Thanks for the encouragement, folks!
Lazylathe - some people use a pinchuck for these closed enders, but they can be hard to come by, so I went cheap and used a jam chuck (using 3/8 roundstock glued into a piece of scrap hardwood, turned to the inside diameter of the brass sleeve) fitted into my drill chuck.
Snyiper - I think you're right. If I could find a nice piece of neutral cooured paper (eg grey), that would work better. White is too light, throws off the balance.
Cheers
Ken