I own a Techzone Huxley that I bought way back in ~2010, back when the only options for complete 3D printer kits were it or the original wood-framed Makerbot.
I realized pretty quickly that its a complete piece of crap. As soon as I would accomplish one thing, another thing would break, and Techzone had some of the worst customer service I'd ever seen. After a few months of this, the board stopped working, I got burnt out, and set it aside.
Fast forward a few years, and I bought a RAMBo board to replace the original. But around that time I got swamped at work, and didn't have time to mess with it.
Fast forward to now, and I've committed myself to making this POS work.
1) My first issue is the Z-axis 360 end.
In the following picture, I've marked two points - width A, and width B.
Width A is the distance between the threaded rod and the roller bearing track.
Width B is the distance between the threaded rod and the smooth rod at the base of the frame.
These distances should be equal.
Here's the problem: those distances are not equal - A is shorter than B - and there is no legitimate way of adjusting them.
The original instructions suggested adjusting the number of spacer washers between the bearings marked by the arrow and the plastic frame. But that makes the smooth rod track way too wide and allows a fair amount of both x and y-axis play, which would certainly reduce print quality.
Was there ever an improvement to this design to allow for better adjustability?
Problem solved. I Dremeled out the slot for the smooth bar on the bottom bracket - on the side facing the print carriage - and shimmed the other side with a piece of plastic. Its a really inelegant way of fixing the problem - I'd have preferred a non-destructive, reversible method of adjustable - but hey, it worked. I can't really complain.
Next step is to fab aluminum brackets for the new mechanical endstops, update my RAMBo board, and buy a new hotend. The original probably still works, but I'm sure they've come an enormously long way over the past 7 years. I'm looking at the E3Dv6, and probably 1.5mm although that might mean I'd need to fuss with the original extruder. I'll have to check it when I get home from work.