0 Z0 from mdi when all axis are about .5 from home all motion stops the dro's go yellow and I get the read failed auto disconnect message. I always issue this command at the end of every session and it just started yesterday. After disconnect it is instantly back on but all dro's are now zero. I have to run the enable snapamp program and redownload each channel to get going again. I can then run just fine with no problems. Is there anything you can think of that might cause this? If not is there a process of elemenation you can suggest to try a work through it.

Thanks
Ben

[TomKerekes]

Hi Ben,

It sounds like KFLOP may be rebooting for some reason. Possibly a power supply issue, grounding issue, noise issue. I can't think of why it would occur at a particular xyz position. Or why it would have changed. The other possibility is a software bug. We have had issues with noise being picked up on KFLOP's reset line. Especially if long (ie more than a few inches) ribbon cables are connected to KFLOP connectors with reset (JP4, JP6, JP7). A solution is to add a filter cap on Reset near KFLOP. I'd suggest trying that. This may help with ground or supply noise also. See this topic on the Yahoo Group.

Regards

[bhurts]

I would like to know how rounding off numbers works in k-motion cnc. I sometimes get errors when running simulation stating endpoint of arc cannot be reached. My cam program has a maximum toolpath tolerance of 0.00005. Also when setting fixture offsets and tool offsets for the machine I often get 6-7 decimal places inserted for saved values. I only need 4 decimal places max saved for these values. Is there a way to setup toolpath rounding?

Thank you
Ben

[bhurts]

I must add that the cam program only posts 4 decimal places. Also when I get the arc endpoint error I just have to add .0001 to the r value and that allows things to run fine.

Ben

[TomKerekes]

Hi Ben,

We have these tolerances

/* numerical constants */
#define TOLERANCE_INCH 0.0005
#define TOLERANCE_MM 0.005

If your CAD is outputting 4 digits that should not be a problem. Could you post a code fragment that causes a problem?


Regarding rounding: not everyone might agree to 4 digits. A few roundoffs to tenths could accumulate to almost a mil. Would 5 digits in Inches be acceptable?

Regards

[bhurts]

Hi Tom
I haven't gotten a chance to post the code you asked for yet. I will try to later when I get home to a real pc. In the mean time I finally got brave enough to hookup my home switches. I am having a issue with the homing routine. I am using the simple home 3 axis c program. I am hooked up to snapamp optos 0,1and2 and changed the c program to read bits 72,73 and74. It moves away from the limits and zeros without ever moving towards the switches. The bits are always checked on the io screen. When I put a peice of metal in front of the switches the bits uncheck. What should I change on the home program to make it read when the bit goes low instead of high?

Thanks
Ben