I found this very informative page about the New Haven "COMET" of 1935 from a broken website "Mike's Railway History" from the UK. I suggest our fourmer or reader who is younger and healthier than me to save the page as HTML file before it's removed from the web.
According to this page, the Comet was heavier than a railbus or motor railcar at the time but I think it is better to post it here than open a new thread for it, thank you!
THE AMERICAN "COMET"
A Diesel-Electric Express of Remarkable Design
http://mikes.railhistory.railfan.net/r012.html
Jones 3D Modeling Club https://www.youtube.com/Jones3DModelingClub
A steam railcar of Detroit & Lima Northern, circa 1898.
PRR #4689 with rubber-tired truck replaced by Penny's truck.
Source: https://www.facebook.com/photo.php?fbid=2044474248954038&set=gm.10161311783740711&type=3&theater&ifg=1
M636C MidlandMike How were the traction motors connected to those moving axles? Because the movements were comparatively small, the axles had conventional axle hung nose suspended motors and the small angular movement was taken up on the rubber mounts on the nose suspension, just as vertical movement due to suspension travel was accommodated. Peter
MidlandMike How were the traction motors connected to those moving axles?
How were the traction motors connected to those moving axles?
Because the movements were comparatively small, the axles had conventional axle hung nose suspended motors and the small angular movement was taken up on the rubber mounts on the nose suspension, just as vertical movement due to suspension travel was accommodated.
Peter
I thought nose suspension was to accommodate movement pivoting in the vertical direction.
Yes, the Brill 75 railcar has a motor truck which looks like PCC streetcar power truck.
http://satrains.8m.net/brill.html
https://tdu.to/112688.msg
MidlandMikeHow were the traction motors connected to those moving axles?
I believe on the Brill cars they were dummy/trailer trucks. From what I understand of the Volk railway, there are bevel gears and Cardan shaft connection to a separate motor outside the truck.
Jones1945 https://en.wikipedia.org/wiki/South_Australian_Railways_Brill_railcar ' The rear truck of Brill Model 75, reminds me of the tram truck using on the English Electric Balloon in Blackpool.
https://en.wikipedia.org/wiki/South_Australian_Railways_Brill_railcar
'
The rear truck of Brill Model 75, reminds me of the tram truck using on the English Electric Balloon in Blackpool.
It appears that the Brill design was the original, and various tramcar trucks were based on the Brill design.
What may not be obvious at first glance is that the semi-elliptical springs are fixed at the inner end only and have a sliding shoe arrangement at the outer end. Since the springs locate the axle, this provides a steering effect since the load will increase on the outer rail in curves causing the axles to move apart while the reduction in load in the inner rail moves the axles together.
This was considered important for tram cars which operate on very sharp curves.
A derivative of this design was used in Melbourne, Sydney and Brisbane tramways in Australia, becoming a standard in Melbourne.
M636C The South Australian Railways had a number of these for use on low traffic branch lines. They were known as "Brill Model 55" locally. There were larger and heavier "Model 75" cars which were used for some suburban traffic and some main line services. The Model 75 came in two body widths for 5'3" amd 3'6" gauge..... Peter
The South Australian Railways had a number of these for use on low traffic branch lines. They were known as "Brill Model 55" locally.
There were larger and heavier "Model 75" cars which were used for some suburban traffic and some main line services. The Model 75 came in two body widths for 5'3" amd 3'6" gauge.....
Thanks a lot, Peter. It seems the Brill railcar was much popular than I thought! I can understand that not many people think these railcars attractive but from a passenger's point of view, their existence was much better than ceasing of service; from the RRs point of view, they kept serving the people at a much lower operating cost.
South Australian Railways Brill railcar:
Jones1945 http://passcarphotos.rypn.org/Indices/DB4b.htm#PRR4635 PRR #4743, #4744. "Brill "GM68b" express - coach"
http://passcarphotos.rypn.org/Indices/DB4b.htm#PRR4635
PRR #4743, #4744. "Brill "GM68b" express - coach"
MiningmanAlso last link features some overmodulated contraptions for Overmod starting page 458 ' horseless carriages ... '
... of 400 years ago. What a magnificent find! I had no idea these existed, all the sweeter because Cassier's I believe carried some coverage of the high-speed NY-to-Philadelphia electric railroad proposal that was ripening just about this time.
