A4 1.0 Robot Arm User Manual
How to Make a 3D Printed Robot Arm
Overview
The A4 is a 3D-printable robot arm with 4 axes of motion plus a 1 degree of freedom gripper. It can be used to pick and place objects, pour liquids, clean surfaces, and more.
This manual is written assuming you may be building the A4 from raw materials. For example, it includes instructions for making the motor cables using rectangular connectors and crimp pins. If you bought these cables from Sage Robots, you can simply skip those steps.
Parts List
Base
| Description |
Quantity |
Part Number |
| A4 Riser |
1 |
A4-RISER-1.0 |
| A4 PCB Bracket |
1 |
A4-PCB-BRACKET-1.0 |
| M4x25 screw |
8 |
SCREW-M4-25 |
| M4 nylon-insert locknut |
4 |
NUT-M4-NYLOCK |
| M4 nut |
4 |
NUT-M4 |
| Mega microcontroller |
1 |
CTRL-MEGA |
| M2.5x11 standoff |
4 |
STANDOFF-M2.5-11-NYLON |
| M2.5 nylon nut |
4 |
NUT-M2.5-NYLON |
| M2.5x6 nylon screw |
4 |
SCREW-M2.5-6-NYLON |
| A4 PCBA |
1 |
A4-PCBA |
Joint 0
| Description |
Quantity |
Part Number |
| J0 Base |
1 |
A4-J0-BASE-1.0 |
| M2 heat-set insert |
2 |
HEAT-SET-M2 |
| NEMA 17 27:1 Geared Stepper Motor |
1 |
MOTOR-STEP-17-27.1-1000 |
| M3x8 button head screw |
4 |
SCREW-M3-8-BH |
| M4x16 screw |
4 |
SCREW-M4-16 |
| M4 nylon-insert locknut |
4 |
NUT-M4-NYLOCK |
| 6mm clamping hub |
1 |
HUB-6 |
| Thrust bearing, 65mm ID 90mm OD |
1 |
THRUST-65-90 |
| J0 plate |
1 |
A4-J0-PLATE-1.0 |
| M4 heat-set insert |
8 |
HEAT-SET-M4 |
| M4x10 set screw |
4 |
SCREW-M4-10-SET |
| M4 Nut |
4 |
NUT-M4 |
| #6x1/2 button head screw |
4 |
SCREW-6-1-2 |
| Home switch A |
1 |
PCBA-HOME-A-1.0 |
| M2x5 screw |
2 |
SCREW-M2-5 |
Joint 1
| Description |
Quantity |
Part Number |
| J1 base |
1 |
A4-J1-BASE-1.0 |
| M2 heat-set insert |
2 |
HEAT-SET-M2 |
| M4x10 Screw |
4 |
SCREW-M4-10 |
| NEMA 17 27:1 Geared Stepper Motor |
1 |
MOTOR-STEP-17-27.1-1000 |
| M3x8 button head screw |
4 |
SCREW-M3-8-BH |
| 6mm clamping hub |
1 |
HUB-6 |
| Thrust bearing, 60mm OD 40mm ID |
1 |
THRUST-40-60 |
| J1 Plate |
1 |
A4-J1-PLATE-1.0 |
| #6x1/2 button head screw |
4 |
SCREW-6-1-2 |
| M4 heat-set insert |
6 |
HEAT-SET-M4 |
| M4x10 set screw |
4 |
SCREW-M4-10-SET |
| M4 Nut |
4 |
NUT-M4 |
| Home switch A |
1 |
PCBA-HOME-A-1.0 |
| M2x5 screw |
2 |
SCREW-M2-5 |
Joint 2
| Description |
Quantity |
Part Number |
| Humerus |
1 |
A4-HUMERUS-1.0 |
| M4x6 screw |
2 |
SCREW-M4-6 |
| J2 Motor Bracket |
1 |
A4-J2-MOTOR-BRACKET-1.0 |
| M4x25 screw |
2 |
SCREW-M4-25 |
| M4 oversize washer |
2 |
WASHER-M4-O |
| M4 nylon-insert locknut |
7 |
NUT-M4-NYLOCK |
| NEMA 17 27:1 Geared Stepper Motor |
1 |
MOTOR-STEP-17-27.1-1000 |
| M3x8 button head screw |
4 |
SCREW-M3-8-BH |
| 15 tooth XL pulley |
2 |
PULLEY-XL-15 |
| J2 Tensioner |
1 |
A4-J2-TENSIONER-1.0 |
| M4x12 flathead screw |
2 |
SCREW-M4-12-F |
| M4-40 screw |
1 |
SCREW-M4-40 |
| J2 Base |
1 |
A4-J2-BASE-1.0 |
| M4x12 screw |
2 |
SCREW-M4-12 |
| M2 heat-set insert |
2 |
HEAT-SET-M2 |
| J2 shaft |
1 |
A4-J2-SHAFT-1.0 |
| M6 washer |
2 |
WASHER-M6 |
| Ball bearing, 6mm ID 19mm OD |
1 |
BALL-6-19-6 |
| 6mm clamping hub |
1 |
HUB-6 |
| Thrust bearing, 47mm OD 30mm ID |
1 |
THRUST-30-47 |
| J2 Plate |
1 |
A4-J2-PLATE-1.0 |
| #6x3/8 button head screw |
4 |
SCREW-6-3-8 |
| M4 heat-set insert |
6 |
HEAT-SET-M4 |
| M4x12 set screw |
4 |
SCREW-M4-12-SET |
| M4 Nut |
4 |
NUT-M4 |
| Home switch B |
1 |
PCBA-HOME-B-1.0 |
| M2x5 screw |
2 |
SCREW-M2-5 |
Joint 3
| Description |
Quantity |
Part Number |
| Radius |
1 |
A4-RADIUS-1.0 |
| M4x6 screw |
2 |
SCREW-M4-6 |
| J3 Base |
1 |
A4-J3-BASE-1.0 |
| M2 heat-set insert |
2 |
HEAT-SET-M2 |
| M4x12 screw |
2 |
SCREW-M4-12 |
| M4 nylon-insert locknut |
2 |
NUT-M4-NYLOCK |
| NEMA 11 27:1 geared stepper motor |
1 |
MOTOR-STEP-11-27.1-300 |
| M3x8 button head screw |
4 |
SCREW-M3-8-BH |
| 6mm clamping hub |
1 |
HUB-6 |
| Home switch A |
1 |
PCBA-HOME-A-1.0 |
| M2x5 screw |
2 |
SCREW-M2-5 |
Gripper
| Description |
Quantity |
Part Number |
| M4 heat-set insert |
2 |
HEAT-SET-M4 |
| #6x3/8 button head screw |
7 |
SCREW-6-3-8 |
| DC motor, 12V 26RPM 4.6Nm |
1 |
MOTOR-DC-12V-26RPM-4.6NM |
| M2.5x6 screw |
2 |
SCREW-M2.5-6 |
| 4mm clamping hub |
1 |
HUB-4 |
| M4x16 button head screw |
1 |
SCREW-M4-16-BH |
| M4 nylon-insert locknut |
1 |
NUT-M4-NYLOCK |
| Home switch B |
1 |
PCBA-HOME-B-1.0 |
| M2x5 screw |
2 |
SCREW-M2-5 |
| Fixed Gripper |
1 |
A4-GRIPPER-FIXED-1.0 |
| Gripper motor bracket |
1 |
A4-GRIPPER-MOTOR-BRACKET |
| Mobile gripper |
1 |
A4-GRIPPER-MOBILE-1.0 |
| Gripper fingertip |
1 |
A4-GRIPPER-FINGERTIP-1.0 |