Axis Knocking

Will try to keep this short and brief. Several months back I had a lightening strike that zapped my control computer. Previous computer was a Gateway I think, non Tormach anyway. I replaced it with a Dell. I took the old hard drive out of the zapped machine and put in the Dell. I had to re-install the mill software to get the mill back running, but ever since I have a knocking noise in all axis in either direction, while jogging or running a program. I have noticed that while referencing axis there is no knock. I have checked all I know to check and was wondering if anyone else has ever seen this problem. Machine is an older machine. Serial # 063. I have put in the upgraded spindle drive and have added a DIY 4th axis with a gecko drive. Again all axis knock when moving. Thanks in advance for any ideas that I should try.

Barry

What are the results when you run the mach3 driver test?

I ran the driver test and it showed some spikes but the green status bar showed system excellent. Not sure how to capture and post a screen shot. Machine ran fine on the other computer running windows 7. May just have to bite the bullet and format and re-install operating system.

Does even the 4th axis knock? What frequency is mach3 running at? Is it all Tormach defaults for sure?

yes even the fourth axis has the knock. Yes it all tormach defaults. I do have a stand alone version of Mach 3 that I opened up today and set up to run the mill. I only had a few minutes but I think it was running the mill without knocking. Will have to do more testing tomorrow. Freq is default to 25000 hertz. Will keep you updated on what I find. Thanks for your help.

The one thing I know can cause knocking is if you have the kernel khz set too high. Make sure it's at 25khz in the config file that's being used.

The kernel kHz may also be a function of machine speed (computer machine). What was the CPU speed of the old machine versus the new machine. I CNC converted a lathe and learned more about computer speed, kernel speed, and motor tuning than I cared to.

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Originally Posted by Jabs1542

The kernel kHz may also be a function of machine speed (computer machine). What was the CPU speed of the old machine versus the new machine. I CNC converted a lathe and learned more about computer speed, kernel speed, and motor tuning than I cared to.

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Correct Mach3 kernel speed has nothing to do with computer speed. 25kHz is well above the required step pulse rate for both Tormach machines, and nothing at all is gained by running the kernel any faster than required for the target step pulse rate.

Regards,
Ray L.

I would like to add to this subject
My mill at times kind of goes wonkey and bangs and nocks.
First time this happened I called tormach and they had me reinstall mach and it fixed problem and I was on my way.
It has happened a couple times after that and I found a faster fix in my case anyway!
I do complete shutdown of control computer and mill "including the red master power switch on side of cabinet"
This powers down all equipment completely.

Then after a few minutes power up and its fine! Way less work then install of mach or whatever!
After getting to know my tools better I could see where it had something corrupted and just needed to go dark to get rid of it.
Anyway hope this helps others get going faster when you have goofy issues like this.
md

I had the same thing on startup on one occasion, it made a banging noise as each axis was referenced, I thought it may be the accel decell function as it would start and stop abruptly, I shut down the system and rebooted and all was fine again.

Quote:

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Originally Posted by mountaindew

I would like to add to this subject
My mill at times kind of goes wonkey and bangs and nocks.
First time this happened I called tormach and they had me reinstall mach and it fixed problem and I was on my way.
It has happened a couple times after that and I found a faster fix in my case anyway!
I do complete shutdown of control computer and mill "including the red master power switch on side of cabinet"
This powers down all equipment completely.

Then after a few minutes power up and its fine! Way less work then install of mach or whatever!
After getting to know my tools better I could see where it had something corrupted and just needed to go dark to get rid of it.
Anyway hope this helps others get going faster when you have goofy issues like this.
md

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mountaindew and popspipes,
Do either of you have any external device or memory stick connected via USB during start up of Mach3? Or have any software running that might be trying to connect to internet or otherwise be time-sharing the CPU during the Mach3 start or when Mach3 is running.? These things have been suspect in previous abnormal Mach3 behaviour although some guys have no problems with these concurrent operations.

Bevin

Quote:

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Originally Posted by bevinp

mountaindew and popspipes,
Do either of you have any external device or memory stick connected via USB during start up of Mach3? Or have any software running that might be trying to connect to internet or otherwise be time-sharing the CPU during the Mach3 start or when Mach3 is running.? These things have been suspect in previous abnormal Mach3 behaviour although some guys have no problems with these concurrent operations.

Bevin

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I do have a bad habit of leaving usb memory stick in after shutdown and possible startup!
I will have to keep an eye on that.
Thanks for tip!

As for other software that is not a problem . I setup my own controller from old workstation and fresh software stack. I know exactly what is installed. "nothing but root o.s. and mach "
With all settings in both bios and o.s. have been specifically configured to make the machine a stable controller.
Im planning to build a couple more controllers from fresh new top bin parts next month. One for tormach and one for a router, I think.
I want to use newer technology with few or no cooling fans and small form factor. "dust free and less then 80w power use is goal"
md

Just to update on this problem. I still have no idea what was causing the bumping noise. I tried a total of 6 different computers, some with fresh installs of windows 7 and some with old installs of windows xp and all but two had the bumping issue. All pcs were Dell computers except one. There was one dell that appeared to run the machine with no bumping but it was a very small form factor and I was just afraid it would not last. I replaced it with a 3ghz lenova pc and a fresh install of windows 7 and all is running fine. Again I have no idea what was causing the bumping in the steppers when they were moving. I would like to say thank you to all that replied and wish I could answer questions but I am at a loss. All seems to be fine now and hope it stays that way. Again thanks to everyone. Awesome forum!!!!!!!