MK8 Extruder for Makerbot Replicator Clone

This my new extruder for MK8 Gear.
Gear have OD 9mm against OD 12mm in MK7, that use in Replicator, FF, CTC.
Its needing for new Alu Cooling Block (Bar) that hold hotends and motors.
Because it will be 37mm between holes/nozzles against 33mm in original or 34mm for Flashforge
9mm Gear has strong extrusion in theory (34% power up).

v 4.0
Redesign mount block, like FlashForge.

v 2.0
Add bearning for imbus screw

Parts for assembly :
2x imbus scew 3x16 (or 3x14)
2x flat-head screw 3x6
2x MK8 Gear (OD 9mm!)
1x new Aluminium Bar (Block) with 37mm between nozzle.


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EXTRUDER IN PROCESS.
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bearing Used for this extruder is 623Z, 623ZZ (ID:3*OD:10*TH:4)

https://ru.aliexpress.com/item/623Z-ABEC-5-Chrome-steel-bearings-10pcs-metal-Sealed-Miniature-Mini-Bearing-free-shipping-623/32695350387.html

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Setting for MK8 gear:
From reprap:
Real-life measured data (tested with 1.7mm filament):

Effective diameter: 6.7mm
Effective circumference : 21mm
Steps p