This is a Geeetech i3 Z axis modification. Mine is the plywood version, so it may not be good for acrilic or other versions.
The final Z printing area depends on the extruder throat length, I have a 50mm throat and I reach 235mm; the original Geeetech throat is 38mm long, so the printing area will be about 245mm.
There are some parts to extend the top of the printer, without major modifications of the frame, there will be the need to drill just two 3mm holes. The other parts are the step motors supports, fitting in original Geeetech frame junctions, plus you will need to drill four 3mm holes. All parts and rods are Geeetech i3 standard parts.

In total, all the extra parts you need are six M3 bolts with nuts and washers.
In the assembly the parts have the position and orientation to fit Geeetech frame.
The left side motor support will cover half of the electronics cooling fan original location. In my case the fan do not live there so it is not a problem, but if your fan lives there, you may need to move it.

mini heatsink
Mini heatsink

extruder heatsink mk10
Heatsink MK10

heatsink washer
Heatsink washer

extruder throat mk8
Extruder throat MK8

4mm teflon tube connector
Teflon tube connector 4mm

30mm fan
30x30 cooling fan

40mm fan
40x40 cooling fan

GT2 belt
GT2 belt

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