I would be happy to help others build this printer, but it is not an easy one to build, let that be very clear.
In the past we've built several other printer, a few Prusa i2, a few Prusa i3 also MK2(even a 200×300) a CoreXY, Skeleton, and a few others. They all were rather easy to assemble, except for the very first one of course…
In my Ulti-Printer I abandoned all LMUU linear bearings. I made my own bearings. These 'linear'bearings are made of separate (48!)ball bearings in total. I can adjust these bearings so all play can be ruled out completely. And of course these bearings are all absolute maintenance free.
To give you an idea of the complexity of these printed parts here's the XY-carriage in transparancy. Printing these parts containing all these ball bearings : there's no room for error at all. The holes for the ball bearing's axis must be printed perfectly. If not the axis won't fit, or the bearings are not at the correct angle, or there's to much play, or on the contrary the X an Y axis won't fit in that part at all. To be clear I had to make a lot of testprints myself before correct parts were usable. But in the end it payed of, I print perfect perimeters, except for a few minor details no issues at all to be seen. Higher up in this thread is a pictures of apart printed with that Ulti-Printer.
This printer has :
No LMUU bearings.
Silicone heatbed 200×300
Print height 230mm
Fast interchangeable hotend system.
1.75mm filament direct drive.
TMC2100 silent stepper driver.
I use the full 200×300 bed surface.
This printer total cost : 470€ (all depends of course where things are bought.)