Advanced Assembly

Combine motors, printed parts, and PCBs inside an assembly.device. These examples show how named mounting faces connect a NEMA17 to a printed bracket, then place its controller on the same base.

Start with the index.tsx tab to see the assembly connections. The other tabs contain the complete geometry and controller components; the editor button opens all the files together.

Mount a motor to a printed bracket

The bracket has a base, an upright with a shaft opening, and two supporting ribs. Its four motor holes are 3.2 mm in diameter on the NEMA17's 31 mm square pattern. A 23 mm opening clears the motor's 22 mm pilot.

mountedTo="BRACKET.motor" selects the bracket's named attachment face. mountFace="frontface" selects the motor's shaft-side body face. Core mates those two faces, positioning and orienting the motor without manual CAD offsets.

import { assembly } from "tscircuit"
import { MotorBracket } from "./motor-bracket"

export default () => (
  <assembly.device>
    <assembly.printedpart name="BRACKET" jscad={<MotorBracket />} />
    <assembly.motor
      name="MOTOR"
      standard="nema17"
      mountedTo="BRACKET.motor"
      mountFace="frontface"
    />
  </assembly.device>
)

The motor-bracket.tsx tab defines the attachment face alongside its geometry:

<jscad.translate offset={[0, 0, 32]}>
  <jscad.rotate angles={[0, -Math.PI / 2, 0]}>
    <jscad.rectangle name="motor" size={[42, 42]} reference />
  </jscad.rotate>
</jscad.translate>

This reference is centered 32 mm above the base's underside and faces −X. Mating the motor's frontface to it points the shaft along +X, through the upright. reference rectangles describe attachment frames; they do not add material to the printed part.

Face origins coincide, outward normals oppose, and the faces' in-plane X directions align. Rotating the reference therefore controls the motor's rotation around its shaft as well as its shaft direction. Omit shaftFacingDirection when using mountedTo and mountFace.

Add a controller to the same base

The bracket also defines a controller face at the tips of four posts. Mount a board to that face, using the same hole coordinates for the posts and PCB.

import { assembly } from "tscircuit"
import { MotorBracket } from "./motor-bracket"
import { MotorController } from "./motor-controller"

export default () => (
  <assembly.device>
    <assembly.printedpart name="BRACKET" jscad={<MotorBracket />} />
    <assembly.motor
      name="MOTOR"
      standard="nema17"
      mountedTo="BRACKET.motor"
      mountFace="frontface"
    />
    <MotorController
      mountedTo="BRACKET.controller"
      pcbX={-10}
      pcbY={50}
    />
  </assembly.device>
)

MotorController forwards its mounting props to <board>. The controller face is at [-10, 50, 14] in the bracket's local coordinates; the board uses pcbX={-10} and pcbY={50} to preserve that layout. Its four 3.2 mm holes use the same 64 × 24 mm pattern as the posts. The post tips are 14 mm above the base's underside, including the 5 mm base plate.

Mounting keeps the PCB in the XY plane at Z = 0. Core moves the connected bracket and motor around it: in this example, the bracket's underside moves to Z = −14.8 mm so the posts touch the bottom of the 1.6 mm PCB. No manual Z offset is needed in the assembly code.

The four-pin J_MOTOR header reserves a connection for the motor's two windings. The driver package and headers demonstrate board placement; this example has no routed driver circuit or cable connection. Replace them with your controller circuitry when adapting the assembly.

Adjust the mounting

Change	How
Separate a motor from its bracket	Add mountGap="2mm" to assembly.motor. The gap follows the target face's outward normal.
Use the rear of the motor	Set mountFace="backface" and provide a bracket with the appropriate rear mounting geometry.
Change the motor's direction or rotation around the shaft	Rotate the bracket's reference rectangle. JSCAD angles are in radians.
Raise the controller	Move both the post tips and the controller reference to the new height.
Put a spacer between a motor and a PCB	See the motor–spacer–board example.

frontface is the shaft-side body plane, excluding the pilot and shaft. backface is the body plane opposite the shaft. Face mounting does not generate screw holes or check collisions; model the required holes and clearances in the printed part.

References resolve within the nearest assembly.device, and declaration order does not matter. A connected assembly can have one PCB anchor. Missing or ambiguous targets, cycles, and a PCB mounted to a tilted face report errors. For assemblies containing a face-mounted motor, author rotation in the reference geometry rather than using board mountRotation or mountRotationAnchor.

These examples require @tscircuit/core 0.0.2085 or later, with @tscircuit/props 0.0.687 or later. For all available props, see assembly.motor and assembly.printedpart.