- Do I want to make it? Putting it all on paper is this something that I want to make or has it lost its luster or drive?
- Can I make it? Is the design too complicated to make, are the parts too dangerous to make or there are too many things that I do not know how to do? This is just a question of safety and capability.
- Is it going to fill its purpose? I really don't want to make something that will just get by for a short season. I do not want a piece of furniture or toy that will only be temporary or break after a little bit of use.
Now it is making the parts and assembling. Take notes on the drawings of things that come up, either wrong dimensions or changes that would make the project look better. For example, the train cars looked better with the sides inset on the floor than flush.
Once the prototypes is done make it how it was designed.