Z axis motor stops with grinding sound, loses position

[ncsak]

Moving the spindle up or down with the Z+/Z- button sometimes results in the spindle stopping with a grinding/squealing sound. Also can fail
after bit touches puck and moves up for clearance. Sometimes it will fail after a job completes and the spindle raises to a stop position. It 
seems to work if I move (Z+/Z-) in small increments of 1" or so. After making this sound and stopping the remaining travel distances are lost.

I powered the machine (AR6Pro) off and manually turned the Z axis lead screw fully down and up. There is no binding in either direction.
This seems to happen more often in the mornings but not always. Overnight shop temps. are in the mid to upper 50s (~55F this AM). 
The X and Y positions are not affected and don't have this problem. I can move the spindle to the bottom of its travel range, then use the 
ZRN/Home Z Axis to bring the spindle to the top of its range and the problem does not occur. I wiped the Z screw, lubed and ran it through
its full range.

It seems that the up/down speed (Z+/Z-) is too fast for the motor and it stalls. Don't know if it's stalling or sensing an overload.

Is there a parameter that I change to slow down the up/down speed when I use the Z+/Z- buttons. 
Thought I would post here before contacting Axiom.

[zucaticorp]

I'm having what I think may be the same problem.
Just started this afternoon.
Nothing changed with the machine bu the Z-Zero puck no longer works as it did before.

[jwardy]

I'm having similar issues. I tried speeding up the Fast Speed and that seemed to be what caused it - I am now back to 2500 and may go lower to 2000. I found this under Menu, Auto Pro Setup, Work Speed. Try selecting your Fast Speed from this menu option, delete the existing value (also note what it is) and replace it with a lower value. Another possible source of issue for me is that I tried to use the Home Position in Vcarve (material setup) to tell the spindle to move out of the way when done with a job. For some reason, it can't handle that. I'm going to try and go back to a 0,0 home position and I'll try changing the stop state instead. BTW, look into your safe height and stop state while your in Auto Pro Setup.

Zucaticorp - I had your problem. The wire had broken free from the aluminum puck inside of the shielding. Use a multi-meter and check the resistance from the end of the plug to the face of the puck. If you get an "OL" or no numerical reading, then there is no longer a connection between the plug and the puck. I disassembled it, clipped off the frayed connection and re-assembled it with a new connector (at the puck). However, I now use the manual method and a piece of paper - this will never stop working ;-)

[ncsak]

Thanks for the speed suggestion. Brought the fast speed down to 1500. It seems to fail less. I'll keep playing with it this week.

It's not as critical now that I have a work around, (no long moves and using ZRN to reset Z when it happens between jobs.

I get with Axiom's techs next week to see if this is a known issue, something new, or maybe I'm doing something wrong.

[jwardy]

ncsak, something else you might look into - you mentioned it happens when you are moving the spindle with Z+/-. From the home screen, if you hit the stop/cancel button, you should see a list of speeds. I think these are specific to manual jogging of the gantry/spindle. Mine are set to x/y 2500 and Z is 2000. You can change those by selecting the one you want to change, deleting the value there and inputing a new value.

Something else that helped me, I changed my Stop State from the default to Back Home. This means when the machine is done running the file, instead of simply stopping and raising, it raises and homes everything. It's kinda nice because it gets out of the way of the work and for me seemed to completely solve the issue.

What do you mean by "ZRN"? I am unfamiliar with this feature.

[ncsak]

jwardy; ZRN(9) is above yellow OK button and allows you to individually home each axis. Thanks, I'll look at the Stopped State option because I usually home manually (OK button) when the job finishes.

[cehirschey]

Did you ever get the answer?  I have a similar problem from time to time on my X axis.  Get a grinding sound then stops moving, but the computer thinks it has traveled the correct distance.  From that point forward, the X axis is off and of course the project is destroyed.  


I have moved to slower feed rates and it fails less, but still happens from time to time.  Not to mention the fact that simply running slower than the machine is built for is not really a good answer.  


