Alignment jigs and soldering blocks, 1
From the earliest days up to about 1966, it was possible to build
a respectable slot car chassis
without using a chassis alignment jig. In Bob Braverman's famous book,
This Is Your Hobby, Slot Car Racing, he builds a Slanted-motor Space Frame
without a jig. Braverman says of the chassis jig, gear puller, and vise, that they
"aren't absolutely necessary, but they simplify chassis building and
speed things up considerably." [Braverman, p 36 of 1969 rev ed]
Since about 1967, every professionally made chassis has been built
on a jig or a soldering block, to guarantee consistent dimensions, flatness, squareness
and rear axle height. Aligned chassis roll straight, their gears mesh cleanly, and they
don't scrape the track.