After any machine was received and properly filed by a major rebuilder, the first step in the actual rebuilding process was to tear the machine down.
Above, we see part of the disassembly area of the Smith Typewriter Sales Company in 1924. Several technicians seated at a bench are in the process of tearing down machines; the technicians standing at the rear are brush cleaning parts, which appear to be the frames of the machines devoid of operative parts.
Right here, it should be made clear that the specific parts original to one machine – say, its particular type bars or key levers – didn’t follow that machine through the process, in large factory rebuilding operations such as this. Instead, at the time the machines were torn down, badly worn or even broken parts were discarded right away. New ones would be put into the pipeline as available and/or needed so that, obviously, complete machines again came out the back end of the process, but the working parts had thoroughly been mixed up by that time.
What this means is that the technicians disassembling the machines weren’t just “shredders” taking the machines apart; they were able to examine the parts removed well enough to know if they should continue in the pipeline or not.