REV ION Build System — Structure & Extrusion
Overview
Team 2890 uses the REV ION Build System as their primary mechanical structure system. ION is designed to enable rapid iteration and reconfiguration without large budgets or extensive manufacturing resources. The system is built around the MAXSpline — a unique spline shape that combines bearing support with torque transfer.
Core Concepts
MAXSpline
The MAXSpline is the foundation of the ION system. It appears in:
- MAX Hubs (for bearing and sprocket mounting)
- Live axle applications
- Motion components (linear slides, rotations)
The shape allows bearing support and torque transfer to be combined in a single feature — making mechanisms more compact.
MAX Pattern
The MAX Pattern combines:
- #10 clearance holes in a 1/2” pitch grid
- MAXSpline bore every 2” down the length
This pattern enables:
- Easy bearing mounting with correct center-to-center distances
- 1:1 power transmission with #25 chain or RT25 belting
- Rapid prototyping with standard #10 hardware
Grid Pattern
Some MAXTube features three rows of #10 holes on a 1/2” pitch grid. This is ideal for rapidly building structures with 1in brackets.
MAXTube Extrusions
MAXTube is aluminum 6061 extrusion. Available sizes:
| Size | Pattern | Length | Nut Groove |
|---|---|---|---|
| 1/2 × 1/2 in | Grid | 47in | No |
| 1 × 1 in | Grid | 47in | Yes |
| 1 × 1 in (1/16” wall) | Grid | 47in | No |
| 1 × 1 in (1/8” wall) | Grid | 47in | No |
| 2 × 1 in Light | No Pattern / Grid | 47in | Yes |
| 2 × 1 in | No Pattern / Grid / MAX | 3–47in | Yes |
| 2 × 2 in | Grid / MAX / MAX+Grid | 47in | No |
Nut groove note: On 1in sides, the nut groove holds #10 nuts in place where a wrench can’t reach. Use 2×1 Standard for secure bearing fit; 2×1 Light where weight is critical.
1in Extrusion (REV-21-1000)
4-sided slot extrusion accepting standard #10 hardware including low-profile nylock nuts. No T-nut needed — slide #10 hex head through slot, adjust as needed. Can be tapped 10-32 for permanent mounting.
Good for builds that don’t fit the standard pitch patterns.
MAXSpline Bore Spacing
For proper chain alignment: center-to-center distances are set for simple 1:1 #25 chain transmission. The MAX Pattern bore spacing every 2in makes this straightforward.
Connection to Training
For students: The ION system replaces custom machining. Understanding:
- Why standardized patterns matter — interchangeable parts, no custom drilling
- MAXSpline as a system — one spline shape across multiple components (hubs, bearings, motion)
- Nut grooves eliminate blind assembly problems — you can hold the nut while fastening
- Pitch grid = predictable spacing — 1/2in pitch means you always know where holes line up
Related training modules:
- swerving-modules — MK4i mounts to this structure
- motor-basics — how motors mount to structural extrusions
- frc-mechanical-basics — understanding structural systems
Source Links
- ION Build overview: https://docs.revrobotics.com/ion-build
- Extrusion guide: https://docs.revrobotics.com/ion-build/structure/extrusion
- Product catalog: https://www.revrobotics.com/ion-system/
Notes
Chris and team use this as their standard build system. The compatibility between ION mechanical and ION electrical (SPARK Flex, NEO Vortex) means the whole robot — structure, drivetrain, and motor control — uses one integrated system.