In my case, this can even happen when just moving the X axis freely across the gantry and not engaging the cutterhead or anything? This happens frequently (moving the x axis freely) to the far right side of the axis if running at the high movement speed. If I change it to low speed, it happens less frequently when moving freely, but still happens on occasion. 

[ncsak]

Lowering the speeds made it better; it also made the machine much slower but it seems to have fixed the problem. When I get time to play
with it I will start going back up on the speed.

I made one other change mentioned in another post about speeds being different than those shown in the bit parameters in VCarve.
I changed that option through the hand held controller. That really slowed things down but the machine now follows the feed rate, etc. in
the VCarve tool file. I can edit these depending on material type.

Right off I don't remember all the changes. The paperwork is out in the shop. I will get it tomorrow and do a follow-up post.

One other, and major problem, was that suddenly the depth of the X axis would increase, cutting thru the work. Changing the speed helped that.
It didn't seem to happen on up-spiral bits but almost always on down-spiral bits. The fast movement was actually pulling the bit lower in the 
chuck. I have started tightening the chuck much tighter and have not had any reoccurrences.

[redwood]

Regarding the bit slipping down, I learned this the hard way. Are you snapping the collet into the spindle nut? I for many years did not have a problem with bits slipping and last week it happened on 3 consecutive toolpaths with different bits and even with a different collet. Chad at Axiom asked be if I was snapping the collet into the nut and I said What. Anyways, sure enough the collet snapped right into the nut and I haven't had a issue since.

[jwardy]

cehirschey - what is the work speed and fast speed set at? Also, from the home screen, when you click stop/cancel, what speeds does it display? It's odd that it is happening on the x axis and at low speed - unless your low speed is set really high. Do you have dust collection - keeping the ballscrew and guides clean? And... how often are you lubricating those?

[ncsak]

chirschey

I set the Fast Speed from 3000 to 2000 (Menu, Auto Pro Setup, Work Speed, Fast Speed). Moves spindle more slowly but does not fail.

Changing the controller to read (instead of ignore) the g-code settings allows bit movement speeds to come from the g-code. This was
addressed in another post: Auto Pro Setup, GCODE Setup, F Read - Change from IGN F to READ F. 

It would be nice if the manual went into more detail on any of the options that can be changed, especially anything dealing with movement
settings. I've still got a ways to go to get a balance of movement speeds and bit performance but it's getting better.

[jwardy]

ncsak, the manual I received with my machine is pretty bad. However, I found an updated manual online that has more than double the content. Major difference is that it has a different controller than the one on my machine, but it seems that all the functionality is there. Check it out: www.axiomprecision.com/media/axiom-manual-basic.pdf

[ncsak]

The manual you reference is for the A11 controller. My machine has the B18 controller. The manual I have is the same date as yours but is for the B18 controller. Looks like the contents are the same except for the stuff related to the B18 HHC.

I got my copy off the Axiom page that allows you to build and order a machine. The manual is shown at the bottom of the features. (Auto Route PRO+ B18 Manual)

[jigsaw]

Had the same problem as ncsak. Adjusted the work speed from 3000 to 2000. That seems to have fixed it. Now after I do the tool set and run a program the bit stays above the work piece. I have 1/4" material and set to cut through at .280 The program runs but the bit starts about .8 above the material and ends .52 above material. Its like the puck is twice as thick. Is there a setting for the puck size?

[damonlayne]

Here is the Axiom Manual that shows the Controller Menu Layout (pg 33).
www.axiomprecision.com/media/axiom-manual-basic.pdf

On your hand-held controller, if you go to Menu - Machine Setup - CAD Thickness .... this is where you can change the setting for the thickness of the touch-off puck. It says the default is 25mm. Not sure why your setting would be different.

[jigsaw]

Yup I found it. I set it at 25.4 as that is actually 1". Thanks for the help. I also talked to Chad in support and he had me change the speeds on the X,Y & Z in three places to set my machine like he has his set and that seems to have fixed the Z axis issue.

