Linotype Company Hot Metal Thermex Mold Disk –
water cooled — 15 lines per minute
Now THERMEX gives you all of these advantages:
• Continuous high-speed slug casting on one mold
• Faster wide-measure casting of display sizes
• Cooler operation for solid slugs ... less matrix damage
• New back knife for perfect type-high
• Higher mouthpiece temperature aids type face quality
The Thermex is a newly designed water cooled
Linotype mold disk which greatly enhances
efficiency and quality in high speed linecasting.
With the Thermex, slugs can be cast continuously on
one mold at the fastest matrix assembly rates-even
on a tape operated Elektron. The Thermex offers full 4
magazine versatility with a 4 mold disk. No more mold
alternation for cooling.
Even with display sizes the potential speed of tape
operated composition can now be realized.
The cooler operation of the Thermex helps protect matrices from possible type metal accumulations
which could produce damage under vice jaw
pressures. The precise adjustment of mold
temperature to the requirements of each type of work
ensures high typeface quality.
Elektron Introduced in 1964
The Thermex mold disk was developed later – 1966
Production claimed by Mergenthaler for output was
continuous casting on same mold at 14 lines per minute.
Nobody believe it then,
but it accomplished the feat!
Not for just 5 minutes.
We had many runs for 1 hour or more.
Wisconsin Cuneo Press, Milwaukee, Wi. owned two ACE – Automatically Controlled Elektrons.
Quite a challenge. Never a dull moment. Mold cooling hoses intertwined with hydraulic hoses which wound thru wires that kept communication going between 100 or more micro switches, leaf contacts, relays, servo
motors, electric clutches, pumps and one matrix detector light beam. Mold turning and knife block servos
received instructions for settings from a bank of relays located inside a cabinet about the size of a 1940
refrigerator. (55” high x 24” wide x 24” deep) All commands came from TTS punched paper tape via leaf
switches located under the Teletypesetter Operating Unit.
— j merrill - head machinist
A SIGNIFICANT ADVANCE IN SLUG CASTING TECHNOLOGY
The widespread use of tape operated
Linotypes and the popularity of the new Auto
Controlled Elektron have created a need for
increased mold disk heat dissipation, to
permit full utilization of the higher matrix
assembly rates, In response to the new
requirements, Mergenthaler Linotype
Company has developed the Thermex mold disk.
But the importance of the Thermex goes
beyond its application to tape-operated
equipment. Both the efficiency and
operational convenience of practically all Linotypes now in use can be greatly improved
with the Thermex.
Large display type can be cast continuously
on one mold, even at the speed of the new
Auto-Controlled Elektron. The slug is always
solidified completely before the mold is
moved away from the pot mouthpiece; this
insures slug homogeneity and maintains the correct shrinkage patterns for which the matrices have been
designed. Cooler operation also prevents adhesion of type metal to matrices and spacebands, thereby
reducing damage to matrix edges from type metal accumulations. Improved mold temperature uniformity
maintains typeface quality.
PERFECT TYPE HIGH UNIFORMITY
In addition to its unmatched slug casting efficiency, the Thermex offers another great
composing room bonus -significant
reduction of type makeready time.
The allnew "floating" back knife trims the
slug flush with the back of the mold,
maintaining uniform type-high.
Although maintenance of type-high is not
related to heat dissipation, other engineering
problems encountered in the development of
the Thermex disk led to a study of the
mechanical factors responsible for type-high variation.
These factors have now been overcome in
the Thermex through a complete redesign of
the back knife mounting arrangement.
NEW SPRING LOADED BACK KNIFE
With the Thermex disk, type-high variation is
reduced to the vanishing point by trimming
the slug flush with the face of the mold. This
has been accomplished by springloading the
back knife fixture. Solid contact is maintained
between the blade and the mold face, with
ample pressure to insure precise flush
trimming, without danger of abrasion and wear on the mold face.
As the disk revolves from casting to ejection
positions, a system of mechanical linkages to
a cam on the main drive shaft raises and
lowers the knife assembly. The blade is
therefore protected from damage, since it is
brought into contact with the mold face only
when the mold is in the trimming position.
The new spring-loaded back knife eliminates
meticulous manual adjustment of knife-blade
clearance. In addition, type-high variations
requiring correction through time-consuming
insertion and manipulation of equalizing shims, are significantly reduced.
Sensitive water-flow control is provided through a precise
regulatory system. This system consists of a water flow
adjustment screw and gauge, and an automatic valve which
prevents excessive cooling by stopping water flow during
the ejection cycle. A switch is provided to permit continuous
water flow when needed for display point sizes.
