Given that there has recently been an article in the mag. about machining metal to look like castings I thought I would take a picture of one of my attempts. It's not model engineering but full size but serves well to show what can be achieved.
The crank cases are for a 1929 Humber 350 O.H.C. engine, a rare beast indeed.I purchased along with my son in law a basket case restoration project. When we examined the contents we found that all there was left of the engine below the cylinder were the crankshaft main journals. Despite many adverts for a set of crank cases none were forthcoming.
Armed with a camera and tape measure I went to the National Motor cycle museum and got permission to take close up pictures and measurements of their Humber. I also found in the service booklet for my 1929 OHV a very nice drawing on tracing paper of the 350OHC Engine. Although only about 4 inches high and two views the detail on the drawing was amazing. I scanned the drawing and converted it using Auto Cad into DWG format. I was then able to scale the drawing back up to full size. I found, to my amazement that the dimensions of the drawing were accurate and measured well next to the main journals that I had, being within about .005".
From these drawings I was able to machine the crank case and timing case + Cover from the solid.

4 Pieces of HE-30 were used to make both the Crank Case halves as well as the inner and outer timing cover. The Humber logo was engraved using a Dremel by my son in law, don't ask me how he did it but I was amazed at the results.

Machining was carried out on an old Axminster round column mill using a 6" rotary table with a sub plate mounted on the rotary table to enable the 8" diameter (approx) billets to be clamped for machining.
I used mainly 5/8" did long series end mills some of which I had to braze extensions to to enable me to reach the depths I needed. I also used some woodworking Router cutters for radiusing the outer diameters and the inner corner radii etc.
I have done quite a few things this way and have successfully made my own pistons from the solid for both the Side valve and other peoples OHC Humbers.