I have a specific question about cutting threads on a Frejoth (Chinese
or Taiwanese import lathe). I have set up the gears and the gear box
for the desired threads, but I cannot get the threading drive to turn.
There is a forward-neutral-backward toggle that works fine to turn on
and reverse the feed. I cannot find any way to get the other screw
thread bar to be driven by the drive train. I know this sounds very
lame, but I just do not see any other toggle or switch that would
engage it.
Here is a picture of the lathe:
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There are only six toggle switches and all of their functions appear to
be accounted for.
I would welcome any advice.
Thank you.
Scott
PS-I got it used and have no access to a manual. Grizzly lathes of a
similar make have a thread/drive toggle.
Does that mean that the lead screw isn't turning?
If it doesn't turn, its one of the levers on the spindle stock. Without
manual, you're lost. Find a similar looking model at Grizzly or whatever or
contact the manufacturer and test their customer service for a manual.
With some (or a lot of) luck, you can find the right lever. Look at the
markings for the levers. Find one that looks like it is in between the
normal distance between all the other markings. Set the lever to this
position.
Nick
Also, pull the end cover off and make sure you have a gear on the end of
the lead screw. You never know, the PO may have removed it for some
reason.....
==============
If by toggles you are referring to electrical switches this may
be what is distracting you as this is most likely controlled by
manual gear changes. On many, but by no meas all, lathes there
is a three position lever at the headstock. One position causes
the lead screw to rotate one direction relative to the rotation
of the spindle for right hand threads, one position is neutral
where the lead screw does not turn, and one position reverses the
direction of rotation of the lead screw relative to the spindle
to generate left hand threads. On my Emco compact 10 there is no
external lever but you have to open the cover and manually shift
positions, and this may be the same for your lathe.
Frequently this is referred to as a "tumbler."
see
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1/3 way down the page to see what you are looking for.
For an internal tumbler as used on my Emco click on
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look at page 24
Good luck, welcome to the world of machining and let us know what
you discover.
Unka' George [George McDuffee]
============
Merchants have no country.
The mere spot they stand on
does not constitute so strong an attachment
as that from which they draw their gains.
Thomas Jefferson (1743-1826),
U.S. president. Letter, 17 March 1814.
===========
Also some people have suggested that Harbor Freight and Acra are
selling the same lathe under their brand name.
check out
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Harbor Freight will have manuals on line that you can download
Unka' George [George McDuffee]
============
Merchants have no country.
The mere spot they stand on
does not constitute so strong an attachment
as that from which they draw their gains.
Thomas Jefferson (1743-1826),
U.S. president. Letter, 17 March 1814.
According to Scott :
The photo (from a site in Taiwan) does not have sufficient
detail of the headstock controls to enable me to determine their
functions.
Look for one which has a marking like:
/\/\/\/\/\/\/\/\/\/\
which is the threading setting. The same control thrown the other way
will rotate the feed rod instead of the threading leadscrew. (I seem
to remember that on the Taiwanese lathe which I used something like
fifteen to twenty years ago, there was a mushroom shaped button down low
on the panel which was pushed in to do threading and pulled out to do
feeds. I suspect that it is the bottom-most lever on the illustrated
machine.
Check whether any of the toggles push in or pull out when in the
neutral position. That might be how it switches between threading and
feeding, and uses the same lever to switch directions for both feeds and
threads.
It looks as though it has a threading chart on the cover to the
left of the main panel.
Could there be some gears missing under that cover? That is
where you change the gears to do either metric or imperial threads if it
is like the one which I used.
Have you tried searching their web site for a downloadble
manual?
Anyway, you have what little I can offer without a better photo
(close-up) of the controls and the threading/feed charts on the cover. *Don't* try to e-mail me a photo -- it won't make it through my
spam filters unless it is too low a resolution to do me any good. And
*don't* post it. Upload it to the dropbox (see
formatting link
for instructions) and then post the URL for the photo here.
Good Luck,
DoN.
Did you engage th' half nut? It's th' farthest lever on th'
face/front of th' carriage towards th' tailstock on my Central
Machinery 12x36. You have to turn th' carriage handwheel a touch to
get it fully engaged.
There should also be a *thread or feed* lever on th' headstock...
prolly th' lower one closest to th' tailstock end as it lines up
horizontally with th' lead screw. My guess is *thread* is in th' up
position. Mine has a symbol like this -wwv- for feed, I can't do th'
thread symbol in ASCI, but it looks like a bolt with a centerline
through it.
Finally, there should be a thread cutting dial you'll need to engage.
It's on th' tailstock side of th' carriage and has a worm drive that
when turned CCW engages with th' lead screw threads.
If that doesn't work, email 'em: snipped-for-privacy@frejoth.com.tw or call:
886-4-23816977 and ask for a manual.
Disclaimer: Mine looks *kind of* like yours, but still different
enough to not be positive about your settings.
Snarl
At a guess from the picture and similar looking chineser lathes.....
Two top levers ...... rpm of hadstock
Lever below to left on second row .... forward/reverse direction of lead
screw/cross feed in relation to headstock
Next row of two levers control gear ratio's for of lead screw for feed and
thread cutting. One lever wil have 7 or 8 positions ( depending on number of
threads capable of cutting) The other will most likely have 4 positions ...
lets call them A B C D. A and C will be for lead screw and B and D will be
for cross feed.
The bottom lever below and to right of oil level sight glass will
engage/disengage the lead screw/cross feed
Bottom lever
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