Marchant Dice router no thrust bearings?

[gavztheouch]

I have been aware of the fact that there are no thrust bearings or any sort of proper ballscrew mounts on my marchant dice router. Up until now it ain't been much of an issue as I was cutting soft mdf and plastic at slow speed. Last week I had a job to cut some birch and I noticed the accuracy to a hit. All my dimensions were consitently off by 0.4mm or so, regardless of the length of the dimension, this sound like backlash. The couplers are tight so I reckon it is due to the fact that the ballscrew does not have a thrust bearing and the design realise completly on the stepper motor resisting the force on the ballscrew. The stepper won't do this as I was expecting, so I think I will prob need some proper mounts.

Has anyone else got a marchant dice A4 sized router with the same prob?

Here is a pic of the current setup. x,y and z are all indentical.

The x axis ballscrew end arrived bent and the coupler had a lot of runout in the machining, so much so that it wiggles the stepper motor a lot as the axis is moved.