Now this is fascinating! Relevant today.
Also last link features some overmodulated contraptions for Overmod starting page 458 ' horseless carriages'
Thank you very much, Vince and Mike! Those are some very informative materials which help our reader to learn about the historical background of the Autotram as well as Eugene Clark and his enterprise. Imagine Clark's Autotram was a commercial success, it would have made his business empire grew even bigger and became a competitor of Pullman and Budd with actual strength.
https://commons.wikimedia.org/wiki/File:Official_proceedings_(1931)_(14780483343).jpg
Mike finds great things!
Thank you very much for all the information provided, Overmod, Miningman, and Mike. Especially the "1933 Pittsburgh Railway Club proceedings about Autotram". It seems to me that the Autotram project was a high-profile one using a decent engine and car body was designed carefully. It actually achieved something as Overmod stated. The 1930s Cadillac V16 engine probable sound like this:
Overmod The book can apparently still be found on this page (scroll down for the page listing; they cannily mention no publication data, but provide a link to their e-commerce 'shopping cart'. In my opinion, this is $16.95 reasonably well-spent.
The book can apparently still be found on this page (scroll down for the page listing; they cannily mention no publication data, but provide a link to their e-commerce 'shopping cart'. In my opinion, this is $16.95 reasonably well-spent.
Thanks for the link! But no discount code for me as a faithful reader of Overmod?!
Sky Ride in 1933 Chicago World Fair:
Miningman 1933 Pittsburgh Railway Club proceedings about Autotram https://archive.org/details/officialproceedi31rail/page/112
https://archive.org/details/officialproceedi31rail/page/112
Note the discussion of the Budd Company executive regarding Micheline performance, 112-113...
From Mike:
, 1933 Pittsburgh Railway Club proceedings about Autotram
Jones1945The Autotram, an aluminum self-propelled railroad car built by the Clark Equipment Company of Battle Creek in 1932.
Unless I am mistaken, the greatest success of this effort came when parts of the running gear were used for PCCs (and, as Dave Klepper will tell us, experimental New York subway equipment!) I am surprised more people posting about this on the Web haven't figured this out.
The book can apparently still be found on this page (scroll down for the page listing; they cannily mention no publication data, but provide a link to their e-commerce 'shopping cart'. In my opinion this is $16.95 reasonably well-spent.
That's one of the the early-Thirties Cadillac engines. And factory dual exhaust! No problems with smoothness and low-end torque with THAT...
I found this odd duck on the web. The Autotram, an aluminum self-propelled railroad car built by the Clark Equipment Company of Battle Creek in 1932. Powered by a 16-cylinder gasoline engine with a hydraulic clutch, she was displayed in 1933 Chicago World Fair. (Note the light rail under the car)
"the builders claimed the Autotram was capable of 100-mile-per-hour speeds"
https://www.railarchive.net/centprog/autotram.htm
The Cab and the front end reminds me of the design of the flying boat Dornier Do X.
The driver (should I use the term "engineer" here?) tried his best to pretend nothing happened, but you can see the car was shaking like a rollercoaster at high speed.
I guess this is the official rendering of The Autotram:
https://www.flickr.com/photos/paulmalon/13518793944
Patent number #2,051,073 (Clark Tructractor Co) showing the original 12-wheel design.
https://patents.google.com/patent/US2051073?oq=2051073
More pics and detail:
https://www.flickr.com/photos/joes_place/sets/72157608122355729/
Other product by Clark Tructractor Co, Clark Tructractor CT.40 of 1943
Thanks, Overmod. I agree with you that the roof radiators of the Southern Utah car didn't occupy salable interior space; it also didn't make the car looks like a battleship like other doodlebugs. If the cooling effect of it was good, it was a win-win situation. Though I don't know why the radiator of it was ridiculously large, compared to other McKeen Motor Car.
I note there was plenty of room in the engine compartment where both sides of the room had enough space to place a radiator with fans attached to a generator or the motor and create a convective airflow by making two larger grilles on both sides of the engine room. Anyway, the Southern Utah McKeen Car #100 was not a successful example. But I think it looked quite good.
