RBK Motor Bracket for BK12 & BK15 Ball Screw Supports — NEMA 23 / 34

The RBK motor bracket holds the stepper motor in line with the ball screw, mounted right above the BK support. The cast body is rigid and damps vibration, with machined seats so the motor lands square the first time — no improvised plate that throws off alignment and wears the screw.

Where it is used

On CNC router, mill or plasma axes where the motor couples straight onto the end of the ball screw. It replaces the usual bent bracket and spacer stack with one finished casting.

What is included

The cast bracket and the lock nut. Ball screw, BK support and coupling are not included.

Choose your model

• RBK12-57 — BK12 support, Ø12 mm screw, NEMA 23 (57 mm) motor. Shaft centre height 25 mm, 60×60 mm motor flange, 4×M4 on a Ø47.1 mm circle, Ø38.1 mm pilot. Body 46 mm wide, 94 mm long.
• RBK15-57 — BK15 support, Ø15 mm screw, NEMA 23 (57 mm) motor. Shaft centre height 28 mm, 4×M4 on a Ø47.1 mm circle, Ø38.1 mm pilot. Body 58 mm wide, 104 mm long.
• RBK15-86 — BK15 support, Ø15 mm screw, NEMA 34 (86 mm) motor. Shaft centre height 28 mm, 86×86 mm flange, 4×M6 on a Ø69.6 mm circle, Ø73 mm pilot. Body 58 mm wide, 114 mm long.

Pair it with a BF12 or BF15 support at the far end of the screw. Manufacturer codes are SSX12-57, SSX15-57 and SSX15-86.