Parts & Components

SG90 and MG996R servos

The two PWM servos most first robots are built on: the 9 g plastic-geared SG90 (about 1.8 kg·cm claimed) and the 55 g metal-geared MG996R (9–11 kg·cm claimed). Cheap, available anywhere, documented everywhere — and so are inflated specs and counterfeits. They are the parts you can buy ten of without wincing, and the first parts that burn you.

Blueprints

Blueprints · B

Spot Micro: a few-hundred-dollar quadruped, and exactly where its ceiling is

Twelve servos, one driver board, one Raspberry Pi. The quadruped most people actually finish — and the one whose 'no f…

Spot Micro quadruped · SG90 and MG996R servos · 3D printing and materials · 2026-09-28

Build one

Build one · B

Build a servo quadruped: the Spot Micro route to an MVP

The legged route most people actually finish. The MVP is not smooth walking; it is stable standing and a straight-line…

Spot Micro quadruped · SG90 and MG996R servos · IMU orientation sensors · 3D printing and materials · 2026-09-28

Hardware

Hardware · B

SG90 and MG996R: the two servos most often bought wrong

The default actuation of first robots. Cheap is their virtue; inflated specs are their norm. This entry takes the numb…

SG90 and MG996R servos · IMU orientation sensors · 2026-09-28

Claim Check

Claim Check · A

'This servo does 20 kg·cm': can the datasheet figure be a design figure?

The design move: size by a third of the claimed figure, and use the peak only to sanity-check transients. Add a column…

SG90 and MG996R servos · Feetech STS series servos · Robstride joint motors · 2026-09-28