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Saving a 1943 Springfield Engine Lathe, Part 13:
At some point in this machine's storied history, the original motor got replaced. No idea why- the old
one may have failed or worn out, or was an odd voltage, who knows. Since the compound had also
been replaced at some point, I've occasionally wondered if this wasn't some kind of salvaged machine-
perhaps an old military auction, sold as parts but rescued and reactivated. Just a theory, though,
Anyway, the "new" motor is a pretty hefty 10HP Emerson. It was dusty and
dirty, but spins smoothly and noiselessly when turned by hand.
This motor is a relatively standard 1745 RPM unit, whereas I strongly suspect the original motor was
probably an 1125/1140 RPM one. No problem, really, the spindle speeds will just be about 1/3rd faster.
The only issue was the wiring- somebody had simply twisted a few wires together, and covered
the unions with black electrical tape. There wasn't even any sort of strain relief.
Twisted together and taped. Functional, but not exactly elegant.
I terminated the ends a little more properly, bundled the 'sets' of leads with a collar of heat shrink...
And added a not quite correct but servicable 90-degree elbow to the junction box (which was
also flipped over) and coated the connections with brush-on liquid electrical tape.
Over the brush-on stuff, I added thick sleeves of glue-lined
heat-shrink, as an extra layer of insulation and abrasion-resistance.
Tucked into the junction box...
... and a couple of custom-turned Delrin collar bits to wedge the cable into the elbow.
The elbow was meant to screw into flexible conduit, but hey. It'll serve just fine.
Aaaand... I guess that was it, really. Nothing else to do. The pulley was a little rusty, but nothing major.
It's a heavy duty taper-lock on a 1-1/4" shaft, so I think it'll survive.
The hardest part was sliding that heavy bas...
... er, thing into the headstock base. But after a few choice four letter words, seasoned with the occasional
fourteen-letter for a little extra zing, I got it in and bolted down. I left myself plenty of cable, though I at this
moment am still not completely sure what I'll be doing for wiring. I'm hoping to go with a VFD, though the only
10HP, single-phase-in unit I can find is over a grand.
I've toyed with dropping it down to a Baldor 5HP motor
I have, as I doubt I'll ever need a full 10HP, and both a 5HP VFD and a presumably
lower current draw will both be something of a money saver.
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