gcode resetting my surface zero to Z-0.200"

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Mr.Chips
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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

Yes I sure am very interested.
I am just out in the garage thinking where I want to make changes.
But before I tear it down I want to make some measurements on the Z assembly . Rotational force of the different pirces. And linear lift force with acme thread detached. Have to find the culprit. So far it’s not obvious or one of us would have found it. Well we have, everything been talked about.
This actually is my second machine. The first was a fixed gantry all MDF and gas pipe for rails. All acme screw. I chose a fixed gantry because of the rigidity.
The movable bed was heavy had th put a lot of supports under the gas pipe to keep it from sagging.
The only thing I made on it was the router mount.
Anyway I want to hear about your new machine.
Later
Hager

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Re: gcode resetting my surface zero to Z-0.200"

Post by wmgeorge »

Before this is closed out two quick questions 1 Where did the OEM motor tuning Acc and others come from? 2 If it’s indeed a tuning issue then give the guy some settings to use!!
Sorry been on a road trip the past few days, now have my lovely wife driving.

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Re: gcode resetting my surface zero to Z-0.200"

Post by GME »

wmgeorge wrote:Before this is closed out two quick questions 1 Where did the OEM motor tuning Acc and others come from? 2 If it’s indeed a tuning issue then give the guy some settings to use!!
Sorry been on a road trip the past few days, now have my lovely wife driving.
Bill,

The first question is a good one. As to the second question, it does not appear to be a tuning issue, i.e. a setting issue. As indicated in earlier posts, Hager got the things to work at an even lower acceleration that he had been using, but then things got bad again, even at the lower setting. Worse still, the cutting deep got worse, and the stepper started making growling noise as it lost steps. Really sounds like a binding issue in Z axis somewhere.

The acceleration for normal use seems way too low to me, but I don't know his machine and what it can take. I used an acme screw on my first machine, although mine was a five start, and his is only a one or two start (I don't remember which). I suspect the number of starts would make a difference, but I don't know enough about it to make an assessment or an intelligent recommendation. Anyway, with my five start screw, I ran my acceleration at 30 and it worked just fine.

Gary

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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

LOL,
Too many posts and easy to get things confused.

I lowered the acc and g
And ran this cut. It ran fine.

But when I changed back to the higher ACC and G’s and I ran a air cut I could hear it buzzing but it didn’t at the lower Acc

Here is a cut ran at the lower Acc
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115CDC02-D8AB-45AD-B6DF-E7136257A194.jpeg

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Re: gcode resetting my surface zero to Z-0.200"

Post by GME »

Hager,

I just thought of another test that may be worth trying. It may allow you to more definitively isolate the problem to either binding somewhere, or back to looking at the power supply and drive. Shouldn't be too much trouble, since you plan to tear Z down anyway. Here are the steps (pun intended):

1. Increase your acceleration to 30 for the Z axis.

2. Remove your Z axis stepper and put it on your router table.

3. Load your Chinese character file and run it.

Your stepper was buzzing at the higher acceleration, but still pretty low. Since the stepper is disconnected and there is nothing to constrain it, there should be no issue with an acceleration of 30, assuming the electronics are okay. See if it buzzes. I believe we have been interpreting the buzzing as the sound of lost steps. If it buzzes with the acceleration set to 30, but disconnected from the axis, I would tend to rule out binding in the Z axis. That puts you back to looking at the power supply and drive. If it doesn't buzz, then you are back to looking at the coupling, flange bearing and Linear rails. Either way, this test may put you closer to the answer.

Gary

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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

That’s an excellent idea, I’ll do that when I finishing my round of testing.

Testing and the higher, 10 year Acc settings

Testing amps directly at the X and Z drivers rather than all the drivers at 10 50 and 70 IPM
Then I’ll have the Z driver run the X stepper and X driver run the Z stepper.

Kinda want to find a week link.

Hager

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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

Completed testing of measuring amps directly from the individual drivers than a the reading taken of all drivers, hoping to pinpoint a trouble spot.

Ran three tests of the individual drivers at 10,50,and 75 IPM. The test were ran at the 10 year acc settings, (higher)
Ran one test at 50 IPM by plugging the X axis driver to the Z stepper, and the other way around.

Didn’t find anything that was outstanding.
I did nit hear and buzzing during the tests.

The buzzing seems to happen when there is a lot of XYZ movement. Thinking to run the file again and find the section where there is buzzing and stop the run and cut and paste the section of the file where it happens and make a file and paste the problem in several times and try different acc settings to see what it takes to prevent the lost steps. Anyway want to try your test first.

