JST JGD-125C Water Cooled Spindle
Overview
A 5.5kW / 6kW Chinese water cooled spindle with an ER25 collet chuck. It is marketed for stone engraving rather than CNC routing.
Replacement Parts
Angular Contact Bearings
7007C T 2RZ HQ1 P4 DBL Z3X 131018044B
Deep Groove Bearings
SKF E2 6004-2Z/C3 15 260 K
Bottom Locknut
Doubles as a dust shield:
- 56.7mm OD
- 5.1mm thick (dust shield portion)
- 4x 3.5mm holes 3mm deep on a 44mm diameter circle
Top Locknut
- 32mm overall OD
- 10mm thick
- M20x1.0mm threads on the ID
- 26mm OD / 22mm ID rim for bearing's inner shield
- 1.8mm clearance around the rim for the bearing's shield, as well as a shoulder with no threads on the inside
O-rings
Must fit within a 10mm OD 1mm deep recess with a 6mm ID hole for water to pass through. Maybe one of these?:
- Square-Profile Oil-Resistant Buna-N O-Ring, 1.5 mm Wide, 7 mm ID | McMaster-Carr
- Square-Profile Oil-Resistant Buna-N O-Ring, 2 mm Wide, 6 mm ID | McMaster-Carr
- Oil-Resistant Buna-N O-Ring, 1.5 mm Wide, 6.5 mm ID | McMaster-Carr
- Oil-Resistant Buna-N O-Ring, 1.78 mm Wide, 6.35 mm ID | McMaster-Carr
- Oil-Resistant Buna-N O-Ring, 1.8 mm Wide, 6 mm ID | McMaster-Carr
- Oil-Resistant Buna-N O-Ring, 2 mm Wide, 6 mm ID | McMaster-Carr
Fasteners
Dust Shield
For holding the dust shield to the lower angular contact bearing retaining ring:
4x Alloy Steel Socket Head Screw, Black-Oxide, M4 x 0.7 mm Thread, 8 mm Long | McMaster-Carr
Lower Angular Contact Bearing Retaining Ring
For holding the lower angular contact bearing retaining ring to the bearing housing:
4x Alloy Steel Socket Head Screw, Black-Oxide, M4 x 0.7 mm Thread, 12 mm Long | McMaster-Carr
There are two M4-0.7 tapped holes 9.5mm deep for jacking the ring away from the housing, we used 25mm long screws.
Bearing Housing
Grub screws w/ teflon tape for sealing some water ports (manufacturing process side effect?):
2x Alloy Steel Cone-Point Set Screw, M6 x 1 mm Thread, 8 mm Long | McMaster-Carr
TODO verify the following:
For holding the bearing housing to the main spindle body:
6x Alloy Steel Socket Head Screw, Black-Oxide, M5 x 0.8 mm Thread, 16 mm Long | McMaster-Carr
Upper Angular Contact Bearing Retaining Ring
For holding the upper angular contact bearing retaining ring onto the housing:
4x Alloy Steel Socket Head Screw, Black-Oxide, M5 x 0.8 mm Thread, 12 mm Long | McMaster-Carr
Upper Rotor Bore Cover
For holding a lid over the upper part of the rotor to protect the floating bearings from contamination:
3x Alloy Steel Socket Head Screw, Black-Oxide, M4 x 0.7 mm Thread, 12 mm Long | McMaster-Carr
Spindle Top Cap
For holding the water inlet/electrical inlet cap onto the main spindle body:
TODO military connector screws?