Thanks for the info Mark I'll have a look at that one. Instead of cheap skate bearings could I not use a single double row AC bearing, would I have to pre-tension it? Saying that I've skate bearings coming out of my ears as I'm planning on using them as the linear bearings on all my axis ;) The only problem I can see for me is making the bearing housing, I looked at our lathe this morning and the tooling is crap as it's only used to take the raised face off flanges etc, not sure when it last had a service either. Will get some Ali bar offcut and have a play I think. Hope it's ok as I was planning on machining my leadscrews on it!