I'm not saying these things to piss people off, honestly! I was trying to
give a straight honest answer based on my experiences with the Jet BD920N.
Perhaps I got an absolute lemon unit that doesn't represent the average unit.
If so, then I hope their QC has improved, after all - they crated and sold it
that way. The lathe was shipped to me from the JET warehouse, it wasn't
purchased at some traveling tool carnival. I don't agree with all of your
"The 7x10 and 9x20 import lathes are popular because, although they DO
have faults; the faults are well documented, correctable (largely),
and CONSISTENT. You cannot say the same thing about going out and
getting an old SB. They are all over the map, condition wise... And
you had better know what you are getting, or you can EASILY get "just
as" burned. Finally, a GOOD SB beats a "stock" 9x20 every way to
You're right about used gear, a person has to know what to look for, and their
limits when it comes to repair. Not only in available tools and knowledge,
but also in perseverance and body strength. Some things just have to be
picked up. If they weigh too much, you need a helper. OK if you have one,
not so OK if you work alone. Not everything can be picked up with an engine
crane. You can get the knowledge in many cases with a little work, but
sufficient tooling can be rough. If you have to pay a machine shop several
hundred dollars to do work you can't handle you need to understand this up
front. I've rebuilt auto engines, farm tractors, and some other fun things,
so have a bit more experience that applies than some folks.
The 9x20 lathes are NOT consistent, I've spoken with folks that had very few
problems, and with folks that have had problems worse than mine. The faults I
have heartburn with are NOT the fit and finish sort of problems - you can't
polish everything and sell it for $895 after all, or with design limitations,
everything has limitations. As you have created a group for these lathes I
imagine that you have a better idea about the current state of QC at the
The faults that bother me are the gross defects in the manufacturing and
inspection process. The design limitations are indeed mostly correctable, and
have recently become quite well documented from a number of sources. Most of
the "fit and finish" class of improvements are indeed fairly simple
straightforward clean it up shine it up sort of work that is a pleasant way to
spend a rainy day.
I can't comment on the 7x10 lathes as I've only used one once at a meeting -
other than to say that I was quite impressed with the unit I saw, and think
that they are quite a lot of lathe for the money! Perhaps they are more
consistent than the 9x20 units.
Old gear is all over the map. Beaters and perfect condition units in the 9
inch size go from $300 to $3500. Funny thing is there are some great lathes
for $500, and some beaters for $2000. At least when a person buys used, they
tend to be careful to look very closely or seek advise from someone who can
help them avoid getting ripped off.
I think the basic reasons the imports are so popular are the same reasons I
bought one. A) You can get one. Today or within a week. B) They are
affordable. I don't think that folks are buying them because all of their
faults are known and documented, although no doubt many folks buy them knowing
what they are getting into courtesy of groups such as this one, and that's
fine. It's the folks that buy one trusting Jet to provide a good lathe out of
the box ( as I did) that get screwed and then angry or so frustrated that they
give up and find something else to do. Some get lucky and use the web to get
As to a good SB being better than a stock 9x20, that is probably true in most
cases, but there are some other considerations. If you like carbide, older SB
lathes with sleeve type headstock bearings don't like to run at over around
1000 RPM, with the Workshop series having a max delivered speed of around 700
RPM with a standard spindle. I run the Jet at 1000 and 2000 quite often when
using carbide. The Jet and other imports can cut metric or standard threads
without much fiddling. Converting an older SB to metric may or may not be
easy, depending on the pitch you need to cut. Converting a really old SB to
metric may well be impossibly without fabricating some pieces yourself. Older
SB lathes will have a lantern type toolpost. You'll likely want to make a
four way or mount a QC toolpost. The Jet has a semi QC gearbox, many of the
used SB lathes will be manual change gear style lathes. I guess it depends on
if the 9x20 is one of the good "stock" units or one of the much work required
"stock" units ;-)
The basic accuracy of the Jet is excellent if you ignore metric leadscrews
with imperial dials. It can cut straight and face square. Doing this well
and repeatably with good finish is where the interesting parts begin. You can
make a 9x20 into a pretty good lathe, it just may take some doing.
