In article , DoN. Nichols wrote:
In article 8SpCb.323522$Dw6.1095317@attbi_s02,
Loren Coe wrote:
In article , Lewis Campbell wrote:
I have a small lathe, similar to this one at Harbor Freight (
http://tinyurl.com/yy03 ) except that mine was purchased from Enco.
Anyway, I would like to be able to machine LH threads but this machine
does not have a reversible leadscrew.

i don't think lh threading requires reversing the lead screw. there
s/b good info thru google but i would be surprised if you cannot
reverse it on your machine. --Loren

The tumbler gears reverse the leadscrew on any lathe fitted with
them (unfortunately, not the one in question).

nor my Grizzly 3n1 (4015), not too surprising, i guess, but never had
a reason to wonder until now. what i thought might be a reverse is
simply a clutch which allows you to do manual feed using the lead
screw.

As already mentioned, adding an idler gear to the train (as long
as you can find a place on the crowsfoot to mount it (or whatever the
equivalent on the Enco lathe might be)) will accomplish the reversal, if
not as conveniently as the tumbler gears on larger lathes.

so, besides lh threads, what would this reverse mode be good for? probably
a dumb question(?). you could take cuts in both directions under power, what
else, tram under power? you can reverse the motor for that. Thanks! --Loren


The actual count of teeth in the gear doesn't really matter that
much, since it is just working as an idler -- just find one which will
fit between two gears in the existing train.

Good Luck,
DoN.