The COG puzzle was inspired by (copied from) this project from Steve Ramsay - TheWeekendWoodworker. 

I have updated the plans and attempted to parameterise them in Autodesk Inventor.

This project should be fully parameterised so it can be easily modified depending on the size of the wood you are using.

How to update the model to your wood dimensions

1. Download the project files from above

2. In the cog_puzzle_parameters.xlsx file, input the dimensions of the wood you are using

3. Then update each model (Manage > Update)

4. The drawing will then show the updated dimensions

5. You can also update the assembly and check for interference between the parts

6. Make sure you activate the contact solver

Please let me know if the dimensions this generates work / don't work!

Working Drawings

These working drawings were prepared for wood 50mm x 20mm and 40mm x 20mm.