how it is attach? what are the measurement for making ti?
You can making this gear engine.But, it's not easy .. :-)
A sample drawing is required, 2d can be AutoCAD.
Which gear type is used, input / output cycle ratio is required for gears..
Design can be done by looking at photographs, but technical knowledge is needed to create a realistic project.
Using the SolidWorks library you can easily gear in 3D. You need to do research for information such as bearing system, axle distance measurement.
If you can not find any technical drawing, there is a benefit to doing research, to understand how it works.