I stand by reply 2200, I feel this is a reasonable approach to achieving a surface hardness that would allow adequate wear. I think we both agree that the main area of concern is the fluted shaft. The forces at work on the shaft are very similar to the forces found in a constant velocity joint of a auto. With proper material and methods these joints will usually last 5 or more years.
As far as the technology being old, lets look at fuel cell concept. In 1839 Sir William Grove, a physicist, produced electricity from the reaction of hydrogen and oxygen. In 1959 Thomas Bacon demonstrated the first fully operation fuel cell. Currently are a number of companies and research institutions working on fuel development. Companies are on the brink of being able to produce cheap reliable fuel cells because of improved material methods. Engine technology is not stagnant. Look at the Toyota electric hybrid "Prius". It uses a engine based on the Atkinson cycle. In the 1880's Atkinson was competing in the expanding small engine market against Nicholaus Otto"s. The Otto cycle has been the accepted norm since then. Seems Toyota liked the advantages of the Atkinson cycle. Old technology finding a new home.
Perhaps I am looking at AENG with rose colored glassed, but I like what I see. I will re-iterate that I do not endorse the purchase of the stock, I'm only stating my reason why I believe AENG has a valid product.
Your opinion is greatly appreciated, both sides of the argument need to be explored and debated.
Message 6242271
To: Auric Goldfinger (2197 )
From: cornbread
Sunday, Nov 1 1998 11:12AM ET
All of the following is based on the limited amount of information that is available to me
about the OX2 engine. AENG may have a completely different solution regarding the
wear issue. I can not speak for AENG so the opinions expressed below are mine and
as such they represent my methods of addressing the wear issue.
With out getting into material science 101. Here is my take on how the wear problem is
resolved if a solution by AENG does not already exist.
Hopefully you agree with the following :
Different combination of mechanical properties can be obtained by the varying the
manner in which steels are heated and cooled. I'm focusing on the surface production of
martensite by induction heating and rapid quenching.
The amount of carbon and other metals such as nickel, chromium, molybdenum and
tungsten present in the steel affects the type of martensite produced. Not having access
to any stress / load data, I can not say for certain what the proper combination of metals
will be, however I am confident that this method will produce a suitable wearing surface.
My best guess for now would be the use of a 1060 steel for those parts subject to
wear. Testing will have to be done, if not already done to determine what mix produces
the best results form a wear and economic stand point. If the test results were not
satisfactory I would go to 1080 or a 1095 steel. I have already inquired (via E-mail)
about test data and when it would be published. The reply was that arrangements are
being made to perform a 100 hr load test to and those test results will be published on
the web site. My understanding is that the test results will be performance oriented. I will
send the a company a memo requesting them to consider doing an extensive oil analysis
to determine the amount wear metals present after 100 hrs. I also hope to have them
consider the inclusion of some IR scanning during the test.
Manufacturing in my opinion, is not problem as the parts are machined to near net
tolerances prior to the heat treatment. In order to retain the ductile properties only the
surface is hardened to a depth of approx. 0.005. After hardening, the parts are
tempered, to eliminate any stresses between the harden layer and the remaining steel.
The final piece can be obtained with further machining or grinding.
Correct me if I'm wrong but the mean time between failure of 100,000 miles is your
bench mark for use in the auto industry? I have stated earlier that the engine is a long
way from Detroit. However it is my belief that the current engine would be suitable in
the small engine market. Again, I'm making some large assumptions that AENG does
not have any data at this time to support a MTBF of 100,000 miles perhaps they do.
I'm sure AENG is getting aggravated by my constant inquiries but the response I get
back from AENG leads me to believe that they are addressing these issues and will
bring closure to them in the near future.
Several paper I recommend :
"Hardenability Concepts with Applications to Steel" AIME, 1978.
"Structure and Properties of Engineering Alloys" McCGraw-Hill 1981
"The making , Shaping and Treating of Steel" (9th ed, United States Steel Corp 1971
I apologize about the dated material, but hey I'm an old guy.
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