orac headstock out of adjustment

[Bert]

hi to all

i am in process of sorting out an orac

whilst getting to know how machine works i have been doing some basic turning

when cutting along the z axis the work piece diameter reduces by approx 2 thou over 3/4 "

were should i start to rectify this

cheers bert

[Denford Admin]

Have you got access to some ground bar and a Dial Test Indicator (ie, clock) ?
These will make aligning it much easier than running cutting tests every time.
Are you using a tailstock ?

[Bert]

hi admin

i was cutting some black nylon at about 5 mm

it might have been deflection

have got imp dti on mag mount

re tried with some hex brass with aprox 3" from chuck with out tail stock ( unable to garantee accuracy of tail stock ) this showed 2 thou other 2"

before i go further i must get some ground bar

have spotted adjusment location on back of headstock i will not touch this untill i realy have to

if i do have to adjust what is correct procedeure for both head and tail

cheers bert

[Denford Admin]

I'll have a look around for some instructions (maybe there anything in the Orac or novaturn manuals in the download section ?)

Some advise I've just been given though:
The chuck OD is probably not qualified, so don't clock that and use it as a reference - only a test bar held in the chuck matters.

[frogeye]

Hi Admin,

Did you ever find set-up instructions? I've just refitted an ORAC with modern electronics and MACH3... but I have the same tapering cut problem. I've not looked into it any further, but some guidance would be very useful.
TIA,
Paul

[Denford Admin]

Hi - sorry but I've asked around and it would seem that kind of machine setup has never been documented - its the sort of thing that gets done when the machine is built, and should never need adjusting (unless of course you crash the machine)

With the Orac the Z axis was setup parallel first, then the X was also thrown so that it ran square to the Z.
I'd hope that your problem will just need the Z resetting by throwing the headstock:
If you don't have a ground test bar, then you could try this procedure:
do a long cut on a test piece,
measure the taper,
put the clock on the far end of the test piece,
loosen the 4 headstock screws slightly,
tap the headstock around until the clock moves half of the taper amount - which way to go will depend whether its cutting big or small at the end.,
tighten and try the test cut again..

you may also find that your centreline will have shifted, so re-check your offsets.

HTH

[frogeye]

Thanks Admin,

I'm just in the process of putting the PC and new electronics back into the cabinet... I'll have a good look at this when I can run the spindle again
Cheers