Here’s the data.
I’ll set the driver/stepper connections back to the standard way.
Attachments
79EF1F69-B4B2-429D-B6FE-9018899FB218.jpeg

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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

Set acc to 30
Removed the Z axis and put two leather gloves under it and electrical taped it solidly to the flat on top of the Z assembly
I moved the driver connections from the A driver back to the original Z driver
Set Z acc to 30.

Loaded the same file

And ran it for about a half hour. Didn’t hear any buzzing.

Frequently the Z would go to +0.200 at 5 IPM.
But a couple of lines after that at the end of the line there is a F35, and all movements XZ and Z are ran at 35 IPM. In the setup the Z movement is set to 5, I thought that meant all Z movements would do done at 5?

Photo showing the code that shows the F5 and then F35 and the end of a couple of lines down.

Photo of the Motor tuning.

Any ideas you want to try while it’s still running?

Thanks for all your suggestions and time spent.
Hager
Attachments
5B641FC6-1D98-4F81-B6D1-B58E351CCCB2.jpeg
A1D643AA-6CC2-4CCB-BAD7-7403F74B606C.jpeg

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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

Sent same file twice I’ll try again
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C73B5B84-2E20-4F09-AE45-AC15E3D8BFC7.jpeg

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Re: gcode resetting my surface zero to Z-0.200"

Post by GME »

Mr.Chips wrote:Set acc to 30
Removed the Z axis and put two leather gloves under it and electrical taped it solidly to the flat on top of the Z assembly
I moved the driver connections from the A driver back to the original Z driver
Set Z acc to 30.

Loaded the same file

And ran it for about a half hour. Didn’t hear any buzzing.

Frequently the Z would go to +0.200 at 5 IPM.
But a couple of lines after that at the end of the line there is a F35, and all movements XZ and Z are ran at 35 IPM. In the setup the Z movement is set to 5, I thought that meant all Z movements would do done at 5?

Photo showing the code that shows the F5 and then F35 and the end of a couple of lines down.

Photo of the Motor tuning.

Any ideas you want to try while it’s still running?

Thanks for all your suggestions and time spent.
Hager
Hager,

Sorry, but you lost me with your reference to "Z movement is set to 5." All of the motor settings for each axis have to do with movement. Note that you did not include a shot of your motor tuning. You uploaded the same screen shot twice and left the motor screen out.

The "F" code, e.g. F5 and F35 refer to feedrate in IPM or MMPM. I believe the feedrate in the G Code cut file is limited by the velocity set in your motor tuning, i.e., the machine will not travel faster than the IPM set in velocity. So, if your velocity is set to 100 and there's an F150 (150 IPM) call in your cut file, the machine will only travel at 100 IPM, the max setting in the motor tuning.

The only other test that comes to mind is the same test, but with increasing the velocity and leaving acceleration at 30. Increasing the velocity should work you power supply harder. The velocity for my acme screw was set at 200, which is faster than it will generally ever run in actual practice. Of course, your Chinese character file will not run anywhere that fast, because you have been using much slower speeds. I suggest you go back in the V-Carve file, change the feedrate for your router bit to 100 IPM and generate a new toolpath for test purposes. If 100 IPM is too fast for your X and Y axes, you may want to unplug the steppers and just run with Z alone.

Gary

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Re: gcode resetting my surface zero to Z-0.200"

Post by TReischl »

A bit of clarification is in order about how feed rates work when vcarving.

Start with the feed rates being set to the following: XY feed 30 IPM, Z feed set to 5 IPM.

When vcarving the only time the Z feed of 5 ipm is active is during a straight down plunge move.

The rest of the time when it is cutting on the horizontal plane or moving up a slope in a corner the programmed feed rate is 30 IPM. The machine will try to accelerate to that feed rate. Example:

