A lot of information an be found online by searching "9x20 lathe". This
lathe, and many others can produce many more thread pitches thn listed in
the owner/operation manuals.
The typical 9x20 models can cut both meteric and inch threads. More
threading info is shown in the chart in the 2004 dropbox files.
There are a lot of 9x20 owners' websites that show various improvements and
modifications they've done to their lathes.
Some comments describe the 9x20 model to be a kit, of sorts, meaning that
the lathes aren't considered to be ready to use as delivered. Disassembly,
cleaning, adjustments and fabrication of improved parts are considered to be
necessary to attain good performance with the 9x20 models.
In comparing various models, check that various models have all the same
features, since many lower priced models have fewer features.
Accessories included from different sellers may vary, as far as faceplate,
steady rest, centers, chucks, etc.
Of particular interest while comparing, check to see if models have a quick
change gear box, the same controls on the apron for threading and turning
feeds, comparable spindle speeds, clearance over the cross slide, and
similar accessories included.
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