It strikes me that 622’s air pump will likely be one of the last detail castings I ever buy. Certainly, it will be the last brass air pump I buy. The next one will be printed, likely here at home.
It’s worth pausing here to enjoy the skill that went into the pattern for this little jewel. I suppose it must have been Bruce Bechtold who spaced those tiny bolts evenly around the cylinder heads, who assembled the minuscule valve glands and piston rod, who fashioned the cooling ribs on the air cylinder. I can only dream of being able to pull something like this together, and here we’ve been enjoying the fruits of his labour for 60 years. How many locomotives carry Cal-Scale air pumps like this one? What a legacy to consider that parts from his patterns are still carried with pride sixty years later!
Those great pattern makers and modellers at Cal-Scale, Kemtron and Precision Scale could not have predicted 3D printing. A printed part will enable me to tie the steam, exhaust and air pipes in without breaking any drill bits on age-hardened brass. I will design the supports into the part, and they will fit my boiler perfectly, without filing or filling. The space behind the piston rod will be space, and not filled in to enable casting. I may even create the part in multiple pieces to aid in painting and finishing. Oh yes, the 3D-printed air pump will offer many improvements.
But for now, I have enjoyed working with a tiny piece of art, and appreciating the ancient craft that went into it.