"What's up?...."
At least some of what you observe is a bit different from providing 'sufficient' cooling where there wasn't enough; it involves packaging the cooling where it does not occlude operating vision or deduct from salable interior space. This might particularly apply to the RDC-like roof radiators of the Southern Utah car.
For the longest time, doodlebug people tried to make passive radiators work, where there was no external fan stuff applied to the "coils" and the internal resistance to pumping was kept intentionally minimized. You can see the parallel to this design philosophy in the 'radiators' used on steam locomotive air-brake systems all the way up to the Fifties (where fin-tube designs of some kind began to show up). I suspect very complicated arrangements proportioning cooling to outside temperature were needed in these coil systems, if we can use automatic shutter control on early diesel-electrics as a comparison. Insolation of many of these coils, particularly the ones under the pilot on the Southern Utah car, would have been a relatively minimal source of heat gain compared to what was being rejected to air ... even at the occasionally very high local OATs presumably in that area during operation.
Compare the radiator arrangement on the Budd RDC, which had about the absolute minimum 'cooling system' intrusion into the passenger space (the insulated pipes could be relatively easily accommodated in slightly-thickened car walls, between window openings). Convection up, heat exchangers away from road dirt and mechanical shocks and damage, little chance of leaves and snow blocking air exchange. Compare this with the arrangement, even as amended, on something like the Motorailers with their smaller engines.
Some solutions for cooling. Looked shabby but better than NO service!
Back to America. I wonder how many people still remember this motor car --- The Southern Utah McKeen Car #100, some says it was the largest McKeen Motor Car ever built.
https://mckeencar.com/gallery/s/southern-utah-railroad/
Cooling Coil on the roof and at the front pilot. The temperature of sunlight in Utah must be much lower than other states or countries...
You have pictures there of what I'd think would be the two likeliest 'culprits', so here goes my hypothetical discussion:
The usual 'cheap' way of implementing automotive cooling was to use a mechanical fan on the front of the engine (usually driven by the same belt turning the water pump) which turned proportional to engine speed (and water-pump circulation speed) pulling air through the radiator.
Even minimal forward speed produces the equivalent of ram air circulation through a forward-mounted radiator, and depending on how the ducting around the mechanical fan is constructed this may be many times more effective than 'fan circulation' (as drivers from the era of large American V8 powered cars with air conditioning may remember when in traffic on hot summer days!) It is not difficult to imagine a boxy railcar with small engine hood (or Mack-like radiator behind the engine) where reverse aerodynamic effects either 'spoil' airflow through the radiator or actually counteract what the fan is trying to move in the 'normal' direction. The result might easily be far less actual cooling airflow than expected, or extraction of relatively hot engine-compartment air through the radiator for heat exchange just as peak heat rejection from the engine coolant is most needed...
In automotive applications sustained operation at full throttle 'in reverse' is usually not observed, so it might not be surprising that problems were only observed intermittently in "special" situations. Some of the baroque radiator installations that came to be used on doodlebugs may be related to this issue (particularly those in large boxes completely atop the car with free airflow in both directions).
Not sure about how the cooling issue was solved, but there is an example from the UK to handle such issue:
AEC Q type bus. The engine and the radiator were placed on the right side of the bus, the latter was "facing" the ground. For the railcar in the States, it was not necessary to place the engine on the side, but the radiator with an electric fan could be modified and place it near the car side.
Leyland Olympian, one of the most successful products of Leyland. The radiator is placed at the front, engine at the rear. Not sure if such design ever available or adapted in the States.
Some pics I found from a truck forum. Mack AC Rail Cars:
I didn't know that some of the Mack FCD railbuses were still alive in 2016:
MidlandMikeI read that some rail-buses had trouble with engine cooling (radiator) running backwards. Did they find a fix for that?
The probable definitive solution to this would be an electric cooling fan (or some externally-driven fan or blower if an electric fan weren't cost-effectively available at the time).
Would that the cooling issues with the SPV2000 APU have been as easily solved! (Well, actually they could have been, but the job didn't get addressed in time...)
I read that some rail-buses had trouble with engine cooling (radiator) running backwards. Did they find a fix for that?
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