X Axes movement is sporadic and incorrect

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Kholden
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X Axes movement is sporadic and incorrect

Post by Kholden » Wed 08 Mar , 2006 14:56 pm

Q: The safety switch (datum microswitch) came loose on the X axes and the machine jammed going to the home position. The motor wires were reversed to move the axes so that the switch could be reinstalled but now the movement is not correct. After homing the machine, pushing the right arrow key moves it right, let go and push it again and it goes left. After jogging to a position for the offset, going home the X axis goes in the opposite direction. We have tested the switch and it appears to be working correctly. Can the lead wires be backwards, can it be bypassed to test axes movement.

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Kholden
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X Axes movement is sporadic and incorrect

Post by Kholden » Wed 08 Mar , 2006 15:02 pm

1. Check the wiring from the datum switch to look for damage

2. Check the position of the switch, does the X axis actually depress the datum switch enough to cause the contact to change over? by slackening the Datum switch screw you could try to reposition.

3. Try the secret button to get the JOG tab and see if the axis will jog in both directions:

Double mouse click the following areas
VR Milling Ver 5 (Between X and XYZ buttons)
VR Milling Ver 2 (Between “Z Axis ONLY” and “HOME ALL” buttons in the LEFT margin horizontal to the gap in between the two buttons).

4. S witch the faulty axis plug on the drive board with the one you know works. If the fault then moves onto the other axis then the drive card may be faulty.

On drive / controller board in control box or machine itself
Far top right Orange Plug / Socket - X-axis
Far top right to the left of X-axis Orange Plug / Socket - Y axis
Far bottom right Orange Plug / Socket - Z axis
Kevin Holden
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Denford, Inc
kholden@denford.com
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Steve
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Post by Steve » Wed 08 Mar , 2006 18:14 pm

If the machine has failed to home correctly and you need to back off the slide refere to the post on secret home button.

This allows you to jog away and rectify the problem.

If you have reversed the axis direction by switching a motor phase then refer to the post on Axis motor direction.

If the motor is sparadic or suns in a random direction this could be due to a bad motor connection or damaged motor lead. It could also be caused by a fault in the drive card. Switching two of the motor drive outputs from the drive card as mentioned above would identify where the problem is. If the fault remains on the axis that it was on before when being controlled by the jog buttons for the other then the fault is in the motor or wiring. If the fault transfers to the other axis then the fault ison the drive.

If Random motion is detected in all the axes then it could be that the power supply or drive card are faulty.

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Steve
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Post by Steve » Wed 08 Mar , 2006 18:21 pm

Random motion could also be caused by a stall of the slide.

Check that the slide is clean and free of obstructions.

On routers only lubricate with a dry silicone spray. Wait for the spray to dry before operating the machine again.

On Milling machines and Lathes ensure the slides are well lubricated with light machine oil.

shakey j
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Post by shakey j » Tue 21 Mar , 2006 22:32 pm

I have today developed a similar problem on my Triac (Serial No: TR13106 C)
When searching for it's Y reference point it is travelling backwards and hitting the limit switch for Y-
I had thought this could this be due to a faulty proximity switch, if so is there any way of testing this? I have by chance
found that by pressing "T" on the control panel I can get to a diagnostics page which shows me that the limit switch is working fine but is there anything to show that the proximity switch is working correctly?
Should I try swapping the X and Y drives over to check for a fault there?

Sorry Mods I was going to post this in a thread of it's own until I spotted this one :oops:

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Steve
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Post by Steve » Wed 22 Mar , 2006 1:02 am

I suspect that it is a home switch problem. Am not sure on the diagnostics.

The first thing to try is the SECRET HOME BUTTON. I suspect you are using VR Milling 2.

See seperate thread on this. If you use this function you will be able to jog the axis without having to first home it. This will prove if the axis is OK. Once you have jogged away press in the home switch a few times just to see if it is sticky. You may want to measure it with a meter.

Good Luck!

shakey j
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Post by shakey j » Wed 22 Mar , 2006 8:01 am

Steve wrote:I suspect that it is a home switch problem. Am not sure on the diagnostics.

I suspect you are using VR Milling 2.

Good Luck!
No my Triac is an older one from 1986 so I suspect there are no secret buttons there?

Thanks for the reply

Mark

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Post by Denford Admin » Wed 22 Mar , 2006 10:38 am

I'm pretty sure the Y home switch is a proxy on those Triacs
It sounds like the switch is ON (sensing) all the time if the axis travels the wrong way when starting to home.
For the age, I would guess at a faulty proxy switch, or broken wire under the table.

shakey j
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Post by shakey j » Fri 24 Mar , 2006 20:56 pm

Denford Admin wrote:I'm pretty sure the Y home switch is a proxy on those Triacs
It sounds like the switch is ON (sensing) all the time if the axis travels the wrong way when starting to home.
For the age, I would guess at a faulty proxy switch, or broken wire under the table.
All OK now, a main plug had worked loose (the one that has wires running to the bottom of the control board)
I've just finished soldering the proxy switch back on :roll: and all is well again. :lol:

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