All righty, then. It would appear that the chuck is most likely a screw tight
rather than a sprung, as it has the three knurl bands with two grooves. This is
what I was not sure of. Thanks to Jack and the others that direct emailed me
with information. I have not possessed a '44 before, and didn't know if the
chuck styling was the same as the other yankees I have (a motley crew, they
are).
I'll give it a few more days with penetrating oil, then, if needed, heat and
maybe liquid nitrogen. There is a bit in it, and it is free to rotate a few
degrees since the first application of penetrant. This means that, most likely,
either the threads are rusted solid, or the collar was cranked so hard that it
galled in, and, if the oil doesn't free it, 100 or so degrees difference between
the collar and the body will give maybe 0.01mm clearance, and, hopefully, free
it up.

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