SOOT IN THE FLUES

L. Woods entitled ‘The Ideal House’. ‘When a man and
his wife bought their house in the suburbs it had everything they
desired space, light, view, design, stability of neighborhood,
location. But after several years the couple began to find fault
with their house, mostly trivial objections that they allowed to
assume importance. So they decided to put their house up for sale,
and then search for their ideal.

‘One day they read an advertisement describing exactly the
kind of a house they wanted. They phoned the real estate man and
discovered the advertisement was one for their own house the one
they were endeavoring to sell!’

Now, each of you sit and ponder this little story. Haven’t
most of us done the same thing in life more than once? Something
inspires us to have or want and we later realize that what we were
seeking, we had all the time. Reminds me of that old saying,
‘The grass always looks greener on the other side of the
fence.’ I’m sure you can identify with what I am speaking
about.

Now on to our letters from some of the IMA family. Wish there
were more, but enjoy these as always.

‘I have just received the March-April issue and noted the
question and reply in your column regarding the possible horsepower
of a prototype engine for which a model exists,’ writes CONRAD
H. MILSTER, 178 Emerson Place, Brooklyn, New York 11205.

‘The reply which you printed was correct as far as it went
but has several factors missing which would frustrate any attempt
to use the formula or arrive at a correct result.

‘Let us start with a model having a cylinder one inch bore
by two inch stroke for the sake of illustration. Our first question
must be what is the scale of the model? Was the prototype 12′ x
24′ or 24′ x 48′ or 6′ x 12′, or some other
size? Doubling the bore of the cylinder increases the piston area
by a factor of 4, so our range from 6′ bore to 24’ bore
will have a 16 fold difference in power output on this point
alone.

‘For argument’s sake let us settle on 12′ x 24’
and see where this leads us. The formula given in your column was
PLAN 33,000. ‘P’ is the average pressure on the piston in
pounds per square inch during the stroke and this opens a whole can
of worms. P is affected by boiler pressure, type of governor and
point of cutoff. An average boiler pressure in the last century
would be 75 to 100 P.S.I., in this century 100 to 150 P.S.I., so
the date of the prototype engine becomes a factor. Let us assume
(one of the many assumptions we must make) it was 100 P.S.I.

‘How does the governor fit into this? Simple! A throttling
governor, such as used on traction engines for example, restricts
the steam flow to the engine cylinder to match the load. Thus there
could be anything from 25 to 100 pounds pressure in the engine
valve chest and again we have a 4 to 1 difference in power. With
this type of governor the point of cutoff is fixed.

‘On the other hand, with a Corliss type valve gear or on an
automatic engine with flywheel governor, the valve chest will have
boiler pressure but the cutoff will vary so that the amount of
steam actually let into the cylinder will equal the work required
at that particular moment. Cutoff can take place at 5-10% of the
stroke or as late as 75-80%. Under either condition the steam
pressure actually in the cylinder at the moment of cutoff, whether
fixed or variable, will drop till the terminal pressure reached at
the end of the stroke when the exhaust valve opens, so you can see
how many variables are involved in obtaining the average pressure.
To confuse the issue even more we must know what the exhaust
conditions were. Did the engine exhaust into a vacuum, atmosphere,
back pressure? For you see, ‘average pressure’ is the
difference between admission and exhaust, not just what is on one
side of the piston. If all these conditions are known, there are
tables available which will give approximate average pressure. Let
us say 50 P.S.I, average for our conditions, again for illustrative
purposes.

‘L is fairly simple, as it is the stroke length in feet
which in our case is 2. ‘A’ is also cut and dried, as we
have settled on a bore of 12′ which gives us an area of about
38 square inches. (We are not taking piston or tail rod areas into
account for this example, for these must be subtracted from total
area as they contribute nothing to the work.)

‘It is starting to go too easily, isn’t it? Our next
factor will go back to muddying the waters, ‘N’ being the
number of strokes per minute (not revolutions, remember). We once
again come back to the type of engine. A true releasing Corliss
might run 60 to 120 r.p.m., a high speed automatic engine from 150
to 300 r.p.m. Again a 5 to 1 ratio, and as each of the above
factors is part of the formula you can see how great a variation in
the end result we can get. Again, for the sake of argument, let us
assume 100 r.p.m. based on the bore/stroke ratio. We do know that
there were practical limits to piston speed in feet per minute so
that the greater bore/stroke ratio, the slower the engine. This
gives us 400 feet per minute, a good average speed.

‘Now we have something to work with, and a moment’s
worth of math gives us (50 x 2 x 38 x200) 33,000 = 23 horsepower.
However, this could also be as low as 10 or as high as 85 within
the conditions we have been discussing.

‘I guess what this all boils down to is that unless all
these factors are known, and in a model this is usually not the
case, it is really anybody’s guess as to what the prototype
horsepower was. In a museum-quality model you could scale off some
of the details and by referring to various builders’ catalogs
come up with an approximate figure. In a copy of the Watts-Campbell
catalog, for example (the last time I will use that word), a
12’x30′ Corliss engine is listed as having a capacity from
24 to 105 horsepower depending on boiler pressure and cutoff, these
being 80 to 120 P.S.I and ¹/₅ to
respectively.

‘Having thus added my bit of confusion to the issue, I will
close by wishing all the folks at Iron-Men Album the very
best!’

