[Steve S]

We have an older 4020 vmc with fadal cnc 88 controler.
when drilling it will sometimes go's to wrong position, starts to drill, then it will try to go to correct position, causing crash, or while milling, feed will hesitate, then rapid over to where it thinks it should be; not good.
This problem is intermittent, we have had techs out swapping cards, jiggling wires etc., Problem doesn't happen when they are around. can anybody
help?

[ASIGuy]

Steve,

I would look at isolating the problem. Is it in the X, Y, or Z? Both axes, multiple, ect. If it's totally random, try cleaning and reseating all boards. Take them out and use a school erasor and erase all board ends that plug into the 1060 motherboard. I think they call those "Pinky" erasors. Also take the white plugs out, use contact cleaner and doushe them all out. Make sure they are dry before reconnecting.

If it's only one axis mostly or always, then let's look at a bad amp card, controller card, wiring to motor, or motor components. Swap amp cards and see if issue moves, and then swap motors to confirm if necessary. Use logic and you will nail it. Fadal's are one of the easiest machines in the world to troubleshoot.

[Steve S]

ASIguy, thanks for the response, the problem is random and on all three axis, I'm working on your suggestions and will let you know how it works, thanks again

[ASIGuy]

Steve,

If it's random, suspect the DC power supply, 1030 card, or 1400 card. As far as the cards go, inspect them and make sure they are clean front and back. If needed, use contact cleaner to spray them down, make damn sure they are dry then plug them back in and see how it works out. Also, if you are welding in close vacinity, stop! RF from your welders, in particular Tig welding can cause havic on the control. If you cannot help welding close to the machine due to shop logistics, then call FadalCNC.com and buy one of their CNC grade surge supressors. That will likely solve any electrical noise issues. Good luck.

[Steve S]

ASIGuy,
I cleaned and reseated cards in1060 board. I ran machine for an hour
with no drill, and nothing bad happened. When I loaded a drill it promptly
wiped out. It went to wrong position,started drill cycle, then moved. Some while back, while running a 1" e mill the feed started to hesitate, I hit the feed hold button, and machine still jerked over to where it thought it should be, even with my hand on the red button.
This is a fab shop, and we do all kinds of welding, a tech mentioned the possibility of interference before, I have never been able to correlate any welding activity, and macine problems though. Other cnc's are unafected.
I found a 1040 board plugged into mother board. Is this a power board? it has a communication ribbon plugged into it. could not locate a 1400 board

[Neal]

Steve--
Have you verified your main machine ground? Also make sure the it is clean of AC ripple up to .05 volts is acceptable.

Neal

[Steve S]

We had our electrician here thursday, he found a loose connector going into the bottom of the mother board in slot #5. also low voltage on the x axis amplifier card. we have a card coming and i'll let you know.

[ASIGuy]

Good call Neil. I suspect the loose connector will resolve your issues. Sounds like noisy power. All machines hate this!!

[Steve S]

We have been up and running about a week now. No problems yet, thanks for the help, Steve

[Tate]

I just had a similar problem. I was cutting out a pocket with a 1" end mill. The light inside flickered twice and the spindle stopped. I started evertthing back up again and ran it for about 1 minute. I hit the slide stop button, turned off the spindle and coolant while I checked the cut when the table started to move in a random XY arc. Boss told me to reboot the machine and try again. This time it made it thru two pockets and half way thru cutting a side to an angle the table stopped moving, the spindle and coolant stayed on and the monitor was blank. I turned it off and will call Fadal in the morning. I hope it was just a power supply going bad.