Why have a motorized 2nd car

[bc6]

Im curious why do Japanese mfgs choose to motorize the second car of a set instead of the engine like the prototypes. The only reason I can think of is that the engine on most shinkasens are low profile and it would be tough to put a motor in it.

[Guest ___]

But that would not explain as to why they do it to everything else that is not a shinkansen.

[bikkuri bahn]

Im curious why do Japanese mfgs choose to motorize the second car of a set instead of the engine like the prototypes. The only reason I can think of is that the engine on most shinkasens are low profile and it would be tough to put a motor in it.

 

Technically, if you're talking about EMUs, having the second car (or any intermediate cars) motorized actually is prototypical.  Many real life EMUs have driving end trailers (i.e. no traction motors).  As for models, it's a good question- perhaps its a marketing decision- maybe casual purchasers/collectors are likely to buy just the driving trailers and the accessible price of a non (M) unit would be attractive.

[Bernard]

Im curious why do Japanese mfgs choose to motorize the second car of a set instead of the engine like the prototypes. The only reason I can think of is that the engine on most shinkasens are low profile and it would be tough to put a motor in it.

 

That is a good question!

When it comes to installing a decoder that besides controlling the motor but also controls the head and tail lights of a train it would be less expensive. In a typical Japanese train you need 3 decoders if the head car had a motor you would only need 2.

Also I find that in most Kato sets it's either the middle car or the second to last car that has the motor and is "pushing" most of the train. I switch the 2nd to last car with the 2nd car behind the engine to give it more of a "pulling" effect. 

[CaptOblivious]

Im curious why do Japanese mfgs choose to motorize the second car of a set instead of the engine like the prototypes. The only reason I can think of is that the engine on most shinkasens are low profile and it would be tough to put a motor in it.

 

Shinkansen do not have "engines" or "locomotives" like the Acela or high speed trains in Europe. Rather, the motive power is distributed among all the cars! Each and every truck in a shinkansen has a traction motor. (In other non-shinkansen EMUs in Japan, about 2/3's of the cars are motorized, and the remainders—including, typically, the cab cars, are trailer cars).

 

So, having the motor in the second or third car is somewhat prototypical…really, there should be a motor in each car :D

 

Practically speaking, since the model will run in each direction, it is a little better to have the motor be as near the middle as possible, so as to be pushing as few cars as possible. First, Rapido couplers, while in general incredibly reliable, work better pulling rather than pushing. Second, it also helps going up inclines, as the inclines are often shorter than the trains themselves, and having the motor car in the middle minimizes the necessary effort (compared to having the motor car at the rear end). (At least in my experience.) Finally, and most importantly :D it allows the end cars to have a fully-detailed cab interior!

[Welshbloke]

It can get even weirder...

 

A series of British EMUs (the 4-CIG/4-BIG/4-VEP and derivatives) had a power car with space for a guard, but no cab. This was either the third or second vehicle in the set depending on direction of travel. In order to minimise the risk of getting stuck on a gap in the 3rd rail, the pickup shoes were mounted on the lead bogies of the two unpowered driving trailers. So the motorised vehicle had no pickups or driving controls!

 

I am currently working on a OO scale 4-BIG (four car unit formed driving trailer-buffet-power car-driving trailer), although as it involves pretty intensive surgery on old Lima MK1 coaches I'm taking my time. The main problem is putting a smooth curve into the new brass sides to match the coach end profile.

[disturbman]

Shinkansen do not have "engines" or "locomotives" like the Acela or high speed trains in Europe.

 

Actually the ICE3/Velaro, the ETR600 and the AGV have distributed motive power. But it's a recent evolution where as the Shinkansens were allways designed with it.

[CaptOblivious]

Shinkansen do not have "engines" or "locomotives" like the Acela or high speed trains in Europe.

 

Actually the ICE3/Velaro, the ETR600 and the AGV have distributed motive power. But it's a recent evolution where as the Shinkansens were allways designed with it.

 

My mistake! Thanks :D

[NGT6 1315]

Shinkansen do not have "engines" or "locomotives" like the Acela or high speed trains in Europe.

 

Actually the ICE3/Velaro, the ETR600 and the AGV have distributed motive power. But it's a recent evolution where as the Shinkansens were allways designed with it.

