Engine Building in Newark. Introduction of Harris Tabor.
After my return from Philadelphia the first order I received was a very
important one. On the advice of Mr. Holley, the Albany and Rensselaer
Iron and Steel Co. of Troy, N. Y., decided to order from me two engines
for the new roll trains they were about to establish; this being the
first opportunity I had of applying my engine in what proved to be its
most important field. These were a 22×36-inch engine to drive a 16-inch
train for rolling light steel rails, and an 18×30-inch engine to drive
an 8- or 10-inch train for rolling merchant steel. These engines did
not run rapidly; the first was a direct-connected engine making only
75 revolutions per minute; the second made only 112 revolutions per
minute, but was belted to drive the train at twice that speed.
Mr. Corning, president of the company, did not like the slow way in
which the rails were turned out of the former train. I happened to
be standing with him observing this work when he asked a boy why the
billets were not fed to the rolls faster. The boy replied, “Because
the gentlemen at the hooks could not catch them, sir.” Where are the
gentlemen at the hooks to-day, when rails 200 feet long are turned out
of the rolls?
These engines stood near each other, the trains extending in opposite
directions. The battery of boilers was located at a considerable
distance from them. I set between them a vertical steam receiver,
four feet in diameter and twelve feet high. This receiver performed
two functions: it maintained the steam pressure at the cylinders and
separated the steam from the water carried over. This latter was
accomplished by admitting the steam at the top of the receiver by a
pipe extending two thirds of the way to the bottom, draining the water
from the bottom by means of a Nason steam trap, and taking the dry
steam to the engine from the top of the receiver. This was my first
application of this method, which afterwards proved most valuable in
cases of greater importance. These engines were of the highest interest
to me, as their successful running opened the door to that important
field.
While they were still lying on the floor of the shop ready for
shipment, I had an opportunity of submitting them to the criticism of
William R. Jones, the manager of the Edgar Thompson Steel Works, to
whom, as already related, I had sold a small engine and governors for
his large ones. I had not made these engines properly in one respect,
as he pointed out to me that, for rolling-mill uses, they must be made
capable of being run backwards by hand from any position, a requirement
of which I had been ignorant. I soon made the necessary additions to
the valve-gear which enabled this to be done. I never knew how Mr.
Jones came to make this opportune visit, but undoubtedly Mr. Holley
sent him.
I had another visitor before these engines were shipped. It was the
manager of the Laclede rolling mill at St. Louis, accompanied by his
engineer. They had designed a system of driving several trains of rolls
from one engine, the power of which was to be transmitted through
gearing. They were greatly fascinated by the appearance of the engines,
and gave me an order for a large engine on the spot.
This engine afforded me a curious experience. When it was started,
teeth were broken out of the gear at the very first revolution, and I
received a telegram from them telling me of this misfortune and that I
must come to St. Louis immediately and see what was the trouble with
_the engine_. I was too busy to go myself, but Mr. Phillips kindly
permitted his engineer, Mr. Collins, to go in my place. Mr. Collins
took with him everything necessary to expose the defect, whatever
it might be, which we expected would be found in the gearing. Among
other things he had the pattern-maker prepare for him two or three
short pieces of lath about two inches wide and one eighth of an inch
thick; these latter proved to be all that he needed. On his arrival the
proprietors assured him there could be no fault with the gearing, for
they had it made by the most eminent engineering firm in St. Louis.