N36 G00 X-5.4635 Y-2.3284
N37 G00 Z0.0200
N38 G1 X-5.4635 Y-2.3284 Z-0.3000 F5.0 (straight down plunge move at 5 IPM)
N39 G1 X-5.4369 Y-2.3550 Z-0.3000 F30.0 (All subsequent moves will be at 30 IPM)
N40 G1 X-5.4369 Y-2.3847 Z-0.2813
N41 G1 X-5.4369 Y-2.4182 Z-0.2625
N42 G1 X-5.4369 Y-2.4375 Z-0.2531
N43 G1 X-5.4369 Y-2.4597 Z-0.2438
N44 G1 X-5.4369 Y-2.4878 Z-0.2344
N45 G1 X-5.4369 Y-2.5073 Z-0.2297
N46 G1 X-5.4369 Y-2.5305 Z-0.2262
N47 G1 X-5.4369 Y-2.5534 Z-0.2250
N48 G1 X-5.4369 Y-3.5404 Z-0.2250
N49 G1 X-5.4369 Y-3.5634 Z-0.2262
N50 G1 X-5.4369 Y-3.5866 Z-0.2297
N51 G1 X-5.4369 Y-3.6060 Z-0.2344
N52 G1 X-5.4369 Y-3.6342 Z-0.2438
N53 G1 X-5.4369 Y-3.6564 Z-0.2531
N54 G1 X-5.4369 Y-3.6756 Z-0.2625
N55 G1 X-5.4369 Y-3.7092 Z-0.2813
N56 G1 X-5.4369 Y-3.7388 Z-0.3000
N57 G1 X-5.4961 Y-3.7904 Z-0.3000
N58 G1 X-5.5331 Y-3.7904 Z-0.2813
N59 G1 X-5.5633 Y-3.7904 Z-0.2688
N60 G1 X-5.5928 Y-3.7904 Z-0.2594
N61 G1 X-5.6223 Y-3.7904 Z-0.2531
N62 G1 X-5.6421 Y-3.7904 Z-0.2508
N63 G1 X-5.6619 Y-3.7904 Z-0.2500
N64 G1 X-6.3963 Y-3.7904 Z-0.2500
N65 G1 X-6.6463 Y-3.5404 Z0.0000
N66 G1 X-6.3963 Y-3.7904 Z-0.2500


In other words, during vcarving the controlling feed rate is NOT the Z axis feed rate. The control is not trying to blend the Z and XY feed rates, it has no way of doing that since there is only one F word register in the control software.
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Mr.Chips
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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

Unplug the steppers? Vaguely I recall something that would damage the drivers p, and I thought it was that if a driver didn’t have a load on it it would damage them. Or am I mistaken.
Just want to be sure this is OK to do before I get started.
Thanks

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Re: gcode resetting my surface zero to Z-0.200"

Post by ger21 »

In other words, during vcarving the controlling feed rate is NOT the Z axis feed rate.
Unless the Z axis is setup so slow that the X and Y axis are waiting for it.
Gerry - http://www.thecncwoodworker.com

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Re: gcode resetting my surface zero to Z-0.200"

Post by GME »

Mr.Chips wrote:Unplug the steppers? Vaguely I recall something that would damage the drivers p, and I thought it was that if a driver didn’t have a load on it it would damage them. Or am I mistaken.
Just want to be sure this is OK to do before I get started.
Thanks
I'm not sure about damaging the drives. I've not read anything on the subject, but better to play it safe.

Actually, it would be better if the X and Y steppers were running, because they would be drawing current. If there is a fault in the power supply, having all the steppers drawing current may be more likely to disclose it. Probably a PIA, but if you do not believe your machine can handle the speed, better to disconnect the steppers from the screws. IMO, the best outcome would be to run at the increased IPM with all steppers connected, since there would be some amount of load on them. At the end of the day, whether to leave connected or disconnect from the screws is a question of what your machine can safely handle.

Gary

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Re: gcode resetting my surface zero to Z-0.200"

Post by Mr.Chips »

Ok I’ll have all the steppers connected.
When I first started running this CNC I obviously was under some misconceptions in how it operated and they are becoming clear.
Namely i was under the impression that in EDIT TOOL when you set the FEED RATE and PLUNGE RATE that dictated the X,Y and Z IPM that would be used.
MOTOR TUNING: I didn’t get any suggested starting point or recommendations. Even Marcus of Gecko said he couldn’t give any recommendations because it all depends on your machine. I did not realize that the MOTOR TUNING overrode settings made in the EDIT TOOL section.
So, all these years I have again been fat, dumb, and happy running all this time being lucky. Until something got old, or worn and brought this to the forefront. I so apologize for this loooooong journey, it possibly could have been shortened had you all known all the details of my machine up front.

I have configured the file WOMENS 2019 Z 2.TXT as the below screens show.

Please take a look at the motor tuning and let me know the settings I should be using befor I start running the next test.
I’ll be loading 5 files don’t think I can attach them all to this file, so I’ll put three here and two on another post.
Attachments
ECCB5F18-BA43-49A4-B7D3-13EC80A1410B.jpeg
46A29151-EE2F-41E2-8F03-D797BC3B6B3D.jpeg
B393C87E-C971-4839-858D-4016024C4A26.jpeg

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