ARLEN G. OLSON, P.O. Box 118, Plenty, Saskatchewan, Canada SOL
2R0, has this to say: ‘I ordered your book Steam Engine Guide
and found it to be very interesting and informative. I was
wondering if you have since added any new books on this subject
such as the new reprints of the J.I. Case Steam Engine
Operator’s Manual. I ran across these somewhere but can’t
seem to remember where.

‘I’d also like to see you reprint a complete compilation
of a typical steam engineering course such as the correspondence
course offered by the Clark School of Traction Engineering. I have
the section on valve gears. I enjoy the Iron-Men Album a lot. Thank
you very much. (And thank you for writing, Arlen).

ROBERT PERKINS, 302 Fountain Creek, Palestine, Texas 75801
writes us: ‘In your IMA March-April magazine, which I look
forward to six times a year, I noticed a formula for indicated
horsepower. I have never used that formula. The one I use is
enclosed and worked out as I do it. If I am wrong, I would like to
know about it.

‘Information contained in your magazine is very helpful to
its readers. In the case of a steam engine you have two power
strokes, not one. Will that make a difference in the calculation? I
sure would like to know. I know from reading your magazine that
someone out there knows!

‘The indicated horsepower is obtained by ascertaining the
mean indicated effective pressure in pounds per square inch, the
area of the piston, the length of the stroke in feet and the number
of power strokes per minute. Stated in the form of an equation:

Piston diameter, 10 inches
Length of stroke, 1 foot
Pressure, 150 pounds
Number of strokes per minute, 500

Indicated HP=PALN 33,000 Example: If pressure (P) = 150, piston
area (A) = 78.54 sq. in., stroke length (L) = 12′, and number
of strokes (N) = 500, P+A+L+N = 740.54. Rounding up to 741, 741
over 33,000 = 44.47 HP.

‘We have an excellent gas and steam engine museum in our
local area, and they have suggested that you have a great wealth of
information on the matter I am writing about,’ says CARL E.
ATKISON, 743 Las Palmas Drive, Vista, California 92083.

‘About two weeks ago my wife saw a very brief announcement
on TV of a British automobile which was very modern and
streamlined, powered by a steam engine. She seems to remember that
it was British in origin (wish I had seen the broadcast myself).
Might you have information on the car, or do you know where I might
obtain more detailed information on this matter?

‘I would much appreciate a response on this as I have a
great interest. Inwardly, I have felt that if the steam-powered car
people had had 90 years of research and testing like the internal
combustion engines have had, we would be driving pollution-free
automobiles.’ {How about it, Steam Buddies? Anyone out there
heard of this or know anything about it or where to find some
information?

This comes from K. CHRIS HAMEL, 150 Glenwood Avenue, Jersey
City, New Jersey 07306: ‘Thanks a bundle for the rapid recovery
of the apparent error on the Album of Iron Men Cartoons. Here is a
comic book with a difference! The art work is very well done, and
Mr. Glessner appears to be a fine and talented artist. I’d like
to see some ‘straight’ sketches by him, say like that
excellent Reeves with elevated cab, ‘a landlocked cabin
cruiser!’ You guys are hitting on all four.’

(I must interject at this point, the Iron Men Cartoons is a
great little book, but we will not have any other new ones. Mr. Roy
Glessner died July 5, 1984. He was, as you thought, a fine and
talented artist. Also a brilliant man, a wonderful person and was
loved by many. If you have May-June 1986 Iron-Men Album magazine,
there is a write-up of his death and comments in ‘Soot in the
Flues’ on page 13. Iron-Men Album still carries his magazine as
many folks enjoy it.)

Back to Mr. Hamel’s letter, as he also said, ‘Money well
spent. I’ve considered donating it to a senior citizen home
when I am through with it!’ A good idea!

‘Have you been able to come up with anything on the mystery
tractor I described in the last letter? It definitely had drive
wheels, eight feet in diameter, an apparent six foot ground
clearance, and a wooden cab slightly aft of center. This could not
have been a Case 110 as that had an end cab. I am not an artist but
am enclosing a profile sketch drawn to the best of my memory. This
is based on something I saw over twenty years ago in a magazine,
and sadly was not even captioned correctly. Looking forward to the
magazine and some help on this engine.’ (Don’t forget to
get in touch with Chris if you can help him. He will be grateful
for your letters.

In closing I found some comments and writings on HOME SWEET
HOME: When each lives for the other, and all live for God. (This
ties in a little with the story in the beginning of the column.
I’m liable to make you a bit homesick but now and then that is
good for all of us). A house is built by human hands, but a home is
built by human hearts. He is happiest, be he king or peasant, who
finds peace in his home. Woe to the house where the hen crows
louder than the rooster. I also enclose the following called
‘HOME’. ‘Home: a world of strife shut out, a world of
love shut in. Home: a place where the small are great, and the
great are small. Home: the father’s kingdom, the mother’s
world, and the children’s paradise. Home: where we grumble the
most and are treated the best. Home: the center of our affection,
’round which our heart’s best wishes twine. Home: the place
where our stomachs get three square meals a day and our hearts a
thousand.’ Charles M. Crowe (all from Uncle Ben’s Quote
book by Benjamin R. DeJong.)

Well, that about ends it for this time. Hope you are enjoying
the summer and your hobbies. I had told you my husband was very
sick in February. He is still not back to health, but I thank God
for the progress I have seen. Thanks for the letter, Billy Byrd;
always good to hear from you. Good to hear comments from any
members of IMA Family. Enjoy life as much as you can and keep in
touch with me. Bye, Bye and don’t forget to stop and smell the
flowers. Love Ya!