Mon 04 Jun , 2012 11:29 am
Forum: Orac
Replies: 1
Views: 4504
Jump to post

Re: help to repair my orac

Hi, I have just converted my Orac to later 1983 electrics with a single cable to the later style keyboard, I have all the boards, cables etc that you would require along with manuals for your machine, if you are a student i will let you have what you require to get the machine up and running FOC ...
Sat 19 May , 2012 21:13 pm
Forum: Orac
Replies: 3
Views: 7034
Jump to post

Orac Threading

If anyboby is interested i have solved the problem with the screw cutting cycle dropping out.
i checked the speed and position sensors on the rear of the spindle, these were ok along with the signals getting through to the control boards, they where switching ok, 0v off 12v on then down to the 0v ...
Thu 26 Feb , 2009 11:48 am
Forum: Orac
Replies: 5
Views: 7848
Jump to post

ORAC Main spindle drawing

HI All
has anyone a drawing for an Orac head stock main spindle?
Measuring the existing one is ok but the nose taper is the problem !

i would like the dimentions as making backplates to match the spindle nose taper is causing poblems

any help would be appreciated

Chris
Thu 12 Feb , 2009 15:56 pm
Forum: Orac
Replies: 0
Views: 3564
Jump to post

Martin
Been a while, xmas hols and all that, not had time on my own in the shed but back on it now, my Orac is 1982, early version with no LED's on the PC board, have checked the signals at the terminals into and out of the board and they are Ok, next step is to trace them throuch the ribbon cable ...
Mon 19 Jan , 2009 15:23 pm
Forum: Orac
Replies: 5
Views: 7848
Jump to post

https://www.denfordata.com/downloads/dos ... RCAL-1.zip

https://www.denfordata.com/downloads/dos ... RCAL-2.zip

If you down load these drawings you will find the diagrams of you boards, check out numbers, 1714, 1804, 1849, and 1848
Tue 23 Dec , 2008 12:19 pm
Forum: Orac
Replies: 5
Views: 8112
Jump to post

Orac Screw cutting

Hi Martin.
The machine gets to the screw cutting page and then sets the spindle speed, moves the x axis to the start position and then the program ceases and gives you the manual X,Y axis position screen, the only way to recover is to press the program stop or reset and then reload the program ...
Sat 20 Dec , 2008 10:02 am
Forum: Orac
Replies: 5
Views: 7848
Jump to post

Orac Threading

Anyone got any ideas, my Orac drops out of the program at the start of a threading cycle.
I have checked the spindle speed and position sensors, they seemed ok but have replaced them anyway, they both switch ok and the signal is getting to the control board.

Help please

Chris
Fri 19 Dec , 2008 19:30 pm
Forum: Orac
Replies: 5
Views: 7848
Jump to post

Hmmm, 102v on pin 19 think you may be using the wrong ground to measure this, it should be between 0 and 10 volts, this is an isolated supply, the measured voltage will be well above 10 if you use the machine ground. the later boards where different to mine but the principal it the same, i will ...
Tue 16 Dec , 2008 19:16 pm
Forum: Orac
Replies: 5
Views: 8112
Jump to post

Thanks for the offer Keith but that overlay is no good to me, the overlay i require is the one on machine control.

Chris
Sat 13 Dec , 2008 7:47 am
Replies: 3
Views: 5638
Jump to post

Spindle Speed Problem

Hi, i have recently been working on my Orac with spindle speed problems so while its fresh i'll suggest some points to check.

On the PC1690 board, bottom one of the stack of three on the left side in the rear of the machine, check the voltage on connector TBF No19 (last terminal to the left of the ...
Wed 10 Dec , 2008 15:24 pm
Forum: Orac
Replies: 5
Views: 8112
Jump to post

Orac Boards

Hi Torleif
Recieved boards thank you, have now sorted all problems apart from thread cutting, pair of sensors on order should be here monday.
the Parametric dive board works fine, just needed fine tuning, it will run at 50 rpm no problem, somebody was over zelous with the boost pot.

I will do the ...
Sun 07 Dec , 2008 9:45 am
Replies: 17
Views: 19133
Jump to post

Spindle speed problem

Have just solved the problem with the zero volts on the speed control signal line, it was the 10volt Zener diode gone short on the PC 1623 speed control overide board, its the diode located between the power input connector and the signal line connector, the cause of it shorting not known but my ...
Sat 06 Dec , 2008 21:49 pm
Forum: Orac
Topic: orac
Replies: 2
Views: 5478
Jump to post

Spindle speed problem

If you have the same problem as me, it is the lack of voltage to set the speed, my orac has a similar problem, when you push the motor start button the relay drops in but the spindle will not turn, after some probing with a meter i found there is no speed signal voltage, as this is sitting at 0v the ...
Fri 05 Dec , 2008 21:03 pm
Forum: Orac
Topic: orac
Replies: 2
Views: 5478
Jump to post

Wanted ORAC Keyboard overlay

Does anyone have or knows where i can obtain an Orac keyboard overlay mine is worn through.
thanks

Chris
Fri 28 Nov , 2008 0:00 am
Replies: 3
Views: 5638
Jump to post

Yes, lots of vairables but have to run at fast speed to get the taper as x axis will not step at slow speed over length. has anybody got the original spec for operation ?
Wed 26 Nov , 2008 11:25 am
Forum: Orac
Replies: 6
Views: 10815
Jump to post

Thanks for all your input, i understand that a taper machined on a stepper driven machine will never be the perfect finish.
Entering the code, not a problem but while trying to run the job i found that if the feed rate was not high enough the machine would seperate the x and y, first traveling along ...
Tue 25 Nov , 2008 14:39 pm
Forum: Orac
Replies: 6
Views: 10815
Jump to post

ORAC taper turning

Hi all, new to this forum and CNC. Have recently purchased a 1983 ORAC, not working when i first tried to power it up but have since fixed the power supply probs, i have familierised myself with the programming and got my head round the loss of "0" position when powering up, easy just set the tool ...
Mon 24 Nov , 2008 13:50 pm
Forum: Orac
Replies: 6
Views: 10815
Jump to post

Hi Torleif

Not to worry, i have the pcb diagram so can work out type of relay and connections.
I would still like the the PC1600 and PC1623 if possible, My PC1601 is ok now, its probably the easiest board to repair, had a diode blown in the 24v bridge but all ok now, so that board may be of use to ...
Tue 04 Nov , 2008 19:04 pm
Replies: 17
Views: 19133
Jump to post

Torleif

Thanks, quick reply, email me, chris15@blueyonder.co.uk please and will give you address details and i would like yours so we can sort out postage

Thanks

Chris
Tue 04 Nov , 2008 15:16 pm
Replies: 17
Views: 19133
Jump to post