I must be a very, very darn good Craftsmen, for I can take a piece of pipe, two end caps, two springs, two marbles and a couple of faucet seat gaskets and build a compressor in less than 45 minutes!
Good job!
I forgot to specify and that was my point.
To specify details requires some thought, design, and understanding by other sub contractors. Building is easy once you have the raw materials machined into shapes that will work in your air compressor.
My point is that you do not have to make the materials from scratch, and if you did, it may take you longer than 45 min.
If I was to of given you a design, that I wanted to have you or I to build, like a Ingersoll Rand 4 stage compressor, with a 8 hp three ph. Motor, you may take longer if you had to start with raw materials.
You did support your build by doing theory. Your single piston compressor can be assembled faster than a working design can be completed on Wm2D.