Projects / 3-DOF Plywood Arm
3-DOF Plywood Arm
Build a laser-cut 3-DOF robot arm from 3mm birch plywood with 3× SG90 or MG90 micro servos. Base yaw, shoulder pitch, and elbow pitch give a planar reach workspace—enough for forward kinematics and simple geometric IK.
$12 Robotics
Digital guide + cut files + BOM + code · Parts sourced separately · Ages 8–14 with adult help
DOF3 (yaw + 2 pitch)
Servos3× SG90/MG90
Structure3mm birch links
ControllerArduino Uno
Build time4–7 hours
Skill levelIntermediate
Pack contents
- Base, turret, shoulder upright, link1 (with elbow servo mount), link2, gripper stub SVGs
- FK demo → simple IK build guide
- First-principles: DOF, FK, geometric IK
- Joint-angle and IK target sketches
- Verified BOM (~$32–125 hardware)
Typical hardware cost
Default structure is laser-cut birch plywood with real fasteners and hobby electronics you can source—honest BOM, not mystery modules.
- ~$32–125 in typical parts (makerspace cut toward the low end; mail-order toward the high end)
- Digital pack price ≠ hardware
The $12 pack is the digital guide + cut files + BOM + lessons + code, plus printable Builder's Corner build journal pages. Hardware is sourced separately — see Where to get kit materials. Buy with Stripe is live below.
Questions? Email us at lance.haney@gmail.com.
Pricing
- Home / Personal license $12
- Classroom license $45 — 1 teacher, up to 30 studentsOne $45 Classroom license covers one group of up to 30 students. Each additional group needs another license.
- Build materials available at cost + 10% — email for a quote
Learning outcomes
- Explain 3 DOF vs a full 6-DOF industrial arm
- Assemble birch links with machine-screw revolute joints
- Map joint angles to end-effector pose (FK)
- Solve simple geometric IK for a planar 2-link arm