The members of this firm showed him triumphantly the broken pieces and
directed his attention to the perfect soundness of the metal, as proved
by the fractured surfaces. His first experiment was to whittle an end
of one piece of lath to fit exactly between two teeth of a wheel at one
end of the space. To his amazement he found that this templet would
not fit in any other space around the whole wheel, every one was in
some degree or other too large or too small; neither would the templet
fit in the opposite end of the same space. This one experiment settled
the matter; the engine, to be sure, had broken the gears, because the
larger teeth of the driving-wheels had wedged into the smaller spaces
of the driven wheels. How such work could be produced was a puzzle to
Mr. Collins; as for myself, I have never wondered at any imperfection
in gearing since my experience with Mr. Whitworth’s work. The owners
of the rolling mill applied for advice to Samuel T. Wellman, the
manager of the Otis Steel Works at Cleveland. He gave them the sensible
advice to abandon altogether the plan of driving through gearing, and
to drive each train by a separate engine, directly connected, which
my high-speed engine would enable them to do. This was the first I
heard of Mr. Wellman, with whom I was afterwards to have such pleasant
relations.
While on the subject of gearing I will state a couple of incidents.
One of my first small engines I sold to Mr. Albright of Newark, a
harness-maker. Half of the power of the engine was to be transmitted
to an adjoining building driving a vertical shaft through a pair of
miter gears. It was required that these should run noiselessly, which
at 350 revolutions per minute seemed a difficult thing to accomplish.
I had the gears cut in the best gear cutter I knew of, and fitted
them to run in a lathe, the spindle of the driven gear running in a
frame made for the purpose, and being provided with a friction wheel
and brake. To make sure that the same teeth and spaces should always
come together, I made a prick-punch mark on one tooth and behind the
corresponding space. When started at 350 revolutions they rattled
finely. The resistance of the friction brake was sufficient to make
the points of contact on the teeth mark themselves well in 15 minutes’
running. I then took them down and carefully removed the bright spots
on the surface with a scraper. The next time the noise was more than
half gone, and four successive scrapings by a skillful workman cured it
entirely. There is this encouragement in correcting gearing, that its
subsequent running always tends to improve the truth of the surfaces;
they wear to a more general contact.
One day I had a letter from Mr. Barclay, the miller for whom I had made
my first engine in Harlem, and which I arranged to drive his millstones
by belting. He told me he had moved his mill from Harrison Street to
a building on North Moore Street, New York, and he found there was
something the matter with the engine. (In these cases there is always
something the matter with the engine.) It used to drive three runs of
stones, now it would only drive two, and he burned a great deal more
coal than before. He wanted me to come and see what the matter was.
The moment I opened the door of his mill I knew what the matter was. I
heard the roar of rough gearing and was pretty mad. I told him I hoped
he liked that music, for it cost him more than half the coal he was
burning to keep it up. I gave him a sharp piece of my mind for changing
the system of driving from that which I had provided without consulting
me on the subject. I told him when he threw out his gearing and put the
pulleys and belts back just as I made them, he would find the engine
would give him the same power that it had done for five or six years in
its old location.
[Illustration: ROBERT W. HUNT]
In the first engines which I built in Newark the governor had a more
or less uncomfortable action. This annoyed me exceedingly. It did not
sensibly affect the running of the engine, but was a drawback to the
appearance of the engine in motion. I was utterly at a loss how to
account for it, so I finally determined I would solve the problem by
a comparison of two engines of the same size. One of these was the
smaller engine for the rolling mill at Troy, where the action of the
governor was quite satisfactory; the other was an engine I had made
for the Newark Lime and Cement Company, in which the action of the
governor was very unsatisfactory. After some weeks of comparison I
gave the problem up: I could get no light on the subject. Soon after
I had occasion to go to Troy and found my smaller engine running at
double its former speed or at 224 revolutions per minute. Mr. Robert
W. Hunt, the general superintendent, informed me that they planned to
employ this speed when rolling steel to finish at very small sizes,
which they were then doing for the first time. The action of the
governor which had before been so perfect was now most abominable; the
counterpoise flying up and down furiously between the extreme points
of its action. I told Mr. Hunt that something was hindering the action
of the governor, and asked him if he would have an examination made
and let me know what he found. A few days after I received a letter
from him saying he had found nothing at all, but he added that that
order had been completed and the engine was running at its old speed,
and the governor was working as well as ever. In an instant the truth
flashed upon me; it was the inertia of those polished cast-iron disks
on the rocker-shaft which I had thought so much of that caused all
the trouble. This inertia, increasing as the square of the speed, had
offered four times the resistance to the reversing of their motion
when the speed of the engine was doubled, and the pressure of the link
which was necessary to overcome this resistance held the block fast.
