Tool To Create Folding Plans I'm trying to design a leather box, I've got the plan penciled out - but now looking to create a scale model out of card.

I'm looking for a tool that will allow me to make my scribbles into a to-scale print out which I can then use to take the project forward.  Something similar to: 



A free or cheap software tool would be ideal.

Thanks guys
I had to do something similar recently.

Starting with a pencil sketch and a cutout (could be just a sketch in your case), I took a picture of it using my phone:


I imported the picture into FreeCad (yes, it is free) and used its Sketcher workbench to trace over the image. That produced a "proper" engineering model (where I could control sizes, placement of elements etc):



I then used Drawing workbench to create a technical drawing which I exported to PDF at scale, printed it out and in my case glued to cardboard to cut the final box out of:



Now, I must warn you that the learning curve of FreeCad is pretty steep, but I think it is a great tool to keep in your toolbox.