rattleCAD 4.0 - Design Principle

What is it for?

This page describes what rattleCAD aims to be and the main concept, how rattleCAD 4.0 supports you to bring your Bike Fitting results into rattleCAD 4.0 to design and build your Bike Frame.


rattleCAD supports a lot of features that helps you to design a bicycle frame. But before describing all the features and how these features work lets take a look on the main concept rattleCAD is build arround.

rattleCAD 4.0 guides you throug a procoess split into 5 steps:

  • Bike Fitting
  • Geometry Skeleton
  • Frame & Tubes
  • Summary & Components
  • Workshop Drawings

Bridge the gap between Bike Fitting and Frame Building

rattleCAD 4.0 helps you to bring your Bike Fitting Values into Frame Building in the workshop.


rattleCAD 4.0 filling the gap between Bike Fitting and Frame Building in the Workshop

A Process in several Steps

rattleCAD 4.0 guides you throug a procoess split into 3 main steps:

and 2 minor but at least not unimportant steps:

  • Summary & Components
  • Workshop Drawings

A Process per definition means that:

  • each process step has a predecessor and a follower and
  • the preceding step influences the following process steps.
  • And of course: A following process never can influence a predecessing process step.
  • If you have to change a specific parameter you have to go back to the corresponding process step and continue with the process from here.

Five Process Steps

Initial Situation

To build a bike that fits best to the customer analyse riding behaviour in a Bike Fitting supported by a Bike Fitter or a Sport Scientist.


Step 1: Bike Fitting


The result of the Bike Fitting Process is the position of Saddle and Handlebar in reference to the position of the Bottom Bracket.


Step 2: Geometry Skeleton


The result of the Geometry Definition is a Skeleton defining the Geometry" of your bike. Along this skeleton you can build frames in different shapes.


Step 3: Frame & Tubes

Frame Chainstays

The result of this step is the refined Frame fitting best to you or your customer.


Step 4: Summary & Components

Mockup Mockup

This section allows you to finish the Bike Framewith components of your preference to get a first impression of the future bike.


Step 5: Workshop Drawings

Drawing Miter FrameJig

... export and print all required Workshop Drawings provided by rattleCAD.

  • Frame Drawing
  • Tube Miter
  • FrameJig Settings

Final Step: Build the Frame

... now it is on you and your expertise to build the Bike Frame.