To me, the largest problem with these lathes is that they are likely to be a
first lathe, and without help from someone who knows the tricks and can tell
the difference between machine failure and user failure it can get really
frustrating. Without access to another lathe, possibly a mill, and a fair bit
of tool rebuilding experience it can be really tough to sort out the problems
with these lathes. Remember that in 1995 there was no 9x20 group, and a lot
less web support for HSMs. CAMS - the once a month "club" - didn't exist, and
our few folks are scattered over PA, MD, DC, and VA. I was the only guy with
a lathe I knew. A person with no experience can easily end up with a used
lathe that is worse than a new import, no doubt about it. If I hadn't spent
years building and rebuilding assorted optical and electromechanical gear and
doing a lot of auto repair I wouldn't have known where to start. When I
bought this lathe I hadn't had a shop class since 1972, and hadn't touched a
metal lathe other than (rarely) some large South Bends and such since high
school, and had changed jobs and states so I couldn't get a hand from the guys
I knew at the old manufacturing plant. I kept thinking that problems caused
by the machine were problems caused by me. It took a lot of digging in books,
trying things out, and devising tests and figuring out what to measure and how
to measure it to decide when it was me goofing, and when the machine wasn't
quite right. I certainly learned a whole lot, both about lathes and how to
focus the energy of frustration. I asked myself "What am I doing wrong?" a
lot. Sometimes it was me, often it was the lathe.
The thing that really ticked me off was that I had no other lathe and no mill
at the time, so I paid extra for the Jet name just to avoid these problems. I
have other JET gear (from Taiwan), and think that all of the Taiwan Jet stuff
I have is a good value for the price. I didn't expect a South Bend, Clausing,
or Logan for the price paid. I just didn't expect to find grinding grit and
casting sand under the cosmoline, to have to replace half nuts and lead screw,
lap gibs, relieve dovetail corners, remove grit from inside assemblies,
replace the compound because they didn't mill it before grinding so tools sat
.093 high, deburr gears and the entire leadscrew (both the original and the
replacement) keyway, polish shafts, polish and reduce the diameter of the
spindle to let the headstock bearings be adjustable, have to replace ALL of
the soft junk hardware, buy a MT3 reamer to clean up the inside of the
headstock spindle, and on and on. With the exception of not having to deal
with bed wear problems or repainting, my lathe was on par with a beater in
terms of the amount of work needed to get a usable lathe. A grit laden
sliding surface with burrs is the same problem, whether due to wear or poor
manufacturing is beside the point.
You'll notice I didn't mention finish/cosmetic items in the above paragraphs.
I expect import handwheels to be a bit rough, the paint to be something other
than auto show pretty, and a bit of tweaking up and smoothing to be in order.
I just don't expect the head to strip out on a socket head cap screw on first
removal, to find tapping swarf in the bottom of blind holes, or grinding grit
in the dovetails. I don't consider gross failure to function as advertised or
having hardware strip on the first use to be a "project", I consider it
defective merchandise. When the leadscrew strips off the crest of the half
nut threads the first time the nuts are closed, because they didn't deburr the
keyway, it is a defect, not something that wants improvement. Making the
knobs smoother, the graduations more legible, the fit nicer, the gears a bit
quieter are all improvements to fit and finish. Having to use sockets and a
vise to press apart the change gears from the shafts that they are supposed to
slide on and off of are defects. Making them do it silky smooth is an
improvement. Keyways in gears that are crooked are just lousy workmanship.
Heck, I broach keyways that end up in the right place in a home shop. It's
rather difficult to mess it up if you use the right tools. You expect a
company like Jet to use factories that can at least match a home shop guys
basic tool skills.
Jet was very good about warranty parts, and had most things in stock. The
problem was that so many parts needed replacement.
Getting the Taig for small projects actually opened my eyes to how many of the
problems with the 9x20 were tool and not user deficiencies. The Taig is so
good out of the box. Now I could compare the same tool cutting the same
material at the same speed on the two lathes. Something a bit more concrete!
