Handle Jog Pendant

[stang5197]

Has anyone had problems with the handle jog pendant on the Haas VF series mills? I have a problem when moving the axis for stops intermittently and is very jerky. It appears to be something to do with the feed rate selector as when you look at the screen the feed rate flashes from 0.001 to 0.1. The problem happens with all of the individual axis, put the cycle start and feed hold buttons work fine.

I pulled the rear panel off the main operator panel to check for anything loose, etc. but everything was still siliconed tight from the factory. I am going to take the pendant apart to see if I can trace down the problem from there, just curious if this is a common problem with Haas, or if anyone else has a solution for the problem.

Machine is a '01 Haas VF0E

[qualitytool]

I had to replace the cable to the remote box it was not cheap

[stang5197]

Do you remeber about how much it was? Just want to make sure we don't get hosed on the cost.

Before you changed the cable did the other functions work or did it die completely.

[Geof]

Originally Posted by stang5197 Has anyone had problems with the handle jog pendant on the Haas VF series mills? I have a problem when moving the axis for stops intermittently and is very jerky....

Do you mean that sometimes when you turn the handwheel the axis moves and others times it does not move; it is not entirely clear what you mean from that sentence.

On one of my machines the pulse generator driven by the handwheel was not working smoothly and sometimes it was possible to rotate the handwheel a full turn without moving the axis.

What I did was put the jog select on the slowest setting and turn the handwheel very fast backwards and forwards. There are contacts inside the pulse generator and my idea was to operate them many, many times to try and clean them. These contacts only switch very low currents and it is not uncommon for switches operating on logic level currents to malfunction.

It seemed to work because the handhweel moves the axes okay now.

[Al_The_Man]

Generally the Handwheels are identical to optical incremental encoders usually 100p/turn, You can pick up Fanuc or others on ebay, the only think to watch for some are 12v input, some 5vdc.
You can use an ordinary 100p/turn encoder but if you do not use the existing mechanism, you do not get the indent feature.
Al.

[stang5197]

Geof,
I think we are on the same page. If you select Z axis and 0.100 (for example) and turn the handwheel Z will move and then stops and then starts again.

When using the axis jog on the control panel it works perfect.

I give what you said a shot later today and see if that helps. It has gradually gotten worse over the last week or so.

[Geof]

Originally Posted by stang5197 Geof, I think we are on the same page. If you select Z axis and 0.100 (for example) and turn the handwheel Z will move and then stops and then starts again. When using the axis jog on the control panel it works perfect. I give what you said a shot later today and see if that helps. It has gradually gotten worse over the last week or so.

I didn't know they were normally optical as Al says but what I did worked, at least until now. I haven't used the machine for two weeks so when I want to use it tomorrow it will probably not work

[stang5197]

Geof, I tried your trick but I wasn't as lucky.

Is there any way of figuring out if the cable is good or bad or if it is in the circuit board?

Now the when the Z axis is selected on the remote, the main operator screen doesn't recongize it has been selected. When all of the other axis come up on the screen. The other thing is the feed rate doesn't come up on the screen no matter what axis is selected.

The cycle start and feed hold bolts work fine, so I am not sure if it is the cable or the circuit board in the pendant.

[serviceman]

you can buy the rotary switches instead of paying 400 dollars for the faceplate which comes with the switches the switches do go bad if it is the cable you should see the problem when you flex the cable. if you know how to solder.

[fourcylthrill]

We had this problem a few years ago. It was a short in the cable right when it comes out of the pendant. When I explained the problem to the tech, he knew right away what was wrong. He said it was a common problem. Try jiggling the cable around at the pendant. Our pendant would only work when we turned it upside down. You could also take the cable out and do a resistance check on it to be absolutely sure. I can't remember the cost to repair.