Sheldon History
Sheldon History
Sheldon History
purchased from Monarch by Sheldon when Monarch gave up their beltdriven lathes and went to exclusively gear-head design. However,
Monarch has no record of such a deal, and none of the old-timers
remembered seeing any Monarch prints or drawings at Sheldon Machine.
One old guy recalled seeing Monarch lathe parts spread all over the floor
at the Sheldon factory and sketches being made. Initially, Sheldon
Metalworker lathe parts were made directly from the sketches until
engineering drawings were eventually made. Given that evidence and my
conversations with old-timers, I believe that the Metalworker was copied
directly from the Monarch Junior.
Additionally, when I communicated with Monarch about this issue, they
sent me several pages of documentation and information on the Monarch
Junior. The only difference I could discern between the Sheldon
Metalworker and the Monarch Junior was the name. I have some old
Sheldon pictures that I will have to look at and try to make further
comparisons between the two.
Evolution of the Early Sheldon Lathe Design
As stated, the first Sheldon lathe was the "Metalworker." It had no feed
box, but instead had a set of change gears. There was no apron clutch.
Its spindle ran in cast iron bearings and it was a very low-cost lathe.
Leo Zupan, an Austrian first-generation immigrant mechanical engineer,
was responsible for major design changes and improvements to the
Sheldon Metalworker lathe. These changes included: overhead, and rear,
flat-belt individual motor drives; the two drop-lever feed change box; the
Timken tapered roller bearing headstock; the down-through-the-bed Vbelt spindle drive; the U and E underneath motor drives (which
required a bed and headstock casting change); the bench and pedestal
type support designs to accommodate the new drives; and the telescopic
taper attachment.
1935-1937
Between 1935 and 1937 Sheldon's Machine Shop and Assembly
departments were split. One department was moved to Kilbourn, near
North Ave., and the other was moved to Kilpatrick St. During this time
the L (10-inch), XL (10-inch with a large hole through the spindle, the
S (11-inch), and the M (12/13-inch) lathes were developed through the
tireless efforts of Leo Zupan.
In 1938 George Carolan and the Armstrong brothers purchased the
Sheldon line. The brilliant engineering talent behind Sheldon, Leo Zupan,
went along with the deal. George Carolan, a diverse lawyer, Horace,
Lennox, and Paul were the Armstrong brothers of The Armstrong
1945
After the war, Sheldon redirected its sales efforts toward schools,
universities, laboratories, and industrial consumers. Again, another
addition was made to the south end of the plant, with an eye toward
larger equipment. This addition was brick and returned to steel-beam
construction, with a single- bay, street-level dock facing south into a
parking lot. Through that dock many of the larger pieces of machinery
were brought into the factory.
The 1950's
In late 1953 Sheldon purchased the Sebastian lathe line from Cincinnati
Metalcrafts, Inc. to qualify for the opportunity to quote and build gearedhead lathes for federal contracts. Its interesting to note here that a
group that split away from the group that built The Monarch Machine
Tool Company had formed the Sebastian Machine Company.
To accommodate the Sebastian lathe acquisition, yet another addition
was made to the south end of the plant and set back from Knox Avenue.
It included an over-head crane to handle the assembly and movement of
the heavier Sebastian machines. The larger Sebastian lathe line included
12, 16, 20, and 24 swing machines. Limited production of these
continued while a new Sheldon-Sebastian line was designed.
In the mid-1950s the 13 and 15" Sheldon-Sebastian machines were
added to the line. These were the only Sheldon-designed Sebastian
machines ever built, and the only geared-head lathes that Sheldon built.
The 1960's and 1970's Introduction of the GR and R Models and NC
and CNC
Some people refer to the 1960s and 1970s as the Golden Age of the
American machine tool industry. Sheldon made several interesting
contributions to this period. In the mid-1960's they introduced first the
GR and then the R models, and thereby added a 17-inch machine to
the line. Some people refer to the later R-series Sheldon lathes as gearedhead lathes, but they were in fact belt driven from below with a one- or
two-speed motor or direct driven with hydraulic variable speed motor, or
other combinations. The design on the later R-15 and R-17 machines was
done by a sharp young man who worked for some years under the wing
of Leo Zupan and really made big strides in designing the "R" series,
starting in about 1958, after Leo retired. His name was Don Oddo and he
did a very nice job at the new and innovative design.
At the same time Sheldon was developing a large 30 HP NC 48"x 40"x14"
horizontal mill which was featured at the 1972 Machine Tool Show in
Chicago, at the Stock Yards. At this tool show Sheldon also unveiled a
new Model 1710 CN lathe. Four of the big NC mills were built and used
strictly for Sheldon machine tool production until Sheldon was closed.
Late 1972 saw the introduction of a 2816 NC lathe built on the frame of a
28 x 80 made by Voest-Alpene of Austria and the beginning of the
decline of "L", "XL", "S", & "M" lathe production. Also, by this time the "O"
mill and shaper production were dwindling. However, the demand had
increased for the "R" 13, 15, and 17 lathes. By mid-1975 the
production of all NC lathes had been changed to CNC lathes and they
were offered with 4 station rear turrets and 4 or 8 station front turrets.
1977 saw the introduction of a CNC 2040 vertical mill with 32-tool
automatic tool changer, followed in 1979 by the 3040 horizontal mill
with 2-18" 8-position index tables and a 30-tool automatic tool changer
under CNC control. The table capacity of these machines was 10,000 lbs.
At the same time under development was a CNC 32" 30 HP slant bed
lathe that was to have been in the 1982 Machine Tool Show at McCormick
Place in Chicago.
Sheldon and Other Machine Tool Manufacturers
To my knowledge there was never any hostility between Sheldon and
South Bend, or other machine tool manufacturers, however there was
fierce competition in the field of school, university, and laboratory,
contracts. The competition continued right down the line much like
you'd expect to see in a sporting event. I don't know if Sheldon ever sold
parts or accessories to South Bend but Sheldon, from time to time,
purchased parts and accessories from South Bend. Sheldon had a very
open policy about competition, even at the machine tool shows. Their
policy was that if competition comes to you with questions or for
manufacturing information, and they are up front about who they are,
"tell em what they want to know, but if theyre not being up front don't
tell them anything. I was involved several times taking folks from other
builders, South Bend included, through the Sheldon plant to look at what
was going on. I remember explaining how we were doing things, on the
theory that if they really wanted to know, why make them sneak around
to find out and take a chance that they got bad information. A very
sharp line was drawn at giving out blueprints however.
1982 The End of Sheldon Production
In late 1980 Sheldon was purchased by Acme Cleveland who closed the
Sheldon factory in December of 1982. I guess if I had to give a reason for
Sheldon closing it would be too many big ideas and different directions,
too quickly.
I'll continue to look for Sheldon pictures and documents that may be of
interest, and if any Sheldonlathe Group members have any other
questions, or if I can do anything to help you with your projects, please
let me know.
Respectfully,
John Knox