@brianhabby:
CHJ has it exactly. At least he has as per my machine. There's quite a lot of backlash on both slides, but it can be taken out to a certain extent (if I remember, the Fenner book tells you how, if not look it up on line at a couple of the websites shown on the sticky at the top of this Metalworking section). In practice though, because the backlash does creep back in again, I tend not to bother too much - just make sure when turning that you always turn the handle one way only - again Fenner or those sites describe.
It's not ideal I know, and wouldn't happen on a decent machine like a Myford or Boxford, or Colchester, but if you're sure you've got the gibs correctly adjusted (nice and tight, but so that you can still turn the handles through their whole range without any stiffness/binding) then personally I find it's easier to just work round it, as above. (Then when I get fed up with it I re-adjust to take most of the backlash out again - then carry on working again and wait until it gets annoying again).
@harbo:
Yup, I believe most but not all of these machines come from Sieg. In my case I THINK my machine (badged Einhell and coloured blue) comes from another manufacturer, also Chinese, called Red Dog or Red Bull or something like that. But I've also heard, again I'm not sure, that they have gone bust or at least just don't make lathes any more. But all the bits & pieces I've bought, which are mainly aimed at Sieg-sourced machines do fit mine - albeit sometimes with a small amount of modding.
AES