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asto
13-04-2013, 03:36 PM
Hi everybody!

Just before yesterday I bench tested my Orac and it was running fine.
So I moved to the next step which was to put everything back in place and start cutting.

But the machine did not like this idea and what I am getting now is...Drives glowing nice green led each and the distinctive oscillator sound that says we are ready to run your motors. Then I select manual mode and pressing arrow keys to move the selected axis, the screen shows actual coordinate position changing but none of the motors is willing to spin.
One of them I tried turning by hand but could not. This one generates strange and varying oscillator sounds even tough is immobilized. And the second can be turned by hand almost effortlessly.

I am sure many of you guys here can view things to which it looks I am totally blind. As considering all current machine symptoms I can not even come close to what may have caused this problem.

Any advise and help is highly appreciated.

regards

!874787488749

Swarfing
13-04-2013, 03:42 PM
If the motors are energising then could be wiring on one of the stop/ limit circuits. Check all connections again would be my suggestion. I've been there when i have checked connections a million times just to find it was still a connection issue. look for trapped insulation, stuck limit switches (use some switch cleaner).

asto
13-04-2013, 04:03 PM
That's what came to my mind first and bridged the limit switch inputs at the controller. This sort of thing did last night but things did not change.
So i keep searching giving particular attention to the points you mention Swarfing.

Thanks!

Regards

John S
13-04-2013, 04:54 PM
Can't really help but just remembered I have an Orac here somewhere, don't laugh but according to small son we have 15 CNC machines here somewhere in various stated of undress.

Anyway from what I remember after we collected it from Oxford, plugged it in to try it and it was dead but the spindle would run. If you find out what's wrong I'm quite prepared to rob this for spares but it is an unknown item.

http://www.stevenson-engineers.co.uk/files/ORAC1.jpg

asto
13-04-2013, 05:17 PM
Thanks John S!
I can count on that.
It seems to me yours carry a power chuck.

John S
13-04-2013, 06:20 PM
Yes it has standard chuck and air chuck.
Problem with the air chuck is no hole down the middle so limited to cut pieces but at least I can swap it.
I have a small Sieg KC4 lathe at the moment but the Orac is a bigger and beefier machine.
When I get it converted it will replace the KC4. Idea is to run it on Mach with a Kflop to do the spindle timing for threading.

birchy
13-04-2013, 08:38 PM
@Asto:
Given that you have THIS issue AND your spindle drive problems on the other thread, maybe it's time to consider bringing that machine forward 30 years with an upgrade to more modern control?

asto
13-04-2013, 11:19 PM
I am not going to hide this. You are so right Birchy. The point here is that a friend of mine is waiting to receive parts and promised him we start this Monday.
Now he is about to see me ling to him.
Best way of course would be to possess an industrial cnc but at the moment I can not afford this.

cheers

birchy
13-04-2013, 11:25 PM
Well....you have 2 choices:

1. Confess that your machine has broken down and you cannot repair
2. Sub contract the work to another company

Swarfing
14-04-2013, 10:14 AM
I have to be honest Asto the gains in changing the electronics will save you a lot of heartache and future expense. You have 30 year old electronics and it will repeatedly breakdown on you. You could get some money back from selling the electronics you have. There will always be somebody that is willing to give it a go and put that towards new stuff. Your steppers should be fine and you could utilise the power supplies maybe?

asto
14-04-2013, 10:14 PM
Thanks for the advise Swarfing. I have plans for this but it is not the right time for me to upgrade. Someone is waiting parts to make with that lathe and making profit this way then I can replace the old electronics.

Swarfing
14-04-2013, 10:17 PM
No worries Asto, hopefully there is somebody with more experience of this machine than i have here that can help you get this working.

asto
14-04-2013, 10:51 PM
Thank you. I'll appreciate that.

phill05
15-04-2013, 12:39 PM
Asto,
Have you had a look at the interlock on the key/stop button I understand you turn the key to the right press button and it will not lock down, will display man opp but will not move axis, press and hold for 3-4 seconds to energize the 2 relays before the axis will move.

Phill

asto
15-04-2013, 07:34 PM
Asto,
Have you had a look at the interlock on the key/stop button I understand you turn the key to the right press button and it will not lock down, will display man opp but will not move axis, press and hold for 3-4 seconds to energize the 2 relays before the axis will move.

Phill

Hi phill05 and thanks for your participation and helping effort.
Well I just followed your suggestion but there was no difference. I need to tell you though that all the operating electronics and hardware are not tightened/screwed on the lathe. It is all on the bench where I will instantly notice when the change comes. I believe might have been a wire left unconnected or disconnected I am not sure which one is the right word here. Please correct me. For example I have omitted signal wires coming from the perforated speedometer disc, those coming from turret indexing sensor, as well as those directed to power chuck electropneumatic solenoid, those directed to Parajust VFD pot and stop/restart inputs.
When the machine's X-axis was losing direction 2 weeks ago, searching for faulty wire connections I found that the X-stepper was not wired correctly. When I restored this, both axes worked perfectly responding to sudden commands. Both motors now retain good holding torque.
Last night I replaced the 30 year old stepper with the one seen in the attached image...With the StepSyn steppers this Orac worked non stop for 5 years 4 to 6 hours a day...

regards

Asto876787688769

asto
23-04-2013, 10:21 PM
Asto,
Have you had a look at the interlock on the key/stop button I understand you turn the key to the right press button and it will not lock down, will display man opp but will not move axis, press and hold for 3-4 seconds to energize the 2 relays before the axis will move.

Phill

Hi Phillo5!
Do you know where these relays are located and of what kind they are.Latching relays/normally open maybe? Energized by 5-volt pulses?
Cause in the keyboard matrix there is one 5-volt line.