Guided by actual equipment performance under the
particular environmental conditions prevailing in his plant,
the Linotype operator determines the best water flow rate for
each kind of work and marks the corresponding float level
on the glass tube indicator of the flow gauge. Thus after a
brief period of use experience, mold temperature can be
accurately set for all types of work.
The start/stop water valve located above controlled the cold water flow thru the top and bottom cooling bars (see below)
clamped onto the molds. When the ACE Elektron received a
stop code (a micro switch didn’t get activated at proper time)
due to a machine malfunction, the timer and memory system
would issue a stop command to the main drive clutch brake,
the water flow valve, and issue hold to the stop magnets on
the TTS (Teletypesetter Operating Unit) which would stop
selecting anymore matrices or mats for assembly,
RECIRCULATING WATER COOLING UNIT
Where water supply is limited, the Thermex disk
may be operated with a re-circulating water cooling unit.
Moreover, this arrangement is advantageous in all
installations, since it offers thermostatically
controlled water temperature. It also allows the use
of distilled or de-mineralized water to insure
trouble-free water circulation.
Special molds are required for use with the
Thermex Mold Disk.
On a Thermex disk, the upper mold clamp is in
the form of a straight, square metal bar instead
of the curved shape found in conventional
disks. This makes it possible to pass the tubing
directly through the clamp, while allowing a
tubing configuration inside the disk that will
tolerate the necessary radial movement of the
clamp. Redesigned molds, with accessory filler
bars to reduce tube flexure in clamping molds of varying point sizes are therefore required. The Thermex
molds are also specially designed to produce standard .918" type-high slugs in conjunction with the flush
trimming back knife. The mold complement for the Thermex disk has been worked out to meet all significant
current slug configuration and point size demand as efficiently as possible.
The Flush Trimming Back Knife!
A ninth wonder of the world!
actually moved up (by cam/roller lever) to the back of the mold
(actually rubbed on the steel mold) as the slug and mold were
rotated by the mold disk back to the eject position. At the
proper moment when the other end of the mold reached the back
knife the cam/roller allowed the back knife to move back, with
help from a back knife return spring) to normal resting position
on the mold adjusting screw. Adjustment between resting knife
edge and back of mold was .010``. The sharp edge had a special
angle ground on it. (Sylben Engeering,
Braidwood, Illinois) created this feature for Henry Cieko, Area Mgr. for Mergenthaler, 531 Plymouth Ct., Chicago for many years.
There was one flaw. Nobody (including
Mergenthaler Linotype) ever tested the system casting 14 lpm for
more than 20 minutes. On extended runs the back knife became very
warm and a nodule (knobs) and sprew (trim from bottom of slug)
would adhere itself to the knife and weld itself to the knife
edge. The next time the knife was crammed against the mold this
obstruction prevented the knife edge from riding the mold by a
thousandth or so inch resulting in type high to vary anywhere
from .918” to .920” or whatever.
It required close
attention from the machinist to “mike” the slugs every 20 minutes
or so and fill in a log sheet showing reading and time. Every 2
hrs. we removed the back knife, (held in place with 1/2” pivot
pin) cleaned cutting edge of knife with a brass rule then applied
something called “preventive metal adhesion”, @ $15.00 a gallon
sold by Mergenthaler. It looked like black liquid graphite.
We also had 2 sets (34 TTS extra thick spacebands each) for
both ACE machines, which were swapped out every 2 hours. The
bands would become very hot and get metal buildup on the casting
edge of the sleeve which then crushed side-walls of matrices.
We would sharpen a piece of brass rule and proceed to remove
the metal buildup from the sleeves. Then the contents in the jar
of “black gold” would get painted onto the casting edge of the
sleeve. And NO. We didn’t get artist pay. (Whatever that was?)
This unit incorporates a 1/3 horsepower Hermetic Compressor, blower cooled condenser, cast
aluminum cooling tank, seven gallon water
storage tank and a valve regulated pump which
permits adjustment of water discharge pressure
to the exact requirements of the slugs being cast.
A thermostatic temperature control maintains
optimum water temperature in the storage tank. A
single re-circulating water cooling unit can
maintain sufficiently low water temperature for
good casting quality with a thermal load for four
molds in continuous operation. A full
complement of safety devices is provided,
including a "Klixon" thermal overload protector
for the compressor and fan motors, a relief valve
to prevent excessive back pressure at the pump
when the Linotype flow control valve is shut off
and a circuit breaker which cuts off all power if
the pump motor is overloaded. An armored hose
is supplied with the Thermex disk for tap water
installations; inlet and outlet hose-connecting
"T" adapters (supplied) will permit the use of standard Mergenthaler hydraulic hose and provide for branch
connections to several disks. Dimensions (approx.): 36” wide x 26” high x 12” deep.