Room for improvement is fine, a machine that is unusable out of the crate
other than cleaning off the cosmoline and tweaking normal user adjustments is
not! My Grizzly mill was cutting metal the same day it came into the shop.
I've made some minor modifications and improvements, trammed the head, and
added power feed, BUT - it worked as delivered. My Jet drill press poked
holes just fine right out of the box. The Taig was a delight the first time I
used it, a few minor improvement simply make it better.
I looked for a good used lathe for about 6 years before getting the Jet, so I
know that many of the old lathes out there are beaters. I spend two days
grinding the bed on my 7 foot SB13 using home made fixtures, so I also know a
bit about beaters as well as creampuffs.
I've said a number of times that making chips today on darn near anything
beats the heck out of wishing and waiting and not doing anything.
Since you asked:
I'll talk about the cost of a beater farther down ;-)
The total cost to restore this particular SB9 was about $80:
3 cans Aircraft stripper - $15
4 cans Primer (Rustoleum professional gray primer) - $18
4 cans Color (Rustoleum professional light machine gray) - $20
a bit of spot putty - already had it but if not it would be about $4
Brass polish - $2.50
Perhaps 10 to 15 dollars in shop "stuff" - 10 sheets or so of assorted grit
sandpaper, two stripping pads, some quantity less than 9 of scotchbrite pads,
newspaper and tape for masking, single edged razor blades, odds and ends (e.g.
hard wool felt for oil wicks) as expected for any tear down, repaint, and
2 gallon cans of mineral spirits - $3
A new drive belt - $8 at the local auto parts store, I'm using a serpentine
fan belt rather than a leather belt, this has worked well on other tools. If
I have to buy leather and glue or lace up a "genuine" flat belt, that's fine,
it remains to be seen.
Dollars still to be spent: A good live center and tailstock drill chuck on a
MT2 arbor. Yes, I can use the ones I have for the Jet, but I like each tool
to be complete as far as basic tooling goes.
The lathe was purchased for $500, including a lot of tooling, including steady
rest, follower rest, three and four jaw chucks, face plate, dog plate, several
dogs, about a dozen toolholders, complete change gear set, motor, jackshaft, a
somewhat worn Skoda live center, several dial indicators (Starrett and old
Brown and Sharpe) on various holders, and other random stuff. The owner built
bench with drawers was included - hot riveted construction, a conversation
piece at the least. It was cosmetically ugly. It is mechanically excellent
in almost all ways, the only exception being the bit of scoring on the
spindle, which could not be detected until the teardown. I could likely have
ignored it, the spindle felt fine as it was, but cleaning it up is all part of
doing the job right.
TIME: About 40 hours actual work, including two hours work on the spindle and
front bearing as there was a bit of swarf that had crept in and scored things
a bit. Part of this time was making a lap for the headstock bore. I've spent
more time that this sorting out faults on the Jet 920. The experience gained
on the Jet really didn't map to this job, as SB made the parts right the first
time, and the previous owner had treated the lathe well. With fresh oil
added, this lathe could have been used as it was. I made one new headstock
clamp plate, one of the originals had a crack. The original cracked one
worked, but what's an extra half hour at the mill compared to knowing there is
something waiting to fail left unfixed?
About an hour went into making a 12-28 tap to clean out some holes I let some
paint wick into, and making a tool to remove the handwheel hardware. I could
have bought the tap mail order, but making one only took about 15 minutes as
it only had to chase threads, not cut new ones, so a single flute made with a
triangular file was adequate for the intended use. If a real tap was
available locally I would have bought one, I just didn't want to stop the
project for a week waiting on delivery.
This lathe was in a guys basement from the time it came out of the crate in
the late 30's (1939 I believe), and still has original scraping and frosting
visible on most surfaces. Some quick sanity checks on the surface plate
showed no problems, so for once a rebuild was actually just a restoration. No
scraping needed. I didn't need to ask for any help from others other than my
neighbors time to help unload the lathe from my truck as he had my engine
crane tied up in his shop.
POSSIBLE DOWNSIDE ISSUES of rebuilding used lathes.
