# UltraPlanetary Gearbox Assembly
## Gear Ratio Choices
The FTC Starter Kit comes with two of the UltraPlanetary Gearbox Kits with HD Hex Motors. This is an entry point into using the REV UltraPlanetary System. There are three UltraPlanetary Cartridges supporting seven different final gear reductions ranging from nominally 3:1 to 60:1. This allows for the right amount of torque for the application at hand. The motor provided already has the pinion gear pressed onto it making assembly of gearboxes easier.
When getting started with this drivetrain, it is recommended to use a nominal 20:1 Gear Ratio. This uses the UltraPlanetary 5:1 Cartridge and the UltraPlanetary 4:1 Cartridge. For more information on all gear ratio options, load ratings, and more, see the UltraPlanetary Gearbox User’s Manual on revrobotics.com.
## UltraPlanetary Assembly Parts Required
| **PART NUMBER** | **DESCRIPTION** | **QTY.** |
| ------------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------- | -------- |
| [REV-41-1600](https://www.revrobotics.com/rev-41-1600/) | ULTRAPLANETARY GEARBOX KIT & HD HEX MOTOR | 1 |
| [REV-41-1359](https://www.revrobotics.com/rev-41-1359/) | M3 X 8MM HEX CAP SCREWS | 4 |
| [REV-41-1360](https://www.revrobotics.com/rev-41-1360/) | M3 X 16MM HEX CAP SCREWS | 3 |
| [REV-41-1338](https://www.revrobotics.com/rev-41-1338/) | 15 TOOTH #25 SPROCKET | 1 |
| [REV-41-1846](https://www.revrobotics.com/rev-45-1883/) | MOTION PATTERN SPACER | 1 |
| | **ASSEMBLIES** | |
| [ASSEMBLY 1-4](/duo-build/ftc-starter-kit-chain-drivetrain/pre-loading-brackets.md#pre-loading-ultraplanetary-flat-mounting-bracket-steps) | PRE-LOADED ULTRAPLANETARY FLAT MOUNTING BRACKET | 1 |
| [ASSEMBLY 1-5](/duo-build/ftc-starter-kit-chain-drivetrain/pre-loading-brackets.md#pre-loading-ultraplanetary-bent-mounting-bracket-steps) | PRE-LOADED ULTRAPLANETARY BENT MOUNTING BRACKET | 1 |
**PARTS WITHIN THE ULTRAPLANETARY GEARBOX KIT**
| **PART NUMBER** | **DESCRIPTION** | **QTY.** |
| --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------- | -------- |
| [REV-41-1291](https://www.revrobotics.com/rev-41-1600/) | HD HEX MOTOR | 1 |
| [REV-41-1608](https://www.revrobotics.com/rev-41-1608/) | ULTRAPLANETARY PINION GEAR (ON HD HEX MOTOR) | 1 |
| [REV-41-1607](https://www.revrobotics.com/rev-41-1607/) | ULTRAPLANETARY MOUNTING PLATE | 1 |
| [REV-41-1602](https://www.revrobotics.com/rev-41-1602/) | ULTRAPLANETARY CARTRIDGE 4:1 | 1 |
| [REV-41-1603](https://www.revrobotics.com/rev-41-1603/) | ULTRAPLANETARY CARTRIDGE 5:1 | 1 |
| REREV-41-1604 OR
REV-41-1615
| ULTRAPLANETARY OUTPUT STAGE | 1 |
| [REV-41-1609-2](https://www.revrobotics.com/rev-41-1609/) | M3 X 30MM CAP HEAD SCREW | 6 |
| [REV-41-1609-5](https://www.revrobotics.com/rev-41-1609/) | M3 X 8MM BUTTON HEAD SCREW | 2 |
## UltraPlanetary Assembly Steps
| | |
| -------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|  | Attach the UltraPlanetary Mounting Plate to the HD Hex Motor using two 8mm Button Head Screws.
Note: Use the 2mm Allen Key to tighten these screws.
|
|  | Seat the UltraPlanetary 5:1 Cartridge onto the input pinon.
Note: Placing a finger on the output of the 5:1 Cartridge and turning it helps for placement.
|
|  | Seat the UltraPlanetary 4:1 Cartridge onto the UltraPlanetary 5:1 Cartridge.
Note: Placing a finger on the output of the 4:1 Cartridge and turning it helps for placement.
|
|  | Seat the UltraPlanetary Output Stage onto the UltraPlanetary 4:1 Cartridge.
Note: Placing a finger on the output of the Output Cartridge and turning it helps for placement.
|
|  | Insert six of the 30mm Cap Head Screws into the holes in the outer ring off the Output Cartridge.
Tighten these screws down until they are snug not tight using a 2.5mm allen wrench.
Note: The 30mm length is the 2nd longest screw provided with the UltraPlanetary Gearbox Kit.
|
|  | Attach the Pre-Loaded UltraPlanetary Flat Mounting Bracket and the Pre-Loaded UltraPlanetary Bent Mounting Bracket to the Output Cartridge using three M3 x 8mm Hex Head Screws. Tighten Screws until they are snug not tight. |
|  | Line up a 15 Tooth #25 Sprocket and a motion pattern spacer with the holes on the UltraPlanetary Output Stage. Use three M3 x 35mm Hex Cap Screws to attach the Sprocket and Spacer to the ighten screws until snug. |
|  | Use three M3 x 35mm Hex Cap Screws to attach the Sprocket and Spacer to the ighten screws until snug. |
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