The governor could not move it until it had accumulated sufficient
force by change of its speed; then it moved it too far, and so it was
kept in constant violent motion from one end to the other of its range
of action. I was thoroughly ashamed of myself that when I had made the
subject of inertia a study for years this action should have been going
on so long, the most prominent thing before my eyes, and I never saw
it. I had use enough at once for my new insight as will appear.
The Gautier steel works, which had been located in Jersey City, were
removing to Johnstown, Penn., having formed an alliance with the
Cambria Iron and Steel Company. Mr. Stephen W. Baldwin, then manager
of the Gautier Company, had given me an order for an engine suitable
for driving at 230 revolutions per minute their ten-inch train, or it
may have been an eight-inch. I went to Jersey City and made a careful
measurement of the indicated power required to drive this train. The
engine used was rather a large one, with a large and heavy fly-wheel
running at slow speed and driving the train at this rapid speed by
means of a belt. I found that my 10-inch by 20-inch engine directly
connected with the train would, at 230 revolutions per minute, be
capable of furnishing twice the power they were then using. I built an
engine of that size with a fly-wheel about 8 feet in diameter, shipped
it to Johnstown, and sent George Garraty, my most trusty erecter, to
set it up. I should say that Mr. Baldwin had meantime severed his
connection with the Gautier Steel Company, and it was then in the hands
of parties who were strangers to my engines. I received a letter from
Garraty stating that on his arrival he had found them just about to
send the engine back; everybody about the works had agreed that a man
who sent that little engine to drive that train to roll steel was a
fool. At his solicitation they promised to do nothing until they should
hear from me. I then wrote to the president, Mr. Douglas, stating I had
carefully measured the utmost power which that train had required at
Jersey City, and had furnished an engine capable of supplying double
that power with ease, and I was sure he would run no risk in setting
it up. This he consented to do. While Garraty was erecting the engine
they were making preparations in the mill to stall it if possible.
There was great excitement when it was started; the furnace men worked
like beavers and succeeded in feeding billets to the train twice as
rapidly as ever before, but they could not bring down its speed in the
least. Finally they lowered the steam pressure, but the engine did
not stop until they had brought this down to 40 pounds. Then a great
shout went up, not for themselves but for the engine, which had shown
itself capable of doubling the output of that train, and telegrams
were hurried off to the stockholders of the concern in New York and
Philadelphia to relieve their anxiety. Garraty left that night and
reported himself to me the following morning. After giving an account
of the success of the engine he added: “But the governor is working
very badly; they have not noticed it yet as they have thought only of
the running of the train, but they will.” By a remarkable coincidence
I had that very morning received the letter from Mr. Hunt which had
opened my eyes to the cause of this bad action; the day before I could
not have understood it.
[Illustration: STEPHEN W. BALDWIN]
Within twenty-four hours after my interview with Garraty I had started
for Johnstown, carrying with me two light steel levers to replace those
disks. In that time I had made the drawings and had the levers forged
and finished, joint-pins set and keyways cut, perfect duplicates of
the disks in all their working features. When I told my purpose to Mr.
