Reference origin point lost. I think it is as bad as I can imagine

I was doing a boring operation that would take about 15 minutes to bore. About 8 hours into the part. 10 minutes in, I hear 'Wong Wong Wong' as it is cutting unevenly. Stop machine. See bore is not cutting on one side. Stop program and try to go to manual.

"Error: Unable to change mode. Origin Point Unknown" (or something close to that. I did not take a photo)

Remove part. Turn off machine, turn on. Can't get out of program mode. Turn off, go to manual mode, turn on. X axis origin point has been lost and shows up in red. The spindle had moved about 1" in the X during the period of time when trying to assess the damage. Re-home the X axis. Done. All that is lost is the part I was working on.


This is the first time I have done boring operations and I did a test first. Not as deep a bore, or one for as long a time frame of 15 per bore. I have never seen a time when I had to re-home an axis. As well, as this was boring, the machine was not moving in the X axis as it was to stay stationary.


My thoughts are:
1. Scales are dirty.
This is an old machine. Maybe somehow there was a bit of dirt that gave a bad signal to the encoder that could have caused this. Is this possible? Is there a way to clean the scales?

2. Boring head overloaded axis.
Looking at the part, I wonder if when I bored the hole with the end mill it taped the hole (3" deep 7075 aluminum, 4" diameter). This was my first pass and I was doing a 8 thou engagement. Towards the point of failure it was getting up to (my estimate) 20 thou engagement. I didn't expect a taper in the hole. The machine was running at 25rpm and 0.2ipm. That speed and feed produced a good finish on my test piece, but not so much on the finished part. I had setup to take off 100 thou diameter with the boring operations. This low rpm is hard on a motor and I wonder if the torque and force was too much, moving the axis without motor input and causing the control system to not understand what is going on.

3. Oil
This is an odd idea from my manager. The mill has an oil tank reservoir spyglass that shows the oil is near the lower end of the tank but still has some ways to go. The hydraulic motor had some issues in the past and the oil detection switch was wired stuck on as it would not pump even with oil present. As well, the hydraulic pump has 28Ω/28Ω/3.8Ω across the three phases as we measured it when we got a new relay to turn it on. The pump still works and still generates pressure. He considers this an important point to bring up, but I don't think the mill uses hydraulics in the X axis.

The mill is a Deckel FP50CC/T. Looking to see if anyone has had anything similar. Also, anyone know where I can find decent FS for boring 7075?

Vitran said:

Is there a way to clean the scales?

Click to expand...

I have ZERO experience with Deckel NC machines, so I have no idea if your problem is scale related. But yes, assuming that these are Heidenhain glass scales, it is possible to clean the scales. Once they are on a table or bench in front of you it takes an hour or two. See here for a detailed scale-cleaning report.

More information would help.
What control???????????????????

"X" axis is moved via servo motor....nothing to do with the hydraulics....
When you say hydraulics, are you talking about the pumps that make pressure to change tools and the like or are you talking about the pump that supplies lube to the machine slides and screws?

Believe that machine uses Heidenhain glass scales....Pretty sure the machine has error detection that will fault if the scales are dirty of faulty....

When you noticed the tool cutting out of position...was the readout for location displayed on the control correct, of did it show the position as being moved....(did if show where it really was)

Are you running this job horizontal of vertical?
Cheers Ross

AlfaGTA,
- This is a Dialog 11 controller.
- The X axis is moved via servo motor. I am fairly certain there is no hydraulic interface on the X axis, however was suggested to add that information in case it was relevant. This is the hydraulic pump that drives the tool changing, spindle changing, z axis counterweight.

- When I noticed the tool out of position, it read that it was in the correct location. I let it turn once more (with a grind) before stopping the program and trying to go to the manual control screen and retract the tooling. It was then that it told me that it had lost the reference origin point and would not let me change screens. When I turned off and on the power to the servo side of the system to get back to the manual controls, the display screen showed a red 0.0000 on the X axis and green on the other two axis. The red 0.0000 signals that it needs to find its reference point. I then let the machine move to the X reference point.

I am quite shocked the machine did not stop the program or alert me when the X reference point was lost when it was running.

- This operation was in the vertical axis.

Thanks fro the quick response and filling in the blanks.
Alas no help here, ignorant with the Dialog11...Sorry
Cheers Ross