 

 

But several recent Shinkansen types also include unpowered trailers, do they not?

 

As for non-Shinkansen EMUs - do you have any ideas why many of these actually have unpowered driving trailers and/or 1st class carriages? I could imagine that propulsion noises may not be desired in 1st class carriages (though I personally do not have any problem with that), but why design driving trailers without propulsion?

[clem24]

My opinion is that this has nothing to do with being prototypical. It all has to do with costs. They can design essentially one motor chassis that will work across a whole range of models. Whereas, if they chose the cab car instead, they would have to probably change the chassis frequently to accommodate different headlight/taillight housings, different car lengths (i.e. some end cars have slant noses), different cabs, etc...

[disturbman]

But several recent Shinkansen types also include unpowered trailers, do they not?

 

That's possible. With the recent technology advances in the field of power electronics, you can have small and very powerfull motors. For exemple the ICE 3 just sees half of his bogies motorized. The AGV will also have unpowered bogies, and he is equiped with half the normal amount of bogies.

[bill937ca]

It can get even weirder...

 

A series of British EMUs (the 4-CIG/4-BIG/4-VEP and derivatives) had a power car with space for a guard, but no cab.

 

A non-driving motor was the term for this on the TTC's Glouchester subway cars dating from the 50s.  But they were British built.

[Martijn Meerts]

My opinion is that this has nothing to do with being prototypical. It all has to do with costs. They can design essentially one motor chassis that will work across a whole range of models. Whereas, if they chose the cab car instead, they would have to probably change the chassis frequently to accommodate different headlight/taillight housings, different car lengths (i.e. some end cars have slant noses), different cabs, etc...

 

This is the most likely reason, combined with the fact that if you have a 16 car shinkansen, it's more reliable to push 8 and pull 7 cars, rather than push 15 cars. The Kato M250 has a problem in this regard since it has the motor in the 1st car. Pulling the cars is fine, pushing them can cause problems, especially on curvy parts of a layout.

[bill937ca]

Here are some Nippon-Sharyo spec sheets for various Shinkansens. These diagrams will tell you which cars are powered.

 

N700 http://www.n-sharyo.co.jp/business/tetsudo/pages/jrcn700.htm

 

700  http://www.n-sharyo.co.jp/business/tetsudo/pages/jrc700.htm

 

700 Railstar http://www.n-sharyo.co.jp/business/tetsudo/pages/jrw700e.htm

 

500  http://www.n-sharyo.co.jp/business/tetsudo/pages/jrw500.htm

 

From Tokyu, all axles on E2-1000 are driving axles except the end cars.

 

http://www.tokyu-car.co.jp/eng/rs/rs_e2.html

 

Kinki Sharyo spec sheets

 

N700 http://www.kinkisharyo.co.jp/eng/e_products/sh/e_n700.htm

 

700 Railstar http://www.kinkisharyo.co.jp/eng/e_products/sh/e_700rs.htm

 

700 http://www.kinkisharyo.co.jp/eng/e_products/sh/e_700.htm

 

500 http://www.kinkisharyo.co.jp/eng/e_products/sh/e_500.htm

 

300 http://www.kinkisharyo.co.jp/eng/e_products/sh/e_300.htm

 

Kawasaki Heavy Industries, but no car diagrams.

 

http://www.khi.co.jp/sharyo/pro_final/pro_e.html

[to2leo]

Thanks for the links Bill.  I think Sharyo is my fav train manufacturers...it looks like 80% of the Japanese trains that I like comes from them.

[marknewton]

As for non-Shinkansen EMUs - do you have any ideas why many of these actually have unpowered driving trailers and/or 1st class carriages? I could imagine that propulsion noises may not be desired in 1st class carriages (though I personally do not have any problem with that), but why design driving trailers without propulsion?

 

Economy, pure and simple. If you're not looking to run at Shinkansen speeds, or climb very steep grades, then having unpowered cars is no big deal. And if you want the flexibility of being able to marshal trains into different formations according to traffic requirements, then having a driving trailer allows you to run a two-car train, for example, without having to run the power car around at a terminal.

 

Cheers,

 

Mark.

[westfalen]

The three car EMU's that I drive here in Brisbane have two powered cars and one trailer for the simple reason they don't need three powered cars, motors and the associated equipment cost money. Our 60 class EMU that only has a driving cab at one end and therefore less weight only has one powered truck under the lead car instead of two.

