The Bachmann doodlebug is a good model of a 1920's gas electric. The
maker, Electro Motive Corporation, acted as what we would call a systems
integrator today. They purchased engines from Winton, electrical
equipment from General Electric, and contracted out car body consruction
to Brill and others. The machines were built in small batches, and each
batch differed in small ways from the preceeding batch. Later when more
powerful engines become available, Electro Motive will build the first
diesel locomotives, and become the Electromotive Division of GM.
The transmission was always electric. To get a train, even a single
car gas electric train, moving from a dead stop, requires the engine,
running at hundreds of RPM to be coupled to the wheels, running at zero
RPM. No one has ever make a clutch strong enough to put a railcar into
motion. Automatic transmissions had not been invented in the 1920's.
The only workable transmission in that era was electric, an engine
powered generator and street car style traction motors turning the wheels.
David Starr
Actually, not quite true: you're forgetting, for instance, the ill-fated
hydraulic diesels, made by Krauss-Maffei, that SP tried out for a while.
Purely mechanical power transmission. They worked, but the excessive
maintenance required eventually killed them.
Last time I poked around the old SP Locomotive Works in Sac'to, I saw a
K-M parked in the lot with a bunch of other weird pieces of equipment.
Quite a sight.
--
I hope that in a few years it [Wikipedia] will be so bloated that it
will simply disintegrate, because I can't stand the thought that this
SP's KM diesel hydraulics were built in the 1960s, not the 1920s. KM's
locos were built for German conditions -- much smoother track than in
the US, lighter trains, and above all a different attitude to maintenance.
I've seen photos and models of them. Yes, quite a sight.
The Diesel hydraulics worked very well in Europe, particularly Germany
and France. Hydraulic transmission was much lighter than electric so
high horsepower from light locos was/is practical. This was more
important in Europe than the USa as trains there run faster.
In recent years alternators and three phase motors have enabled the
Diesel electric to catch up.
Regards,
Greg.P.
Yes, but the Krauss-Maffei diesel hydralics were built in the 1950's,
where as the doodlebugs were built 30 years earlier, before the
hydraulic transmission had been invented. I always assumed the
Krauss-Maffei's failed to gain market acceptance because the hydraulic
transmission wasn't really strong enough to flow the full power of the
diesel engine thru to the wheels.
After WWII, the Budd company conquered the self propelled rail car
market with their RDC. Those had a pair of smallish diesel engines
mounted under the floor, driving the wheels thru a two speed automotive
style automatic transmission. It was quite noticeable to us passengers
when the transmission finally shifted into high. There was a serious
lurch, then the engine note would die down, and the car would keep
bucketing along at a good clip.
If you ever get back, take some pictures.
David Starr
Yes but RDCs were NOT electric in any way so they do not count.
--
I hope that in a few years it [Wikipedia] will be so bloated that it
will simply disintegrate, because I can't stand the thought that this
thing might someday actually be used as a serious reference source.
Because in its current form, it's not to be taken seriously at all.
- Horst Prillinger (see
http://homepage.univie.ac.at/horst.prillinger/blog/archives/2004/06/0 ...)
Not the case. They were plenty powerful enough; the problems were all
with maintenance, since the US crews weren't used to servicing German
equipment that had lower tolerances than the American-made stuff.
Will do.
--
I hope that in a few years it [Wikipedia] will be so bloated that it
will simply disintegrate, because I can't stand the thought that this
On Mon, 09 Apr 2007 09:56:24 -0700, David Nebenzahl wrote:
Much like the Corvair problem: by the '68 and '69 models they had a better
suspension, and handled much better than almost any other US made car, but
you average Chevy mechanic couldn't keep the engines from leaking oil.
-----------------------------------------------------------------------------------------------
I had a turbocharged 1962 Corvair Spyder. I'm not sure if any mechanic
understood it.
Bill
Bill's Railroad Empire
N Scale Model Railroad:
http://www.billsrailroad.net
Brief History of N Scale:
http://www.billsrailroad.net/history/n-scale
Model Railroad Books, Toys, and Trains:
http://www.billsrailroad.net/bookstore
Resources--Links to 1,200 sites:
http://www.billsrailroad.net/bills-favorite-links
-----------------------------------------------------------------------------------------------
My mother had a '62, but normally aspirated, that I drove a couple times
when I was home on leave. It was a litle anemic, had styling worthy of an
Edsel (gimmicky and uninspired), and did have a pretty crappy swing axle
rear suspension. My brother managed to get the ends swapped around a time
or two.
Nader was right about the handling of that car, although by the time his
book came out it was pretty much corrected, and at the same time ('62) the
major difference between the Corvair's crappy handling and your typical
Ford's crappy handling was which end ran off the road first - it's just
that the average American driver was more frightened of oversteer than
understeer.
-----------------------------------------------------------------------------------------------
Those were the days when GM and Ford mechanics had still to discover
torque wrenches!
Regards,
Greg.P.
Diesel hydraulics date from the early 1930s - petrol electrics from the
1910s.
The German HDs were very successful but the operating conditions were
quite different; short runs with lighter trains at higher speeds.
When Britain tried the same successful designs with similar loads and
speeds the transmissions gave trouble because (?) theruns at higher
speeds tended to be longer.
Diesel hydraulics have also been very successful on heavy shunting
locomotives.
David Starr wrote:
> The transmission was always electric. To get a train, even a single
> car gas electric train, moving from a dead stop, requires the engine,
> running at hundreds of RPM to be coupled to the wheels, running at
> zero RPM. No one has ever make a clutch strong enough to put a
> railcar into motion.
Not true at all, not by any means. There were many petrol-mechanical and
later diesel-mechanical railcars *and* locomotives built and operated in
places like the UK, France, Germany, the rest of Europe, Australia and
Asia, going back to WW1 and before. Hydraulic transmissions for railway
use date to the early 1920s.
Actually Steve, he is correct you are wrong. I have told you before
you need to stop writing on topics you know nothing about. I think
you are doing it on purpose to confuse the group (AKA trolling).
David, don't let him confuse you Steve (:"Mark") does this all the
time. You are correct.
On Apr 10, 1:55�am, Not Mark but really Steve> wrote:
Nope he's not. Here is one example of a gasoline driven motor car with
mechanical transmission built in 1926:
http://www.jernbaner.dk/mhvj/materiel/rhjm4.html
Just so you know, you just responded to *another* well-known troll;
" snipped-for-privacy@aim.com" is the grandaddy of the trolls here. Plus, check
out the list of newsgroups YOU crossposted to. Don't you pay attention?
--
I hope that in a few years it [Wikipedia] will be so bloated that it
will simply disintegrate, because I can't stand the thought that this
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