You can get in to a project that isn't worth doing. If the 13 inch lathe
below was a 9 incher, the salvageable parts would have been sold and the bed
scrapped. A new 9x20 import does beat a severely ragged SB9!
Watch out for oddball lathes! Old SB 13 and 15 inch lathes have a non
standard spindle taper, and may have odd leadscrew pitches, such as 6 TPI.
Some of the 13 inchers have a 1 7/8-8 spindle nose, so you're going to machine
any faceplates and backing plates from raw castings if you can't find them on
the used market. If you can handle this weirdness fine. If not, move on to
Big lathes have BIG HEAVY parts. Don't buy one that needs a tear down unless
you can deal with this. There are things that a normal human just can't
lift. Don't hurt yourself, use an engine crane, a trolley crane, a boom on a
three point hitch should you have a tractor, sufficient helpers, whatever. My
neighbor is refurbishing a 15 inch South Bend from the 20's. There are
castings in the overhead drive that he and I can't lift together.
UPSIDE STORY - The above mentioned 15 inch lathe is in mechanically excellent
condition. It is a lot of heavy work, but for the $300 purchase price plus
about $400 for a second chuck and repainting materials he will have a 15 inch
swing 6 foot bed lathe. It isn't quick change, but all of the gears are
there. Pretty sweet if you need a lathe of that size! His job will involve
about 50 hours work total.
STORY OF A BEATER REBUILD:
I have done a true beater SB13 with a 7 foot bed. It was rusted solid, the
power feed worm teeth were at least 1/5 gone to rust where the wheel in the
apron was pressed down into cow bedding in the bottom of a partially collapsed
barn. We skidded it out with a front end loader. What was I ever
thinking?!?!?! The ways were so worn that the saddle would rock at the
headstock end. It took two days just to grind the bed using a die grinder,
home brew fixtures and gages, and a lot of testing and tweaking. No local
shop could (or would) plane a 7 foot bed. Trucking the bed back to SB was out
of the question, shipping both ways and the cost of planing the bed for a
lathe with many other problems was not on the list of options. Parts had to
be made. Several cast iron tooth inserts were made and silver soldered into
milled slots to replace missing teeth on the back gear. The carriage had to
be electrolytically derusted to get it apart. The spindle bearing surfaces
were a mess, so I rigged up a makeshift toolpost grinder and redid them.
Testing with Plastigage confirmed the job was in spec. It isn't what I'd call
100 percent done yet, although it is under power and doing good work when a
lathe of this size is needed. Looks nice with a good paint job on it.
A job like this can easily turn into hundreds of dollars more than expected
(thousands if you buy replacement parts, I was quoted $350 for just the worm,
so I built it up with braze and recut the teeth). You need to be able to hump
100 pound castings around, work on them, and not screw up. You need a mill
that can handle large hundred pound parts. The bed alone weighs about 500
pounds, just painting it is a real upper body workout to move it around and
roll it over to get to each side. The legs are about 80 pounds each. This
one was a real nightmare job that I nearly gave up on several times. I'll
guess that at least 200 hours have gone into this lathe, with about 30 hours
to go, mostly in gearmaking and making some new leadscrews. More than once it
almost became a wood lathe!
Before someone jumps in and says that most or all of these parts are available
from industrial suppliers, I should mention this lathe was built in 1929. No,
you can't get a matching worm wheel and bore it out to press fit or silver
braze onto the original hub. I've done this on other machines. I have most,
perhaps all, of the US gear manufacturers catalogs. You can't get a 44 tooth
worm wheel in this pitch. 45 yes, 44 no. I'll likely make a hob to match the
worm and make a whole new power feed worm/clutch part. South Bend has no
parts or info available. You can get 5/8-10 LH acme leadscrew though, so
there is a source for the threaded portion of the cross slide lead screw!
I could have shaved 30 hours work off the job by cutting the bed down, but a 7
footer is pretty rare so it was worth the work. It is at the point that the
bed is within 1.5 thou total up/down variation over the entire length, in/out
to centerline variation is maybe 2 tenths - hard to measure this accurately on
a lathe with bronze rather than roller bearings, and spindle runout is < 1
tenth. No sudden variations, just a nice smooth needle on the indicator.
