Z Axis not functioning (newbie)

[dollarbill165]

I'm at my wits end here... I'm hoping one of you seasoned SB'ers can bring some sanity back into my life. I just setup my new benchtop standard a couple weeks ago so I really need some help. First... SB had to send me a new z axis driver once I set up the machine the first day (I'm thinking this is not the way to kick things off). Today the z axis just stopped functioning entirely while running a 3d file. I noticed right away that something was wrong and stopped the file. I thought the machined skipped so I thought I'd slow the cutting speed and rerun the program. Well, I hit the JH and snapped a new 1/8 inch bit (cried a little). Then decided to restart the program and run it in K mode. Well, the program registard the movement but the z did not move (which is why the bit broke). Anyhoo... sorry for such a long posting. Can anyone help me? I'm going to order some new bits now. Thanks again,

[fleinbach]

Did you check the pinion gear to make sure it is still tight?

[dollarbill165]

I'll give that a check to make sure it is...

I went back and rebooted the computer... no change. Then put it in preview mode, shut down the controller and restarted it. Then switched back to move mode and now the z axis works.

I'm still baffled, is it my computer causing this or the controller? It's not the first time I've had this file skip.

[harryball]

Not sure what's happening, but is it possible that at some point this file is stalling the Z axis by trying to raise it too far? I ran into that once... but if I recall everything stopped moving and I had to reset the controller, not just the Z.

Robert

[dollarbill165]

Well, I'm not sure, but I don't think so. I'm zeroing it on the table, not the block and the safe z jog hight is 1.75 well below the top limits. The block I'm trying to cut is 1.5.

I'm wondering... a couple of days ago I tightened one or two of the v bearings on the z axis because I could move them with my fingers. Could I have tightened them too much, causing the z axis to bind?

[richards]

Bill,
I mark all v-bearings with a black permanent marker stripe so that I can see at a glance whether the bearing is turning or not. I had some slop in the Y-axis some time ago because at certain points, one of the y-axis v-bearings wasn't contacting the rail. After a quick adjustment and the addition of the markings, I can tell at a glance whether any/all bearings are turning.

[dollarbill165]

Thanks Mark... that's a great idea! I'll try that. I noticed yesterday that one of the tightening bolts didn't seem to snug-up. I didn't keep turning it for fear it was stripped. is it hard or complicated to remove that one and inspect it?

[fleinbach]

Bill

If you tighten the v-bearings to much you will have problems. The bearings need to be tight enough to take out any movement but not so tight that they hold the Z up. I tighten mine until they are holding the Z motor up and then just back off enough so it will fall freely.

[bob_lofthouse]

I've had a couple of problems with this myself where the Z axis will not move.. Even in Keyboard mode.

I deleted the config file and everything returned to normal.

When this problem has occurred deleting the config file has corrected the problem everytime...

[mikek]

Bill, I had a problem at first with my benchtop with the Z axis. It was intermittant connection(s) in the shrinkwrapped connector. Looked like someone had carried the motor by the cable and pulled loose the connections. I could not see it but found it accidentally when I bumped into the cable and the motor reacted. Shut down power, fixed connection, problem solved. If you can mannually move the z axis with the keyboard smoothly up and down (several times), that should eliminate intermittant contact issues. You might try adding a good frame ground up to the Y Car also.

[tree]

Bill, sounds like the problem I was having. Do you have your control box where it can freely breathe? I was having problems with heat. Would work fine, but the drive control would thermal out and stop. I took the side of the control off and installed a fan that blows directly on the drives and it has never happened again.

[dollarbill165]

Wow... those are some really good solutions. i thought I had the problem fixed, but then I ran another lengthy 3d file and it happended again. It seem to happen in the later parts of the file so heat may be an issue. I am in my garage so I think I'll try the fan next.
Thanks to everyone... I'll let you know what happens later today.

Bill