Novaturn having problems returning to home.

TimPower · Post by **TimPower** » Wed 25 Apr , 2007 10:16 am

Hi there,
I am having problems at the moment with the machine not returning to zero. When homing in the X axis it just gets near the sensor then it freezes emitting a high pitched noise till I hit the Estop and then home it again. I doesn't happen all the time but maybe once every third time you home it. It doesn't happen when you use an M06, only when you hit the home button manually. Should I just slow down the rapid speed or is there some adjustment I can make to the sensor. Is there a pot on an amp for the sensor somewhere. In both the X axis and Z axis sometimes believes that it has homed and then when the next tool comes in it machines in the wrong place.
Any tips on how to stop this.
Cheers,
Tim Power.

Martin · Post by **Martin** » Thu 26 Apr , 2007 7:16 am

You have not said what version of software you are running from.

If it is a older machine that has been updated to VRTurning you need to update to the latest version. I think it is now ver1.17. I know some of the earlier versions had toolchange problems.
I have had to alter both the steps per mm & max feed rate when updating some of our earlier Novaturns from Dos to VR Turning.

It may be worth looking at the mechanics of the X. If you turn the pulley with the power off you may find the X axis is slack, & need to adjust the gib strip.

Post by **Denford Admin** » Thu 26 Apr , 2007 8:52 am

Could just be that the home switch is failing / got dust inside it / has moved / got a broken or loose wire

Don't ask me where the switch is, but I'd take a close look at it first.
If you can operate it manually, you could test its operation a number of times by hand (carefully

)

Martin · Post by **Martin** » Thu 26 Apr , 2007 16:54 pm

I belive that the Novaturn has Datum SENSORS fitted.
Some had a red/green LED on them that you see change when activated.

TimPower · Post by **TimPower** » Fri 27 Apr , 2007 10:13 am

I'm wondering if my PC is too slow for the signals coming back from the machine. It's a 1Gig machine and there is plenty of memory in it but when I have the task manager up it shows that the CPU is running at 100% when it is changing tools and up in the 80's when doing most operations. What size PC's are normally used for running denford software? I'm wondering if this is what is causing the m/c to lose it's home positions. It certainly seems to be what causes the m/c to time out which requires me to shut down the program and start up again. This used to happen if I changed the feedrate % while it was indexing so I now don't touch anything till it has indexed, but it makes me wonder if I am constantly opertaing at the edge of the PC's capabilities?
Cheers,
Tim.

Post by **Denford Admin** » Fri 27 Apr , 2007 10:41 am

VR turning should run fine on a P3-500 - it used to in the past when these where the norm.

Is something else is going on with your PC ? - take a look at the processes using the CPU in the task manager.
If it is VR Turning using all the power, when connected to the machine, then it could well be a RS232 communications problem and its struggling to send and receive data efficiently.

Maybe try a different COM port, and check that no other software is trying to use it.
Try things suggested here:
viewtopic.php?t=544

Denford Software & Machines

Denford Software & Machines

Novaturn having problems returning to home.

Novaturn having problems returning to home.

What spec PC should I use for V1.16?