# A new endeavor



## Matt Z (Dec 2, 2009)

Evenin everyone, 

I have been looking into doing something a little off canter. I would like to build an actual "diesel" locomotive. Do miniature diesel motors actually exist? Or is it common to use a motor like one found in an RC car. I want to say that I have seen a project done with an actual diesel motor before. It's been a while since I've seen it though. Any help would be greatly appreciated. 

Thanks all!
Matt


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## takevin (Apr 25, 2010)

One found in a rc car is the same what is used now, so that would not be any different. Too many parts for an actual small diesel. You would have to step up in scale lol.


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## Bob Pero (Jan 13, 2008)

Remember the diesel motor only turns a generator that powers the traction motors that make the locomotive move.


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## Jerry Barnes (Jan 2, 2008)

Quite a few have made 'diesels', using a RC car motor. If you look in the current issue of Steam in the Garden there is an ad by Hyde-Out Mountain Live Steam(740-946-6611 He has live diesel streamliner locos in 3 liveries. Several guys have made them and posted articles here in the past, can't recall who off hand though. I'm sure someone will chime in. In the past, Wada(Japan) made several, including a Pioneer Zephyer.


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## Semper Vaporo (Jan 2, 2008)

It is known as "Live Diesel" and is available in many scales.


I suppose you might be thinking of a V-12 or V-16 engine, but a model airplane engine is a Diesel engine.


Here is one from Hydeout Mountain in 1:32 scale:



I have one and it works quite well. Just noisy and smelly, just like the 1:1 version!


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## Matt Z (Dec 2, 2009)

Wow, too cool! Thanks for the info gentlemen. 

Is this something that anyone has built on their own, or just a few companies manufacturing these? 

I take it that there has to be a signifigant gear reduction from the motor to the drive wheels. Is this done through a gear box, or is it reduced by a simple gear drive? What kind of RPM's do these motors run at, and what is ideal for application at the wheels? 

Matt


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## Semper Vaporo (Jan 2, 2008)

Posted By Matt Z on 30 Nov 2010 06:26 PM 
Wow, too cool! Thanks for the info gentlemen. 

Is this something that anyone has built on their own, or just a few companies manufacturing these? 

I take it that there has to be a signifigant gear reduction from the motor to the drive wheels. Is this done through a gear box, or is it reduced by a simple gear drive? What kind of RPM's do these motors run at, and what is ideal for application at the wheels? 

Matt 


it is a Diesel-Electric, just like the real Diesels on RRs today.

The motor turns a generator to make electricity and the electricity makes a motor spin to drive the wheels.

In most of them, there is a battery that runs the generator as a motor to spin the Diesel engine to get it started and then the battery is removed from the circuit and the generator creates the electricty to recharge the battery and run the motor to make the locomotive go.

In the video you can see that the operator pushes a small toggle switch under the rear of the loco to reverse directions... all it does is reverse the current flow in the electric motor. You can also see the user move a small wire lever under the side of the loco to control the speed of the Diesel engine.


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## Matt Z (Dec 2, 2009)

Interesting, so it's still an electric train just with a motor powering it. 

Has anyone made it so it's strictly mechanical? I am thinking of doing a set of motors each powering its own truck. Each truck will be driven by an "articulating" shaft from the motor. And each axle would have its own gear box. I actually found gear boxes the size of a quarter that have a 120.1 gear ratio. 

I would also have to figure out a forward/reverse system as well. Or just use one truck for reverse and one for forward? 

It would also have to be equipped with a centrifigul clutch in between the motor and gearboxes for idle etc. 

As far as motor control then goes, a set of servos could be installed to control the speed? 

Does this sound feasible? I'm just throwing ideas out there... 

Matt


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## Semper Vaporo (Jan 2, 2008)

Posted By Matt Z on 30 Nov 2010 07:11 PM 
Interesting, so it's still an electric train just with a motor powering it. 

Has anyone made it so it's strictly mechanical? I am thinking of doing a set of motors each powering its own truck. Each truck will be driven by an "articulating" shaft from the motor. And each axle would have its own gear box. I actually found gear boxes the size of a quarter that have a 120.1 gear ratio. 

I would also have to figure out a forward/reverse system as well. Or just use one truck for reverse and one for forward? 

It would also have to be equipped with a centrifigul clutch in between the motor and gearboxes for idle etc. 

As far as motor control then goes, a set of servos could be installed to control the speed? 

Does this sound feasible? I'm just throwing ideas out there... 

Matt 

Very few 1:1 versions of Diesel mechanical drive were built. Usually it was a Gas engine, thus were known as "Gas-Mechanical" locomotives. There were also hydraulic drive, known either as Gas-Hydraulic or Diesel-Hydraulic. There are many built for the 7.5/7.25 inch gauge "ride-on" railroads, especially of the hydraulic type. 
See also: Ralph Brades thread "BR Fell" : http://www.mylargescale.com/Communi...fault.aspx


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## Matt Z (Dec 2, 2009)

You're right. It looks as though I would be making a gas-mechanical locomotive instead. 

That is FAR more complexed than anything I could have ever dreamed up. Very interesting machine and plans to say the least. What size is gauge 3 by the way?


