Jung F40 prolems with table movement

I have an old Jung F40
For a while it functioned as it should
But now the table movement does not work propperly

It has 2 pushbuttons One to move the tale to the left and one for the right These are actuated by a adjustable cam for each pushbutton
If the cam actuates its designated pushbutton the direction of the table is reversed
The problem now is that the leftside button only functions at very low speed
At higher speed it overshoots These puschuttons are electrical The electrical functions I checked and are fine

If I put the speed all down and actuate the buttons on the right one I here a noise from a valve probably
On the right one I here the same sound but it sound like the valve actuates slower
Anyone else had that problem and knows how to fix it

I hope I don`t have to take it apart

Peter from Holland

Hi Peter

I have a similar problem. There is a rod in the spool-valve that actuates a microswitch that is out of adjustment.

It is in a very difficult location to get to. I haven't been able to complete the work on my machine since I blew my back out last winter because the posture required to reach the part is now impossible for me. I think I will eventually have to take the oil reservoir out to complete this job.

Here is the schematic for the switch and reversing solenoid:



And its location:



I have some documentation for this machine, but not for the hydraulics.

Rgds
<jbc>

Hello Rgds

I took out the tank and you could reach for it then but you are unable to adjust that microswitch then
So you can just as well leave the tank where it is
I took out the whole hydraulic control For that you have to take out the Y axe spindle and remove the speedadjusting leve,r some bolts on the front and the lever that is actuated by the stop dogs on the Y axe

With me it turned out the solenoid was toasted See how one half hat gotten very hot
it is 2 solenoids in one housing one to push one to pull
Even a piece of the terminal block is melted away completly
so now i eighter have to find another one or have this one rewound
I think I do the last as thats probably faster
But if anyone has one lying around please offer it to me


BTW Binder still exists and i got them on the phone but that type they did not know
I send them the pics and they would get back to me
But I have sold the machine and it should get out monday or so

Peter from holland

peterve said:

But I have sold the machine and it should get out monday or so

Peter from holland

Click to expand...

Damn, your fast.

It'll be a while yet before I crawl up in there. Nasty tight job.

peterve said:

For that you have to take out the Y axe spindle and remove ...

Click to expand...

Hi Peter

Re-reading your response, I suppose that this repair/adjustment is a good opportunity to replace the traverse feedscrew bellows? I probably should pre-order that part before I proceed?

Thanks
<jbc>
.

The machine is running again
Yesterday we had the solenoid back Both coils were rewired and one had a new base
Within 2 hours we had it back running
Today it will be shipped


Peter from Holland

Hello,

I've purchased a Jung F40 from an auction recently and last weekend got the power hooked up on to it, and there were couple problems, loose-ish wires under the X axis travel reversing buttons, that intermittently worked, that was an easy fix, but I noticed that the hydraulic feed at one travel end is jerky, like there was something holding it and it was difficult for hydraulics to start the table motion (left to right=ok, right to left start is where the "jerkyness" is happening), and sure enough there is some oil leaking from the left side of the X feed cylinder (C points to the spot in the picture), which suggests over pressure and leads me to think of some blocked or malfunctioning valve somewhere.

My guess is that the problem might be with the solenoid actuated valve described in this topic, I pulled the hydraulic tank and visual inspection suggests that the solenoid itself is ok, both feeds work at equal speeds as well, I have no manuals for the machine, so I had to guess which lever does what, and the little lever on the right (B) seems to be to release all pressure in the feed system to be able to jog the X manually, and when I use the lever then I can somewhat easily move the table to the left, but to the right a pressure build up can be felt, and after around 100mm of travel the pressure becomes too great to overpower with the X hand wheel.

The Y axis auto feed works fine in both directions.

Since the solenoid actuated valve is quite difficult to get to, the Y xis has to be disassembled and other stuff removed before access can be gained, I wanted to consult here and ask for opinions, and maybe someone even has a hydraulic diagram for the machine, and electrical as well perhaps? (google wasn't much of a help, it did find this thread though)

thanks, J

That could be air in the hydraulic line, are the oil levels ok?.

that is what I thought as well at beginning, the oil is quite low, but it doesn't make the usual air-in-oil sounds, and otherwise it is functioning normally, and the other thing is that there must be a mode where oil is allowed to circulate from one side of the X feed cylinder to the other to allow manual operation of the X axis, and that is what I think the little lever (marked B) does, at least, when it is flipped up, it releases something in the control box and the X feed doesn't work any more until the black round button is pressed (the B lever "resets" the button), but when that little lever is operated, I can feed the table to one side with some effort, but the other direction gets progressively harder until (pressure build up) in a space of around 100mm or so it can't be moved further

That is what I was able to figure out without any manuals, that is why I'm asking here if someone is familiar with the normal modes of operation of this machine.

Else I will have to tare it down to figure out what is not working like it should, I would do it anyway, since it needs new paint, old one has turned into a dirty, sticky mess, Y feed screw bellows need replacing, check all oil passages, check ways for wear etc, but I wanted to make sure everything works before I take it apart...