X Axis Ballscrew 8mm x 2.5pitch???

[TimPower]

Hi there,
I took off the cross slide on our Novaturn to find a very small ballscrew inside. It appears to be 8mm x 2.5 pitch whereas all the documentation I have read, and all the drawings I have seen say that the Novaturn should have a 16x5 ballscrew.
Does anyone know why this would be? Were the ballscrews upgraded to something stronger post 1997.

Best regards,

Tim Power.

Edit: Pic added. It has the correct bearings and 12mm journal you'd expect on a 16mm ballscrew but for some reason it is then coupled to an 8mm screw.

[Steve]

I suspect someone has retrofitted this.

This is not a factory fitted screw.

[TimPower]

Cheers Steve,
It's very odd why someone would go down this route. It was bought before my time here so it's possible the guy who ordered it got it from a refitter. However it may throw a light on the problem we had with this machine, i.e. stalling on the X axis. I've ordered a new ballscrew and anti backlash nut so hopefully with a bit of turning and milling this will get us up and running again.

Thanks for the reply.

Tim.