"Keith Willshaw" wrote in message ...
"alfred montestruc" wrote in message
om...
"Keith Willshaw" wrote in message
...


Hogwash.

Any IC engine that I can give a WWI machine shop the plans for that
does not use late 20th century solid state electronics can be build in
WWI so long as the alloys specified are available. Very little
changed in basic machine shop technology from the lat 19th century
till the introduction of electronic chips.


Apart from the alloys available, lubricants, cooling systems
and ignition systems

The fact is you couldnt get the materials to manufacture the
engine from, most engines of WW1 were cast iron,

Silly them.

the
lubricants were simple mineral oils or vegetable oils,

some vegetable oils are very good lubricants, they are just expensive.

cooling was a major problem , hence the rotary engine
and ignition systems were extremely crude

The issue is were the alloys used in the engine available in the
1914-1918 era, or were reasonable substitutes available. If yes, then
it can be built.

Point of fact, I am very sure that alloys needed either existed, or
reasonable substitutes did.


Evidence please

Artillery gun tubes of that era. They were (obviously) subjected to
high stresses for many thousands of repititions. Obviously the
pressures in a gun tube near the breech during fireing of an artillery
gun are much larger than in an IC engine that has a peak compression
ratio of 10:1 at most.

Imagine if you will I take say a 75mm cannon, hone the bore free of
rifling, then cut it into 6" section to make cylinders for a radial
engine. I can make the engine block out of a ductile iron casting,
the pistons, rods, and shaft from forgings of the same alloy as the
gun tube is made from.

I can then machine fins on the outside of the cylinders and bolt them
to the block. See any showstoppers?

This would not be the way to duplicate the engine of a zero, but the
alloys of the cylinders, crankshafts, pistons and so on cannot have
been vastly superior to those of gun alloys, else one would have seen
a revolution in artillery technology in WWII, and that did not happen,
and little improvement in basic artillery gun tube materials has been
made since the very early part of the 20th century till now. As in
WWI gun tubes are not hopelessly obsolete.





Note that commonly in design of machines where the engineer wants to
allow the potential builder to substitute materials when that
originally specified is not available or the price rises, will spec
the required material properties like hardness, and yield strength and
minimum percent elongation in a tensile test, a range of chemistry, a
specification of acceptable processes (forging, casting, hot or
cold-rolling), and sometimes Charpy impact tests and sometimes more
exotic tests to prove the quality of the material.


None of those tests were in common use in WW1,

Most were available, including tensile testing (quite old) and Charpy
impact testing which became popular soon after the Titanic sank.


steel production
was still more of an art than a science.

Sometimes one goes whole hog and specifies the chemistry of the steel
and tolerences on that chemistry, and all the processes used to make
it from the steel mill on.


They didnt have gas chromatographs in 1914

One does not use a gas chromatagraph to determine the chemistry of
steel, even now. In modern times several methods are used, a popular
one being Optical Emission Spectroscopy, but in those days one kept
track of what one put into the mix and you could also get a read on
Carbon and Sulfer content by combustion analysis using a bomb
calorimeter IIRC, and doing tests on the combustion products.

http://www.materials.co.uk/chem.htm




I work as a mechanical engineer and have designed many machines, and
reviewed the designs of many more.


So have I

Basically your statement is flat wrong, given the plans for the engine
and material specifications for the steels and other materials used in
the engine, which would fit in a shoebox and weigh very little, any
industrial society in WWI era could build them.

Yet first rate engineers like Harry Ricardo were severely constrained
in their engine designs by the technology available.

But if the design and a working example is handed to him?


Some of his designs
could not be manufactured until the 1940's, his sleeve valve engines
required techniques that were still difficult to master in 1939


As I recall the radial engines we are discussing use pretty standard
cam actuated cylinder head valves.