Ive now had my printer for a couple of weeks and found a couple of issues. nothing big but as I find them , I'll make / download new parts
I noticed that one of my prints had a "ridge" part way down. A quick inspection revealed that the two 8mm rods at the back of the printer moved ever so slightly - on checking, the retaining holes varied in size from about 8.1 - 8.4 mm .
So I designed these replacements. and a "setting tool, for measuring and aligning the rods to the back wall.
The bottom ones are fiddly, but they are worth changing.
An added point is, that after changing them, the bed levelled in seconds.

Printed in Medium resolution ( 0.2mm) with PLA

Final fitting

I deliberately left the holes tight, then reamed them out with an 8mm drill - the holes were spot on after that ( with care)
Top ones were easy to change, but you will need to remove your bottom circuit board to gain access to one of the bottom ones, so unplug your machine!!!

The image shows one of the top ones in its final place.