Subject: Re: ? about giant lathe (Noble & Lund 96"x30')
From: Robert Bastow <email@example.com>
Date: Tue, 25 Aug 1998 05:57:22 GMT
As big lathes go this is a baby (well mid-range at best) I spent part
of my apprenticeship running a monster 108" swing dual bed ,dual
carriage, roll turning lathe, that would take 48 feet and 90 tons
between centers. Speeds ranged from 1 minute per rev to 12 rev per
minute. It took a crane and about an hour to change the position of
the four face plate jaws. Drive was DC and all controls were on a multi
button pendant...At one rev/ minute jogging speed you learned to true up
a job in two revolutions or less!!
The carriages each had a staircase up about eight feet from ground
level, then there was another staircase up to the top slide which had
about twelve feet of travel and could be set up to cut threads from 8
tpi to about 12" pitch!! One of the fun jobs was screw cutting the cable
ways on eight foot diameter x 14 foot long hoist winding drums. These
were a half round groove for a 1 1/2" dia. cable. Half the drum was
left hand thread the other half right hand pitch. Thats a half round
form tool 1 1/2 inches across cutting full width!..Screw-cutting!! On
some larger (longer) jobs you would have both carriageways machining at
once..that was fun!!!
Tools varied from HSS to carbide inserts and even some early cermets
for chilled iron rolls. Average insert size was 1 1/2" square x 1/2"
thick and held in tool holders up to six inches square. These were in
turn held down by a couple of huge straps with four nuts on each about
six inches across flats. The wrench was about eight feet long and had
to be brought up on the crane. I remember one job on a huge steam
turbine rotor where we strapped the head and turret from a bridgeport
mill onto the tool post to mill a key way.
This type of machine is used daily in heavy engineering works, steel
mills, shipyards arsenals etc. and their work includes the
aforementioned steam turbines, hydro electric generators, steel mill
rolls, gun barrels, monster reduction gears for aircraft carriers, oil
I spent an interesting and informative six months running that machine
and then went on to a 42 foot diameter vertical boring machine and
thence to a 24 foot wide x 48 foot stroke planer. One thing I learned
was to plan the job ahead..mistakes were big and expensive!!
The other thing I learned was that I didn't want to spend the rest of my
life doing that...I still have one shoulder almost an inch lower than
the other and now, in my fifties I hurt all over, every day as a direct
result of the sheer "horse work" of running machines like that while I
was in my teens.