Hi GoCe - Use proper round cars and matching round rail. Not commercial tubing, Won't work. Linear rail is hardened and ground to a specification. The car balls will gall the unhardened steel or aluminium tube. Peter
what you think about SBR16UU linear bearing block on steel/aluminum tubing, can it work??
Of course it will 'work'.
Those hardened steel balls will work lovely grooves into the soft steel or aluminium tubes. After the first couple of passes there will be no more drag at all. Could be a little slop and rattle of course.
Cheers
Roger
PS: the above 'approval' is not meant to be taken seriously.