Douglas he smiled and said for the life of him he could not see what
disks on the rocker-shaft had to do with the governor action. However,
they had not yet started their night shift, so I might have the engine
after 6 o’clock, but it must be ready for use at 6 o’clock the next
morning. I told him that as the change would probably occupy me less
than an hour, I thought I might safely assure him on that point. I
engaged a machinist with the engineer to help me at 7 o’clock in the
evening and amused myself the rest of the day about the mill. The
furious governor action was so irritating I did not stay long in the
engine-room. In the evening we had the disks off and the levers on and
all connected up, ran the engine idle for a few minutes to see that all
was right and I was back in my hotel within the hour, which illustrated
the advantage of working to gauges. I had taken off 29 pounds weight,
that being the difference between the weight of the disks and the
levers. Next morning I went down to see the effect of this change. It
seemed magical. The governor appeared to have gone to sleep, it was not
taking any interest in the activity about it; the counterpoise stood
at about the middle of its range of action, only moving lazily a short
distance up or down occasionally. After calling Mr. Douglas in to see
what disks on the rocker-shaft, with their motion reversed 460 times a
minute, had to do with the governor action, and hearing his expressions
of admiration, I took the next train home. As might be supposed I was
not long in eliminating all traces of this blunder from drawings and
from engines already made.
I had an order from John W. Hyatt of Newark for a 6×12-inch engine to
make 450 revolutions per minute, to drive an attrition mill running
at 900 revolutions per minute, in which he pulverized bones to dust
for manufacturing artificial ivory. This was the highest number of
revolutions per minute that I had ever employed, and perhaps it was
the most absolutely silent running engine that I ever made. Not
long after its completion I had a call from a young gentleman who
introduced himself to me as Harris Tabor. He told me he had invented
a steam-engine indicator which he thought would be superior to the
Richards indicator, as the pencil movement was very much lighter and
would draw a straight vertical line. He said he called in the hope
that I might give him an opportunity to test his indicator on a very
high-speed engine. I told him I thought I could do just what he wanted.
I took him down to Mr. Hyatt’s place where the engine was running with
the indicator rig on it which I had been using; he was, of course,
greatly pleased with this remarkable opportunity. He took a number of
diagrams with his indicator, and they proved to be quite free from the
vibrations which were produced by the Richards indicator at the same
speed. I gave him a certificate that these diagrams had been taken by
his indicator from a Porter-Allen engine at a speed of 450 revolutions
per minute. With these he started for Boston to see Mr. Ashcroft. With
the result of that interview the engineering world is familiar. To
my great regret not one of the diagrams taken at that time has been
preserved either by Mr. Tabor, Mr. Ashcroft or myself, an omission
that none of us can account for. The Hyatt plant was afterwards, I
understood, removed to Albany, N. Y.
I had a singular experience with another 6×12-inch engine which I sold
to William A. Sweet, elder brother of Prof. John E. Sweet, for use in
his spring manufactory in Syracuse, N. Y. Mr. Sweet had two batteries
of boilers set at some distance from each other and at different
elevations; these were connected by a pipe which was necessarily
inclined. About the middle of the length of this pipe a stop-valve
had been introduced, and when this valve was shut the pipe in the
upper end of it was, of course, partly filled with water. My engine
received its steam from the bottom of this pipe below the stop-valve.
The boilers at the lower end were one day overloaded, and while I
happened to be present Mr. Sweet himself opened the stop-valve for
the purpose of getting an additional supply of steam from the upper
battery, but he did not get it. What he did get was a charge of solid
water, which brought my engine to an instantaneous stop from a speed
of 350 revolutions per minute. I was standing near the engine and saw
shooting out from the joint of the back cylinder head a sheet of water,
which at the top struck the roof of the building. On examination it
was found that the steel key of the fly-wheel had been driven into the
wrought-iron shaft almost half an inch and the shaft was bent. The
engine suffered no other injury; the bolts of the cylinder head had not
been strained to their elastic limit, and the nuts did not require to
be tightened. The shaft was straightened, new key-seats were cut for
the fly-wheel, and the engine worked as well as ever--a pretty good
proof of its general strength.
[Illustration: HARRIS TABOR]
I had a couple of funny experiences arising out of my new way of boring
fly-wheels and belt-drums. I sold an engine to Mr. Westinghouse for his
original shop in Pittsburg, before the appearance of the Westinghouse
engine. They erected it for themselves. I received a telegram from
their superintendent, reading: “The hole in your wheel hub is oblong,
what shall we do about it?” To which I wired back: “Put the wheel on
the shaft and drive in the key.”
