Manufacturing • GD&T • Fixturing

Suspension Manufacturing

Designing and building a precision suspension jig and repeatable workflow—targeting tight tolerances, faster setups, and clean assembly with zero shims.

The Problem

Prior builds showed tolerance stack-ups, inconsistent fixturing, and rework during assembly. The goal was a jig and process that locks to primary/secondary datums, reduces setup time, and delivers parts that assemble cleanly.

Challenge: Hold critical faces without distortion, preserve datums through operations, and manufacture the suspension system of the formula eletric car through processes.
Suspension jig on bench

The Solution

Jig plate with hardened pins

A modular jig system with hardened pins and adjustable locators aligns control features to datums. CAM sequencing protects reference faces and minimizes re-clamps.

Process & Tooling
GD&T (datums A/B/C) Modular jig + clamps SolidWorks & CAM CMM inspection 6061-T6, A2 steel

Development Process

1

Requirements & Stack

Mapped assembly stack-ups; set targets for flatness and true position on control features.

2

Jig Design

Modular plate, hardened pins, replaceable pads; clamps load near neutral axes.

3

CAM & Tooling

Sequence protects datums; minimized re-clamps; preset tools and holders.

4

Pilot Runs

Cut 3 parts, CMM feedback → small locator offset and finishing pass tweaks.

5

QA & Docs

QC sheet (in-process + final), torque order, and “don’t touch” faces standardized.

CMM program

Results & Impact

30
Parts, In-House

Manufactured inserts, extensions, steering column, uprights, and U-joint covers; mentored teammates and held ~0.005" machining tolerances.

$2.25k
Cost Avoided

When the vendor fell through ($2,600 quote), coordinated UC Berkeley CNC to deliver uprights in ~2 weeks for ~$350.

Jig
Welding Jig & FEA

Designed a reusable plywood jig that constrains 2 axes, works on all four sides, and was validated with FEA for suspension mass during weld.

Flow
Process Velocity

Leaned on planar parts (router/laser) and shop training/tolerance checks to keep builds moving over a ~5-month window while targeting ~0.05" system tolerancing.

Challenges & Key Learnings

Clamp Force Management

Thin-wall members distorted under high clamping loads — refining pad geometry and clamp sequence reduced part deflection.

Datum Protection

Machining around established reference faces first avoided tolerance drift later in the process.

Vendor Backup Planning

Having in-house CNC capabilities ready saved ~$2,250 and weeks of delay when an outside vendor fell through.

Process Documentation

Detailed torque specs, locator offsets, and inspection checkpoints prevented rework and sped up onboarding for other machinists.

Material & Thread Standardization

Consolidating thread types and material specs simplified procurement and reduced machine setup time.

Design for Welding

Laser-cut welding plates and FEA validation improved suspension-to-chassis fit while ensuring weld strength.