Engineering Guides

Plain-English explainers on the topics engineers actually have to get right — each links to the tools that do the maths.

GD&T Explained (Beginner Guide)

What geometric tolerancing is, the 14 symbols, datums, and bonus tolerance — in plain English.

How to Choose a Fit (ISO 286)

Clearance, transition or interference — picking H7/g6 and friends for bearings, dowels and press fits.

Tolerance Stack-Ups

Worst-case vs RSS vs Monte Carlo — will the gap actually close in production?

Tolerance Analysis in Practice

Defining the loop, gathering real tolerance data, choosing WC/RSS/Monte Carlo, and judging it against Cpk.

Reading Engineering Drawings

Views, title block, tolerances, surface finish and GD&T — how to decode a mechanical drawing.

Bolted Joint Design

Why preload matters more than torque, the nut factor, and designing a joint that survives fatigue.

Reading Weld Symbols

Arrow side vs other side, fillet vs groove, and what the numbers on the symbol mean.

Choosing a Welding Process

MIG vs TIG vs stick vs spot — matching the process to material, thickness and volume.

Press-Fit & Shrink-Fit Design

Interference, contact pressure, holding capacity, and sizing the fit between slip and yield.

Sheet-Metal Design Basics

Bend allowance, K-factor, minimum flanges and holes — designing parts that actually fold up.

Design for Manufacturing (DFM)

Design parts that are cheap and easy to make — draft, radii, wall thickness, tolerances.

How to Select a Material

Strength-to-weight, stiffness, cost and corrosion — a practical way to narrow the field.

Heat Treatment & Hardness

Hardening, tempering, annealing and case hardening — and how hardness maps to strength.

Surface Finish & Metrology

What Ra and Rz mean, how a profilometer measures them, and how to specify finish sensibly.

Corrosion & the Galvanic Series

Why dissimilar metals corrode, the galvanic series, and how to stop it in a design.

Coatings & Plating

Anodize, zinc, passivation, powder, DLC — what each finish does and when to specify it.

Fatigue: Why Parts Break

Cyclic loading, the endurance limit, stress concentrations and how to design against fatigue.

How to Size a Motor

Inertia, acceleration torque, RMS duty and the reflected-inertia trick with a gearbox.

Choosing a Bearing

Ball vs roller vs plain, load direction, speed, life and mounting — picking the right bearing.

Vibration Isolation

Natural frequency, the √2 rule, transmissibility and picking an isolator that actually helps.

Sizing a Power Supply

Rails, headroom, inrush, efficiency and thermals — picking a supply that survives real loads.

Grounding & EMI

Ground loops, star vs plane, shielding and layout — why the motor kills your sensor reading.

Choosing a Motor Driver

Brushed vs BLDC vs stepper drivers — current rating, PWM, protection and feedback.

Reading a Datasheet

Absolute maximums vs recommended operating, typ/min/max, and the notes that bite you.

Choosing a Sensor

Range, resolution, accuracy vs precision, output type and how to condition the signal.

Random Vibration Basics

PSD, Grms, the 3σ rule and why random vibration is nothing like a sine sweep.

How to Write a Stress Report

Structure, load cases, margins of safety and the traceability a reviewer needs.

Aerospace Fastener Selection

MS/NAS callouts, grip length, edge distance, hole class and why AN/MS matters.

Composite Layup Basics

Plies, orientation, symmetry and balance — why a laminate warps if you get it wrong.

FEA Pitfalls

Mesh, boundary conditions, singularities and sanity checks — getting FEA you can trust.

Reference aids, not a substitute for engineering judgment.