Another superintendent discovered the same unaccountably bad piece of
work, and did _not_ communicate with me. He did the best he could by
centering the shaft in the hole and filling the spaces on each side
with thin iron scarfed down on each edge. Then the key would not enter
the keyway; so he reduced it until it would. Then the wheel ran an
eighth of an inch out of truth. Then he unstopped the vials of his
wrath and poured out their contents on my devoted head.
I had an order from Mr. Mathieson, manager of the works of the National
Tube Company, at McKeesport, Penn., for two engines, 28 and 32 inches
diameter, with 48 inches stroke. The interest of this story centers in
the former of these engines, which made 125 revolutions per minute. One
day the governor spindle stuck fast in its column, an accident I never
knew to happen before or since, whether caused by a tight fit or for
want of lubrication I do not know. Of course the engine ran away like
mad. Mr. Mathieson and I were in the engine-room; the last I saw of him
his coat skirt was nearly horizontal as he rushed through the door. The
engineer ran to screw down the starting-valve. I thought that would be
too long a process and ran in front of the fly-wheel to unhook the gab.
On the instant, however, I feared what might be the possible effect in
the cylinder of instantly arresting the motion of the admission valves
at an unknown point in the stroke at that speed, and I did not do it.
In a few seconds the engineer had the valve closed, and the engine soon
slowed down. The fly-wheel, which was 20 feet in diameter, did not
burst, and I was confident it would not. I never had an accident to a
fly-wheel, but this was the most severe test to which my fly-wheels
were ever subjected. I have heard of many accidents to fly-wheels, in
which it was evident that they were so carelessly made it seemed as if
they were intended to burst on a moderate acceleration of their speed.
This fly-wheel was necessarily made in halves in order to transport it,
and the joints were so made as to be as strong as the section of the
rim. As the accompanying drawing will show, they were held together by
two steel loops opened out of the solid and shrunk in. It will be seen
that any section of cast iron at this point was equal to the section
of the rim, while the steel loops were stronger. The halves of the hub
were held together by bolts and steel rings.
I sold an engine for a rubber manufactory in Cleveland, Ohio, and some
months after received a letter from the proprietor saying he had been
adding to his machinery and the engine would not drive it all and would
not give its guaranteed power, and he wanted me to come immediately
and see what was the matter with it. On going into the boiler-room I
saw that the steam-gauge showed only 55 pounds pressure. I asked the
engineer why he carried so little pressure, and he told me that the
safety-valve was set to blow off at 60 pounds, which he considered
to be all the pressure a boiler ought to carry; that he had been an
engineer several years on the Lakes, where 60 pounds was the greatest
pressure allowed. I asked the proprietor if he had his boiler insured;
he said he had, in the Hartford Boiler Insurance Company. I said I
supposed that company had an agent in Cleveland. He said: “Yes, and his
office is around the corner on this block, and if you want to see him I
presume I can have him here in ten minutes.” Pretty soon he appeared,
and I said to him: “I understand you have insured this boiler.”
“Yes.”
“Have you made a personal examination of it?”
“I have.”
“What would you consider a safe pressure to carry?”
“One hundred and twenty pounds.”
[Illustration: Mr. Porter’s Fly-wheel.]
“Would you hold it insured at that pressure?”
“Certainly, it would be perfectly safe.”
“Now,” said I to the proprietor, “you will observe that my guarantee
of power assumes a pressure of 85 pounds, and you have no excuse for
not carrying that pressure, and if you do so you will have no trouble;
as for the practice on the Lakes, if you will come to New York we will
show you that on our river and sound steamboats the practice is to
carry only 25 pounds pressure.” He readily agreed to carry the higher
pressure, which he found ample; so I was fooled into going to Cleveland
pretty much for nothing. Afterwards I went there to a better purpose.