Engineering, made buildable

Engineering design tools for makers.

Real engineering standards, made simple. Design mechanical parts that actually work — verify them against the same methods professionals use, then export print-ready files. No engineering degree required.


The Toolbox

Design tools, one membership

Each tool turns a hard engineering calculation into a few sliders and a download button. Members get access to every tool — current and future.

Live · VDI 2736

Spur Gear Designer

Polymer spur gear designer — VDI 2736 based. Design, verify and export printable gears.

Launch → 🔒 Members
Live · VDI 2736

Helical Gear Designer

Polymer helical gear designer — helix-angle control, axial-thrust & overlap-ratio analysis, VDI 2736 verified. Design, verify and export.

Launch → 🔒 Members
Coming soon
Planned

Shaft Designer

Size shafts for torque, bending and fatigue — with keyways, fillets and a safety-factor check.

🔒 Members

How it works

From idea to printable part in three steps

STEP 01

Set your parameters

Enter what you know — load, speed, size, material. Plain inputs with clear explanations, no jargon you don't need.

STEP 02

Verify the design

The tool runs the real engineering checks (stress, safety factor, temperature) and tells you if your part will hold.

STEP 03

Export & print

Download a clean STL for your 3D printer and a PDF engineering report documenting every result.


Inside the Spur Gear Designer

What it actually calculates

This isn't a shape generator that just draws a gear. It runs the real polymer-gear engineering checks from the VDI 2736 standard, so the part you print is one you can actually trust under load.

Gear geometry

Define a true involute gear from the parameters that matter:

  • Module, number of teeth, pressure angle
  • Profile shift (x) for stronger or fitted gears
  • Root fillet radius & tip/root diameters
  • Single gear or a meshing pair with ratio

Strength & safety (VDI 2736)

The core engineering verification for plastic gears:

  • Tooth-root bending stress (σF)
  • Flank / contact pressure (σH, Hertzian)
  • Safety factors SF and SH
  • Pass / fail verdict for your load case

Thermal & wear check

Plastic gears fail from heat, not just force:

  • Flash & bulk tooth temperature estimate
  • PV (pressure × velocity) loading
  • Indicative wear & service-life guidance
  • Warns when a material runs too hot

Material library

Pick your real printing filament — properties are built in:

  • POM, PA66, PA12, PA-CF, PETG, ABS, PLA, PC, TPU
  • Custom material option for your own data
  • Print-strength derating for FDM parts

Hub, bore & fit

Make it a real, mountable part:

  • Round bore, D-flat, keyway (DIN 6885-1) or hex
  • Hub diameter & length
  • Clearance / fit allowance for printed parts

Exports you can use

Take your verified design straight to the bench:

  • Print-ready STL (generated on our server)
  • Full PDF engineering report of every result
  • Save / load your design as a config file

Also included

Live 3D preview & mesh animation
Working pressure angle & centre distance
Contact ratio calculation
Pair kinematics: torque, speed, efficiency
Profile-shift optimiser (balances root safety)
Basic & Advanced input modes

Core gear geometry & VDI 2736 stress results are calculated precisely. Thermal, PV and wear figures are indicative guidance — for critical or load-bearing parts, confirm with physical testing.


Getting access

How to subscribe & sign in

Access is handled through Patreon. It takes about two minutes — here's exactly how, step by step.

Go to Patreon

Open patreon.com/dryrockdesign in your web browser. Tip: join from a browser (not the phone app) to avoid Apple's extra 30% fee.

Pick the right tier

Choose a tier that includes the tools:

All Designs + Engineering Tools Commercial License

Either one unlocks every tool on this site.

Complete your pledge

Finish the Patreon checkout so your membership is active. Discounts, promos or gift codes are fine — access follows the tier, not the price you paid.

Come back & sign in

Return to dryrockdesigntools.com, open any tool and click Sign in with Patreon. Approve once, and the tool opens.

Already a member? Just open a tool and click "Sign in with Patreon". · Just joined and still blocked? Wait a minute for Patreon to activate, then try again.


Watch the guide

See a tool in action

A short walkthrough of the Spur Gear Designer — from first slider to printed gear.


Before you start

What you need to run the tools

Everything runs right in your web browser — there's nothing to install, no plugins, and no Java. You just need a reasonably modern browser with JavaScript and 3D (WebGL) enabled, which almost every device already has.

A modern browser

Use an up-to-date Chrome, Edge, Firefox, Safari, or Brave. Keeping it updated (latest version) gives the best 3D performance. Internet Explorer is not supported.

JavaScript & WebGL on

The 3D preview uses WebGL, and the tools use JavaScript — both are on by default. No Java, no Flash, no downloads. If 3D looks blank, enable hardware acceleration in your browser settings.

Desktop or mobile

Works on Windows, macOS, Linux, and modern tablets/phones. A desktop or laptop is recommended for comfortable sliders and larger STL exports.

A Patreon account

Tools are members-only. You'll sign in with Patreon (an active tier that includes the tools). See the steps above to get access.

Access every tool through Patreon

One membership unlocks the full toolbox — and everything we build next. Sign in with your Patreon account to launch any tool.

Sign in & launch →
Tip: subscribe on patreon.com in your browser to avoid the extra 30% Apple app fee.