# Parts by milestone

> For agents: start with the [agent guide](https://parol6.build/llms.txt). Every page is Markdown by default; add `Accept: text/html` for HTML.

**Stub.** This page gathers the Parts section of each milestone so the whole bench is on one page. The milestone pages hold the full lists and their citations; open them before buying or printing anything.

## M1. Bench it

The control board with six TMC5160 drivers, the GX16 power connector and its XT30 lead, the E-stop, one limit switch, one NEMA 17 motor loose on the bench, and a 24 V DC supply of at least 5 A. Full list: [M1 parts](/lore/m1-bench-it#parts).

[Print timelapses](/lore/timelapses): [Plate 0: wrist and E-stop box](/lore/timelapses#timelapse-plate0-wrist-estop).

## M2. One joint end to end

The printed wrist part, the EG 10:1 planetary gearbox, Stepper 1, Sensor 1, the AXK3552 thrust bearing, the shaft coupler and the M3 homing screw, plus an ST-Link and the programming adapter. Full list: [M2 parts](/lore/m2-one-joint#parts).

[Print timelapses](/lore/timelapses): [Plate 0: wrist and E-stop box](/lore/timelapses#timelapse-plate0-wrist-estop).

## M3. The whole arm moves

Everything else in the official [bill of materials](https://docs.source-robotics.com/PAROL-docs/1.1/build/bill-of-materials/): the two EG 20:1 gearboxes, the remaining motors, the belts, bearings and couplers, and the remaining limit switches and inductive sensors. Full list: [M3 parts](/lore/m3-whole-arm#parts).

[Print timelapses](/lore/timelapses): [Plate 1: J5 forearm part and lids](/lore/timelapses#timelapse-plate1-forearm-j5), [Plate 3: pulleys](/lore/timelapses#timelapse-plate3-pulleys).

## M4. Pick and place

One gripper, chosen at the start of the milestone from the official [end effectors](https://docs.source-robotics.com/PAROL-docs/1.1/end-effectors/), or a printed gripper of our own design. Full list: [M4 parts](/lore/m4-pick-and-place#parts).

## M5. Touch the skiff

**Our design.** The skiff, a rigid shared base plate, and a knob-turning end effector. Full list: [M5 parts](/lore/m5-touch-the-skiff#parts).

## M6. Patch a cable

**Our design.** A cable-holding gripper, patch cables, and a cable rack or nest. Full list: [M6 parts](/lore/m6-patch-a-cable#parts).

## M7. Play it

**Our design.** The M5 and M6 rig, a clock source, and a sequencer script on the PC. Full list: [M7 parts](/lore/m7-play-it#parts).

## Terms

- **bill of materials**: the official parts list for the arm, in sections for screws and nuts, gearboxes, motors, belts, pulleys, shaft couplers, bearings and electronics, with quantities and buying links for most items ([Bill of materials](https://docs.source-robotics.com/PAROL-docs/1.1/build/bill-of-materials/)).

## Sources

1. [Bill of materials, PAROL6 docs 1.1](https://docs.source-robotics.com/PAROL-docs/1.1/build/bill-of-materials/)
   Source Robotics. The official parts list for the whole arm. Accessed 2026-11-07.

2. [PAROL6 building instructions](https://docs.source-robotics.com/PAROL-docs/1.1/assets/pdf/PAROL6_building_instructions.pdf)
   Source Robotics. The per-assembly parts the wrist pages list, pages 21 to 23 and 97 to 98. Accessed 2026-11-07.

3. [Drives, ratios and resolution, PAROL6 docs 1.1](https://docs.source-robotics.com/PAROL-docs/1.1/03-technical-data/drives-and-ratios/)
   Source Robotics. The motor and gearbox for each joint. Accessed 2026-11-07.

4. [End effectors, PAROL6 docs 1.1](https://docs.source-robotics.com/PAROL-docs/1.1/end-effectors/)
   Source Robotics. The gripper choices for M4. Accessed 2026-11-07.

## Lore on this page

- [The PAROL6 milestones](/lore/milestones)
- [M1. Bench it: power, one motor, a safe stop](/lore/m1-bench-it)
- [M3. The whole arm moves](/lore/m3-whole-arm)
- [M2. One joint end to end: the wrist and joint 6](/lore/m2-one-joint)
- [The skiff target](/lore/skiff-target)

## What links here

- Agent guide → Joel builds a PAROL6 robot arm, one sourced and filmed milestone at a time. → [Read page](https://parol6.build/llms.txt)

- Change log → What changed in the files served here, newest first. → [Read page](https://parol6.build/log)

- Full agent guide → Joel builds a PAROL6 robot arm, one sourced and filmed milestone at a time. → [Read page](https://parol6.build/llms-full.txt)

- PAROL6 build → Joel builds a PAROL6 robot arm, one sourced and filmed milestone at a time. → [Read page](https://parol6.build/)

- PAROL6 wiki | PAROL6 build → The PAROL6 build wiki: the milestones, their videos and the official sources behind them. → [Read page](https://parol6.build/lore)

- Source change history (log.md) → The generated change log as Markdown. → [Read page](https://parol6.build/log.md)