I'll chase a thou when needed without hesitation, chasing a tenth can become
The 1.5 thou variation up/down ends up not meaning much of anything, it you do
the trig for any work larger than around a half inch, you find the change in
diameter from this source is down in the noise. For a one inch diameter
workpiece, you find that the cutter moving down 1.5 thou translates to a
finished diameter of 1.000005 rather than 1.000000. A twentieth of a tenth
isn't on the list of things I'm going to loose sleep over. Variation that
moves the carriage in or out is critical though, as any error translates to
double the error in the diameter, and is a constant error independent of
Cost to rebuild? Don't know. At least $600 so far, and I still have to make
a backing plate (1 7/8-8 spindle - you can't buy these new although this
thread does show up if you put out feelers to folks that won't shaft you when
it appears) and fit a nice 10 or 12 inch 4 jaw. I already had most of the
large tools - engine crane, > 1 inch wrenches, large sockets, 20 ton press,
and still dropped a fast $100 at Sears for some sizes I needed. Ever noticed
the cost of big wrenches?
Was it worth it? To me, yes. Although I underestimated the effort required
on this one a bit, I learned a lot and got to try out some new techniques. I
have a 1200 lb lathe with 54 inches between centers and a 13 1/4 inch swing.
The lathe cost $100 to buy. For a total cost of around $1000 including a new
4 jaw chuck, I have a large lathe that can cut 2 to 112 TPI including some of
the oddball 1/2 thread pitches, and has power cross feed. I have a nice Rohm
6 incher with removable/reversible jaws I lucked into for $70 that will end up
mated to this lathe, right now the original Cushman 3 jaw is on the lathe with
freshly ground jaws. I need to make or find a threading dial, like most
things on this lathe, it is an oddball as the lead screw is 6 TPI.
Would it be worth it to you? Can't say! About half of the time on this lathe
was interesting mechanical and machining work, the other half was nasty,
dirty, and occasionally heavy labor that I didn't enjoy much after the first
40 hours or so. Getting something rusty but cool apart the first time is kind
of neat, looking over a pile of rusty things still to get through can be
demoralizing. By the time you're done, you really don't want to see something
else old and rusty for a while.
Hopefully this will give folks considering new import and old iron some things
to watch out for, thing to look for in a good way, and a sense of just what
they are getting into.
If buying new import, I would still buy a 13 inch import lathe before I bought
a 9 inch one, they seem to have some grasp of QC for these larger lathes, and
the included tooling and chucks are a better grade.
I'll have to get on the 9x20 list, no doubt there are some things I can learn,
and perhaps share.
> You are correct; the 9x20 is NOT an SB. And not pretending to be,
> either. Nearly ALL of the 9x20Lathe items you mention are correctable
> pretty easily. I will save bandwidth here and suggest anyone
> interested in the 9x20 lathes come over to the yahoo group 9x20Lathe,
> which I founded.
> P.S. BTW, how much time and money(and experience, either yours, or
> the members of your "club") was spent in reconditioning the 1939 SB?
> Were you lucky enough to avoid needing to plane/grind/scrape the bed?
> Point is, almost ALL lathes are "projects", and the TYPE of project
> one person can handle is different than what another can handle. The
> SB recommendation is a good one, IF the buyer is CAPABLE of
> determining EXACTLY what he/she is getting into...
> The 7x10 and 9x20 import lathes are popular because, although they DO
> have faults; the faults are well documented, correctable (largely),
> and CONSISTENT. You cannot say the same thing about going out and
> getting an old SB. They are all over the map, condition wise... And
> you had better know what you are getting, or you can EASILY get "just
> as" burned. Finally, a GOOD SB beats a "stock" 9x20 every way to
> --- In taigtools@y..., Stan Stocker <stockers@r...> wrote:
> > I have the JET BD920N, same lathe. I bought it new in late '95.
> Tonight is a
> > happy night. I just finished the restoration of a 1939 South Bend
> Workshop C
> > (9 inch swing, about 23 inches between centers).
> > The JET will either be sold or used for work I don't want to do on
> the good
> > lathe. <snip>
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