[arsystems]

Dec 26, 2017 14:06:36 GMT -5 cehirschey said:

Did you ever get the answer?  I have a similar problem from time to time on my X axis.  Get a grinding sound then stops moving, but the computer thinks it has traveled the correct distance.  From that point forward, the X axis is off and of course the project is destroyed.  


I have moved to slower feed rates and it fails less, but still happens from time to time.  Not to mention the fact that simply running slower than the machine is built for is not really a good answer.  


In my case, this can even happen when just moving the X axis freely across the gantry and not engaging the cutterhead or anything? This happens frequently (moving the x axis freely) to the far right side of the axis if running at the high movement speed. If I change it to low speed, it happens less frequently when moving freely, but still happens on occasion. 

Ok I had this happen to me twice yesterday.  During a non cut rapid movement while moving freely across to the left, I heard the grinding and it stopped. The machine then believed it traveled the correct distance and began to reengage on the incorrect path ruining that part and wasting the material. 

This occurred with default controller settings, I have not increased the speeds as it happened to me when I did and I reset it to initial settings. I also checked the screws on the motors and they are tight. 

I would have to agree that running the machine slower to prevent this is not the answer. This machine is advertised at 200ipm and I set rapids or (fast speed) to that and it failed immediately. This machine is built extremely well and is more than solid enough to support 200ipm speeds.  Has anyone else experienced this or come up with a solution. 

[arsystems]

Just saw this in another post on here..

"Also, the Autorich controller does not like to use the high speed machine settings from Fusion without choking up a dust ball (means you have to set your fast speeds to 1500)"



Maybe this is a controller software error?

[smokediver576]

Feb 20, 2018 18:44:55 GMT -5 arsystems said:

I would have to agree that running the machine slower to prevent this is not the answer. This machine is advertised at 200ipm and I set rapids or (fast speed) to that and it failed immediately. This machine is built extremely well and is more than solid enough to support 200ipm speeds.  Has anyone else experienced this or come up with a solution. 

I would love to see one of these machines in person, running 200 ipm - 5000 mmpm. Heck, I would like to see it just cut "air" at that speed. Run from one end of the work area to the other with changes in Z. Unfortunately, this is one area that Axiom is giving some very misleading advertising. For me, to reliably cut molds for vacuum forming in tooling board I'm at 75 ipm max. My fast speed is set to 2000 mmpm.



If Axiom would adopt something like Linc CNC / PathPilot with some more robust stepper motors, they would rule the sub 4x8 CNC router world!

[arsystems]

Feb 21, 2018 8:24:27 GMT -5 smokediver576 said:

Feb 20, 2018 18:44:55 GMT -5 arsystems said:

I would have to agree that running the machine slower to prevent this is not the answer. This machine is advertised at 200ipm and I set rapids or (fast speed) to that and it failed immediately. This machine is built extremely well and is more than solid enough to support 200ipm speeds.  Has anyone else experienced this or come up with a solution. 

I would love to see one of these machines in person, running 200 ipm - 5000 mmpm. Heck, I would like to see it just cut "air" at that speed. Run from one end of the work area to the other with changes in Z. Unfortunately, this is one area that Axiom is giving some very misleading advertising. For me, to reliably cut molds for vacuum forming in tooling board I'm at 75 ipm max. My fast speed is set to 2000 mmpm.



If Axiom would adopt something like Linc CNC / PathPilot with some more robust stepper motors, they would rule the sub 4x8 CNC router world!

I am doing the same, using HDPE. I ran a cut the other day at 180 ipm and it cut like butter. However during a non engagement tool path I believe the Y axis locked up and ruined the cut.  The machines are strong enough to do it, I think there must be an issue with the motors or controller software. It may not have the internal power or memory to run gcode that quickly. 

[Deleted]

Just remember, stepper motors, which these machines use, lose torque as speed increases which is just the opposite of what you need. The Elite machines have servo motors which are more linear with speed and they quote higher feed rates as well. There are other machines out there that have higher feed rates and still use stepper motors but most publish lower feed rates, it's a matter of friction, load, and gearing.