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## TonyWalsham (Jan 2, 2008)

I know of a number of Large Scale "diesel" locos powered small internal combustion engines such as those used by Aircraft, cars and boats. 
RFI is a big problem unless you use 2.4 GHz R/C equipment to control them. 
By far the most successful have been those that controlled loco speed by regulating the engine RPM and *NOT* using an ESC to control motor speed.


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## Spule 4 (Jan 2, 2008)

Carl in France is your man for this, his work is on YouTube and on his own French garden railway forum. 

http://il.youtube.com/watch?v=Ne-iB6EZeHw


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## Matt Z (Dec 2, 2009)

Tony, I'm not too familiar with RC, is an ESC an electronic speed control? How would the motor increase or decrease power when needed? 

Garrett thank you for that info, I'll have to try to get ahold of Carl. 

Matt


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## Scottychaos (Jan 2, 2008)

Posted By Semper Vaporo on 30 Nov 2010 06:32 PM 


it is a Diesel-Electric, just like the real Diesels on RRs today.




well..not exactly the same..
can it really be called a "diesel" if its not actually using a real diesel engine and diesel fuel?
I understand people call the models "live diesel" in the same way we say "live steam"..just for clarity and ease of understanding the concept..but:

Full size diesel locomotives are "diesel-electric" locmotives..
so the models, running on small gas engines, should probably technically be called "gas-electric"..they arent really diesels if they dont have a diesel engine.
my opinion anyway..thoughts on that?

Scot


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## wchasr (Jan 2, 2008)

Scot, 
That is nit picking...model airplane/car/boat engines really run on alcohol and nitro methane (I belive?) and are closer with the glow plug to a diesel engine than a gasoline engine. I believe that they've actually made model airplane engines that ran on actual diesel fuel because that was all the consumers could get? Usually Eastern Europe? 

Chas


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## Scottychaos (Jan 2, 2008)

well no..its not really nit-picking to say a gas engine shouldnt be called a diesel engine!  
thats just a fact.. 

but I dont really know anything about model airplane engines.. 
if they really are "diesel like" then maybe the term "live diesel" is appropriate afterall.. 
I dont know.. 

Scot


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## wchasr (Jan 2, 2008)

Just bustin on ya Scot! Really though it's a glow plug and not gasoline so....whatever. Nitro-electric? I still think it's cool! 

Chas


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## Nutz-n-Bolts (Aug 12, 2010)

Well it's a marine diesel but If this guy made this Surly he could build a 1:32 V-12. The second link refers to the model and the actual workings of this type of engine. By the way Practical Machinist is a great forum too.


http://jalopnik.com/156968/profiles...clen-tomlinsons-mini-triangular-marine-diesel

http://www.practicalmachinist.com/vb/antique-machinery-history/deltic-engine-details-photos-115098/


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## TonyWalsham (Jan 2, 2008)

Posted By Matt Z on 01 Dec 2010 06:49 AM 
Tony, I'm not too familiar with RC, is an ESC an electronic speed control? YES
Hence the initials ESC.


Posted By Matt Z on 01 Dec 2010 06:49 AM 
How would the motor increase or decrease power when needed? 



The speed of the motor is controlled by a servo varying the throttle assembly on the air intake.
There is no need to control the voltage generated with an ESC


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## RimfireJim (Mar 25, 2009)

Posted By Matt Z on 30 Nov 2010 07:11 PM 
Interesting, so it's still an electric train just with a motor powering it. 

Has anyone made it so it's strictly mechanical? I am thinking of doing a set of motors each powering its own truck. Each truck will be driven by an "articulating" shaft from the motor. And each axle would have its own gear box. I actually found gear boxes the size of a quarter that have a 120.1 gear ratio. 

I would also have to figure out a forward/reverse system as well. Or just use one truck for reverse and one for forward? 

It would also have to be equipped with a centrifigul clutch in between the motor and gearboxes for idle etc. 

As far as motor control then goes, a set of servos could be installed to control the speed? 

Does this sound feasible? I'm just throwing ideas out there... 

Matt 
The reason for diesel-electric over straight mechanical drive is that internal combustion engines, particularly diesels, do not have a broad power band. The develop their best performance within a narrow range of rpms. That is why you need a transmission with multiple gears in you car, not just a fixed reduction gear. The generator-traction motor arrangement allows the prime mover to run at an optimal speed.

With your approach you are going to be lugging the engine at low speeds above idle. Centrifugal clutches (without a transmission) work best for applications that go straight from idle to full speed, without much operation in between. Think chain saws and weed whackers.

I think the generator/motor approach would actually be easier, besides being more realistic. Reversing could be accomplished with a simple polarity reversal.


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## Matt Z (Dec 2, 2009)

Thanks again for the info. 

Tony thanks for my daily education on rc electronics, and I still have a long ways to go lol. 

Jim, It makes much more sense when it's laid out right there for you. 

It seems that the generator/motor approach is definitely the way to go, just as the gentlemen mentioned above have created. As soon as the project begins I'll be sure to post progress and will definitely be bugging you all with more questions. 

Thanks a ton 
Matt


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## Andre Anderson (Jan 3, 2008)

Scot,

I have three airplanes with diesel conversions on them, these conversions were made by Davis Diesel http://www.davisdieseldevelopment.com/ so you can make a small diesel electric. The advantages to useing the Davis head on you motor is that you can use a smaller engine with the same power and they tend to run cooler so hiding them in a cowling is easier. They also use much less fuel so I don't have to haul as much weight in to the air with these conversions.


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