DISCUSSION
Alcohol firing of
small-scale live steam locomotive boilers is the oldest method of producing
steam in such small mechanisms that is still in current use.
An earlier method of producing steam in builder’s and patent models
involved heating a pig iron block red hot in a coal fire, and then placing the
hot block in a “firebox” constructed in, or underneath, the model’s
boiler. The hot block radiated its
heat through the boiler’s shell and into the water in the boiler.
Usually one block was enough to heat up the boiler to near the boiling
point. When the temperature of the
block was slightly above the temperature of the water the first block was
removed and then replaced with a second red hot iron block.
Now the model was ready to perform the work that it was intended to
demonstrate. Some early gauge three locomotives were “fired” in this
way.
Alcohol firing of
model locomotives of all gauges is most popular in England and its commonwealth
nations. This is because of the long tradition of using alcohol-fueled wicks as
a source of heat in model trains as far back as the end of the 19th
Century. In the United States the early model train manufactures favored
electric power to provide motivation, and so it is still rare to see small-scale
(#1 & “O” gauge) live steam model locomotives here in the States.
You and I know of this facet of the hobby, but I am continuously
surprised to meet long time model railroaders who have never even heard of live
steam power running on 32 and 45-millimeter track.
This discussion of
alcohol fuel will be limited to just that; alcohol as a fuel, and not a how-to
about operating a model locomotive. How-to
information can be obtained by purchasing and reading the pamphlet “An
Introduction to Alcohol Firing” by R. (Roger) Loxley.
ALCOHOL PRODUCTION
There are dozens
of alcohol types produced by industry, but we will only deal with the two most
common types in this discussion. The
first alcohol was produced eons ago by yeasts that fed on composting vegetable
matter. Early mankind entered the
equation when it was discovered that the white coating on grapes was a yeast
that when combined with the juice of the grape would transmogrify into a
fermented beverage; if you could keep the vinegar flies out of it.
At some point it was discovered that grains like barley, wheat, and rice
could also be fermented and so beer making was off to a start.
Honey was fermented into mead. In
some Muslim communities mead may be consumed by believers because it is not the
product of fermenting grapes and grains wherein the prohibition lies.
Distillation was the next step. In
this process the fully fermented liquid is heated so that the alcohol in the mix
boils off and passes through cooling coils where it condenses and collects at
the end of the line. In theory this
distilled liquid is pure ethyl alcohol, known as grain alcohol,
and is identified as 200 proof for federal tax purposes.
Alcohol intended for human consumption is generally cut in half, or more,
with water although there are exceptions.
Alcohol can also
be produced by a process called reduction.
In this process wood is heated in a sealed container without the presence
of oxygen until the wood degrades into charcoal.
Many gasses are given off in this reduction process and they are cooled
through a condensing coil. One of
the liquids collected is methyl alcohol; known as wood alcohol.
Methyl alcohol is 100% poisonous to human beings and its ingestion into
the human body will cause rapid and complete destruction of the human liver and
kidneys.
PURE ALCOHOL CHARACTERISTICS
Both ethyl and
methyl alcohols are clear and colorless liquids with similar physical and
chemical characteristics. Because
of the poisonous nature of methyl alcohol its uses are mostly reserved in the
service of industry as a solvent and as a vehicle for other products.
It is used as a fuel for recreational boat stoves as well as back-packer
type stoves. Shellac is made from
synthetic gums that are dissolved in wood alcohol, and Sterno is a jellied form
used in camping and professional food presentation.
Ethyl and methyl alcohols have different caloric values with ethyl being
the larger at 12,550 BTU per pound and methyl at 10,200 BTU per pound.
Pure methyl alcohol has almost no detectable odor, while pure ethyl
alcohol has a slightly attractive sweet odor.
DENATURED ALCOHOL
There are as many “formulas” for denatured alcohol as
there are manufacturers who provide it to consumers.
Periodically (here in the States anyway) the long arm of the law reaches
out to the producers of denatured alcohol and requires them to alter their
proprietary formulas. When I first
discovered the small-scale live steam locomotive hobby (1995) the denatured
alcohol that I first used was Kleen-Strip’s version called S-L-X.
It was then, as now, available by the quart and gallon can in the paint
department of Home Depot stores throughout the States at about US$8.00 and
change per gallon. In 1995 S-L-X
was made up of nearly equal parts of both ethyl and methyl alcohol with less
than 1% Methyl Isobutyl Ketone (MIK) added to keep the Alcohol, Tobacco, and
Firearms (ATF) branch of the Department of the Treasury happy.
A couple of years ago (1998?) the ATF “asked” Kleen-Strip to alter
their proprietary formula. The
result is that now S-L-X is composed of 80% methanol, less than 20% ethanol, and
MIK not to exceed 3%.
The other big
producer of denatured alcohol in the states is Parks Corporation.
Parks markets denatured alcohol under their own name, and they
manufacture it for resale under “house brands” for other retailers.
One such retailer is True Value Hardware.
