OK, lemme see if I got this now. "Set screws" are ALL the screws that are used to hold the coil legs. "Grub screws" are only the ones that don't have a wider head on them, they're just straight up and down, and USUALLY use a hex key/allen wrench, but could also use some other tool to loosen and tighten. Is that about right?
Um, no, not quite. A set screw typically
threads into and
through one part to secure it to another. Like a pulley wheel to the shaft, where the set screw is recessed into the pulley and butts against the shaft, to keep the pulley and shaft turning the same. Hence the need for a headless screw.
Terminal screws that are not grub screws are just, well, small machine screws. In atomizers, often Phillips head, although some use socket head (hex key). If the atty uses grub screws, it has holes in the post for the leg, since there's no head to hold the leg.
(We make it to 4 pages yet?

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