 

I have a theory about the N scale models that the end cars are unpowered so that they can use the same chassis for each end car in a set rather than tool up for one with a motor and one without, and as someone said use the same basic power chassis design for every train, the main difference being the length. As I mentioned in another thread I prefer running my Kato '0' series with the powered car near the rear so the whiplash effect doesn't throw the rear cars off the track on curves, I've never had problems pushing the full 16 cars with the power car even second from the rear, it's almost as if Kato designed the thing for speed.

[Bernard]

I agree a lot has to deal with the cost of making the train.

Westfalen has a point, a lot of Kato models have similar motor chassis that they don't have to retool.

 

One problem I encounter with having the motor car 2nd from the rear is going down an incline. The version of the Kato Narita Express has a knuckle coupler that can easily come apart, there have been a few times I've had 4 cars come zipping down that incline.

[marknewton]

The three car EMU's that I drive here in Brisbane have two powered cars and one trailer for the simple reason they don't need three powered cars, motors and the associated equipment cost money. Our 60 class EMU that only has a driving cab at one end and therefore less weight only has one powered truck under the lead car instead of two.

 

I really should grab a privilege pass and head up to Brisbane. The last time I was up there was before electrification - it was all Evans cars and 1720s.  

 

The trains I crew down here in Sydney run as a permanently coupled motor-trailer pair. But just to be different, the trailers have the cab and pantos, the motor cars have neither. Two M/T pairs make one 4-car set or block, two 4-car sets make one 8-car train.

 

Cheers,

 

Mark.

[Guest ___]

Too early... head spinning..  :BangHead:

[westfalen]

I agree a lot has to deal with the cost of making the train.

Westfalen has a point, a lot of Kato models have similar motor chassis that they don't have to retool.

 

One problem I encounter with having the motor car 2nd from the rear is going down an incline. The version of the Kato Narita Express has a knuckle coupler that can easily come apart, there have been a few times I've had 4 cars come zipping down that incline.

I mainly run the Shinkansen on the club's level N-TRAK layout which also has nice wide curves which helps a lot.

[inobu]

A point I think someone mentioned most JR trains and especially the Shinkansen are bi directional. The other types are uni-directional (has the ability too but normally runs in one direction). Because of this most layouts and routes will be moving back and forth. From the modeling stand point you have to insure that this can be duplicated in a stable manner. There is a fine line to modeling where as limitations are set in order to be profitable and prototypical.

 

Placing the motorized unit in the middle provides a equal weight distribution. In all actually one should only run one motor on a line up because you have no way of load balancing. Some motors run faster than others and instead of it helping to pull the load it just adds to it.

 

I noticed a difference in the gearing on the JF500. (first Shinkasen no knowledge/experience) It is not free spinning. It stops dead in its tracks not sure why but it has to do with the gearing or motor. All of the other types are free spinning in that when you shut off power it roll a bit further. I tested the EH500, DF200, 210, SD70 and SD90 all are free rolling. I pulled out the Sonic 885, stops dead in its tracks.

 

So there is a difference in how they operate and I think it has to do with the way they are designed to push.

 

I bet they have to protect the couplers from stress.

 

Yeah I think thats it, other couplers are spring loaded and a lot more resilient.     

 

Inobu

[Bernard]

A while back on ebay, I found a listing for a 683 Thunder Bird Kato set as "not having a motor in the set". The seller even started that he tested it and it didn't run. It was curious if the seller only tested the head car on a test track. I informed him to check one of the passenger cars for a motor, but he never got back to me. I wasn't sure if in fact I would be bidding on an unpowered set but for the starting price it was listed at, it was worth the chance. No one else bid on the set and when it was delivered to me sure enough the motor was in one of the passenger cars and it ran beautifully. 

[disturbman]

Weird story. Maybe he forgot to put the electricity on. 

[Bernard]

Weird story. Maybe he forgot to put the electricity on. 

Vincent - Most N. American model trains have the motor in the engine or head car, the Japanese sets are different. I can see why he was confused and as a result I made out on the purchase.

There are a couple of other oddities in some model RR engines, some of the Fleishmann and Minitrix Steam engines have the motor in the tender and it pushes the engine along and the wheels and rods turn by friction.