What would be a reason for clunk clunk

[seanreit]

clunk clunk clunk on all three axis and it is not all the time, it is interment.

And when it is happening, I skip steps like crazy, even when trying to reference all three axis.

If I go away and come back later, the problem may or may not be there, I'll get a few hours of run time and it will run perfect, and then from no where, clunk clunk clunk ON EVERY AXIS.

Anyone see this before?

[fastlanecafe]

If it were only 1 axis, I would look for a loose motor drive pulley or coupler, or a loose leadscrew bracket. But if its in all 3 axes at the same time- look toward a stepper motor " boot"- like when you first power up the computer. You might have a software or hardware problem sending a ghost signal to the motors. Something like your backlash compensation kicking in randomly.

[BlueFin]

Do you have all automatic things turned off in your computer? If your computer tries to automatic update it's Microsoft OS or the anti virus tries to do something you will get hiccups in your signal to all of the axis's. Do you have the ferrite choke on your printer cable? In the manual there is something about setting your network adapter to a single speed and not allowing it to automatically pick a speed setting otherwise the drive motors will tick as they stop and restart during this searching.

[Dennis Bohlke]

Since it's common to all three axis, I would suspect power supply or software driving the machine.

If you are using Mach3, I would suspect it is being interrupted by some other program on the computer.

Dennis
www.super-tech.com

[zephyr9900]

I'll echo what the other guys have said about unnecessary software. If you haven't gone through the Windows optimization in Appendix 3 of http://tormach.com/document_library/...-3-UM-C4.1.pdf , do so. Besides Microsoft background processes, Adobe Reader is especially bad. If you're not really careful about disabling all its background auto-stuff it's better to not even have it installed on the Tormach control PC. I might be extreme (maybe "might" isn't a strong-enough word ), but the only things I have installed on my control PC are the PCNC software itself and a text editor (I don't like Notepad so I use my favorite.)

Another possibility is electrical interference. Tormachs these days come with a ferrite RF supressor on the parallel cable, and they sent me one a while back to retrofit onto my cable. I have machine 10000000B which is a little over two years old now.

Best regards,

Randy

[MichaelHenry]

I had a problem like that a few weeks ago on just one axis of my mill. The mill hadn't been used in a few months and at first I thought the problem was due to dried spooge on the X-axis ways. The clunking/missing steps did improve a bit when the spooge was cleaned off but di not disappear completely. Installing a new X-axis driver did fix the problem permanently.

If you have at least one axis that is working properly, try swapping out that driver for one on an axis that is not working properly. If the problem switches axies you will have found the source.

Mike

[thackman]

Did you run XML tweak or install an updated Tormach release of Mach3 recently?

I installed their VFD upgrade kit which required an update to mach and I an major issues with the x and z axis after the install. The mill was clunking and vibrating so bad that I thought the ballnuts seized up. I could feel the vibration right through the concrete floor. Turns out there were a few settings, Pulse width and a few others, in their Mach config that were wrong. Most of the time I couldn't get to do a ref home. I switched back to the previous profile and everything was fine. They are looking into the problem now to figure out which settings were changed and how they got out.

[seanreit]

Interesting responses all, and thanks. I have been using a friends Tormach for almost two years, and finally got one, and then these little problems, for instance, on the z axis gib, I was bottomed out at the top as far as the screw would go, and not tight enough, I had to put a piece of 1/4" metal down the hole to push against the gib and the screw. And the Y axis is missing steps about once an hour of run time, intermittent. No software on the running computer other than pcnc and firefox. I have three computers in my shop, so I'm not lacking for places to watch internet porn j/k.

I do not have the ferrite ring, so I will look into that. The clunking has become less and less, it is now happening about three times every four hours of run time, and only a few clunks at that. So I'm at a loss. The step loss has gone pretty much away. But it was never on just one axis, always all three at a time in movement.

I'm like the guy above, I thought surely something was locking up and pushing through it. Scared me!

Thanks again for the many different ideas.