thanks to all, the good news is that I have been offered help by HS93 member on here, I will be taking the lathe to him, and he is going to check it out, inspect all my bits and pieces, and watch how I do things! then put me right, so watch this space for the embarrasing outcome, I bet its something really obvious!!
I do think though, even in my novice status, the required precision is fine on the headstock end, but sadly lacking on the tailstock end, unless you are an experienced machinist that can sort these things out, and these lathes I would suspect are starter lathes to people like me, so its a bit of a vicious circle, but a learning curve which is good, it then amazes me how anybody gets any accuracy from the ancient pre war lathes for sale on ebay, thank goodness I didnt end up with one of them!
Paul