SCARA Upper Arm Beam
The upper arm link of the 'NEMA17 Belt-Drive SCARA Drawing Arm' kit. It is a 177 x 50 x 22 mm ribbed beam with a 140 mm shoulder-to-elbow span. At the shoulder, an OD 44 pad bolts to the 60T hub with four M3 screws on a 34 mm PCD and has a 10 mm hole for the rod end. The elbow NEMA17 sits on a flat pad with 3.4 x 9.4 mm slots (31 mm square pattern) and a 23 x 29 mm pilot obround, so you can slide the motor ±3 mm to tension the GT2 belt. The elbow end has an OD 22 boss with an 8.3 mm bore for the 70 mm 8 mm rod, held by two M3 set screws in captured nuts, and an OD 11 thrust island underneath that bears on the 608 inner race.
robotics kit scara nema17