I was not able to obtain the proportions of ethyl to methyl alcohol that
Parks uses in their denatured products, but since the ATF is involved is
probably safe to assume that the ratio is very close to the Kleen-Strip formula.
However, there is a heck of a difference in the additives that Parks
inserts into their baseline denatured alcohol product.
First they start off with MIK, as does Kleen-Strip, but then they add
Rubber Solvent (I am unable to identify just what that is) and less than 1% each
of both Toluol and Benzene. I am
not a “tree hugger” and I do not have a problem with additives to products
to improve their value or properties, but I do have a problem if these additives
“seem” to affect the operation of our small scale live steamers; more on
this subject in a later section
.
METHYL ALCOHOL
(pure methanol,
methylated spirits, “methys”)
Methyl alcohol is readily available in the states from
local companies that cater to the “Hot Rod” and racing car market.
It costs around US$3.00 per gallon provided you bring your own can.
Many of these car’s engines operate using straight methyl alcohol as
their fuel of choice. Since
gasoline (petrol), which is the fuel of choice for motorists, contains in excess
of 20,000 BTUs per pound it requires far more pounds (gallons) of methanol to
develop the same horsepower in any given internal combustion engine; especially
if it is a highly modified engine designed to produce gobs of raw horsepower in
the racing environment. In order to
produce this kind of power very large fuel lines (3/8” diameter or better) are
used to transport the methanol from the fuel tank to the fuel system injectors.
The reason most often given for the use of methanol over gasoline in
these racing applications is that the critical temperatures (piston crown,
intake and exhaust valves and seats, and head) are much lower per developed
horsepower when operated using methanol as the fuel.
The key to this logic is that it takes many more pounds (mass) of methanol
to produce the same horsepower, as does gasoline.
The conversion of this liquid fuel (mass) into a flammable vapor, and
then introduced into the engine’s cylinders, efficiently cools the combustion
chamber between power strokes. The
bottom line is that more methanol in pounds or gallons is consumed per unit of
time versus the use of gasoline, but the engine’s critical temperatures are
held in check and the engine’s useful life (though short by domestic use
standards) is extended.
ETHYL ALCOHOL
Ethyl alcohol is available from chemical and scientific
supply retailers in the States. There
is some paperwork involved in its purchase and there is a hefty ATF distilled
spirits tax to be paid (it used to be in the neighborhood of US$10.75/ gal.)
plus the manufacturers and retailer’s markup and then the applicable state
sales tax. By the time all this is
added up the cost of a gallon of 90% neat ethanol will hover around US$ 25 to 30
dollars; not much of a bargain. 100%
pure ethanol is also available, but at a much higher price.
DENATURED ALCOHOL AS
A FUEL (my experiences)
In 1995 I
purchased my first alcohol-fired locomotive; it was an Aster B-1 Baldwin and it
was not a good choice as a first alcohol fired locomotive. Mechanically the locomotive was produced in two versions.
The first 1000 or so units used a four-cup wick burner that was
traditionally mounted between the frames of the locomotive.
Suffice it to say that on this locomotive it was impossible to keep the
front wick lit, and many examples wound up on the mantel or in pieces in an old
shoe box. The remaining 500 units
were modified (I’M guessing at this number since conformation is not
available) to include a stainless steel “belly pan” that completely enclosed
all four wick-cups to protect them from the winds of passage.
I have never operated one of these Baldwin’s so modified, and so I have
no feel for the effectiveness of the “fix”.
After I figured out my particular locomotive I wrote an article that was
published in Steam in the Garden (SitG) to alert others that the locomotive
could be made into a reliable locomotive. I
mention all this as I want to make it clear that the locomotive that I used to
evaluate the three alcohol fuel products that I’m going to write about were
all used in the same, well understood, model locomotive.
As I said earlier my first alcohol fuel was the 50-50 version of S-L-X
from the Home Depot store. As it all turned out this fuel was a blessing to this tyro as
it had no bad characteristics as it was chemically neutral to the copper
wick-cups and the fiberglass and later “mystery materiel” wicks.
Once I had the Baldwin sorted out I fiddled with the wicks length and
tightness (see the article in SitG) until I could achieve reliable (and boring!)
running on my home (flat) track pulling four cosmetically modified Mammod vans.
The locomotive would run all day at 25 to 30 psig only stopping to be
fueled and watered as needed.
I
operated the locomotive through 1997/1998 using the original, to me, fiberglass
wicks. During this period I learned
about the unique care that fiberglass wicks require, and they were well attended
to. In the fall of 1997 I re-wicked
the Baldwin with “mystery materiel”, a more traditional form of wicking, and
then groomed the wicks until the locomotive behaved as before. There are several things that I like about “mystery
materiel”, but the biggest plus is that the tops of the wick strands do not
melt and clot up as does fiberglass. Care
is still required to put the wicks out dead cold at the end of a run lest they
sit and smolder and loose length over time.
Thus, armed with this fine running Baldwin B-1 bunkered locomotive, I
departed for Diamondhead.
