Diesel-Electric Models

[Andrew Pugh]

A true scale 567 or 645 (2-stroke, running on diesel) might be a stretch, but a multi-cylinder diesel should be doable...there are a few (and I mean a few) videos of small scale compression ignition working diesel engines (running on diesel, not nitromethane, and no gloplugs) on youtube.

It wouldn't be beyond the ability of some builders to make a working 16cyl diesel, but probably quite a challenge to make it work as a 2-stroke. Someone needs to commission Find Hansen.

[Steggy]

A true scale 567 or 645 (2-stroke, running on diesel) might be a stretch, but a multi-cylinder diesel should be doable...there are a few (and I mean a few) videos of small scale compression ignition working diesel engines (running on diesel, not nitromethane, and no gloplugs) on youtube.

It wouldn't be beyond the ability of some builders to make a working 16cyl diesel, but probably quite a challenge to make it work as a 2-stroke. Someone needs to commission Find Hansen.

I did kick around the idea of converting the Briggs V-twin to Diesel, as the basic engine has a pretty stout lower end and is well balanced. However, with only four bolts attaching each cylinder head to the block I anticipate intractable head gasket problems will arise with the necessarily high compression ratio. Also, the Briggs is an oversquare design, which typically doesn't work well with compression ignition.

As for building a scale 567, I'm planning on tackling that project in my next lifetime.

[FLSTEAM]

John Boots has an F7 ABBA powered with a V twin driving two Lease Nevell alternators. The alternators charge the battery set. Not sure how many traction motors there are but the engine can run all day pulling heavy loads. I know at least two of the units are powered.

John B.

[Marty_Knox]

I always thought an ALCO 539 would be a good engine to build for a scale Diesel. Inline 6 cylinder, they remind me of an older Chevy 'Stovebolt Six'. With a 12 1/2" bore by 13" stroke I think it would be workable - in 1 1/2" scale it works out to a 1 9/16" bore with 1 5/8" stroke. They were available Turbocharged or naturally aspirated. Oh, and they are a 4 cycle engine.

[LVRR2095]

I used to run a ride on size ALCO diesel back a little over 40 years ago.
Until the turbos got up to speed they made a lot of smoke!

Keith

[Cary Stewart]

RMI models makes a 2 1/2" scale Diesel-hydraulic model of the GE 70 ton engine like the SP Narrow Gage X-1. Several have run at LALS of over the past few years. I wonder if it could be produced with a generator and electric motors? Yes it has a Diesel engine but is VERY quiet.
Cary

[RONALD]

Great discussion, but you guys are neglecting the physics of Scaling Factor!

Thermodynamics does not scale down the way you would like, otherwise every HO gauger would be running a real steaming "Big Boy" on his 4'x8' layout.

Reducing an EMD or any other full size diesel to 1/8th full size may make a great looking small model that will work on air, but once you try burning fuel the Thermodynamics of Scaling Factor has its effect.

[Smokey N Steamer]

I agree. Finding a compromise between authenticity and practicality can be tricky unless you push the right buttons.

I too have dabbled with the idea of a true diesel-electric or gas-electric, and I understand that it will take a lot of engineering to get it to run right.

At least I got the prime mover issue solved, thanks to Kubota's super-mini line of small diesel engines. For a cab unit, like an F-Unit, E-Unit or ALCO PA, their D902-E4B is just small enough to fit inside the shell. For you hood unit guys, I believe if you mount a Z482-E4B so that its output shaft is oriented laterally, it should work out. Fitting the fuel tank, cooling system and exhaust pipes, though, is up to you!

Just thought I'd chime in on my view of the idea.

[Steggy]

For a cab unit, like an F-Unit, E-Unit or ALCO PA, their D902-E4B is just small enough to fit inside the shell.

Did you look at the outline drawing for that powerplant? It's over 21 inches tall, much too large to fit a 1.5" scale loco.

[DanSmo]

Here at the Diamond Valley Railway we have a number of true diesel electric and petrol electric locomotives. They operate just as their full size counterparts with the throttle controlling the power. I can provide more specifics if anyone is interested. Here's a brief overview of a few:

[Andrew Pugh]

Hello Dan, what scale are those locomotives built to?

I've seen a few locomotives from Austrailia at Train Mountain, and they were a fair bit larger than e 1:7.5 and 1:8 locomotives typical in North America for use on 7.25" and 7.5" gauge track. You could even sit in the cab on some of them.

AP

[Smokey N Steamer]

For a cab unit, like an F-Unit, E-Unit or ALCO PA, their D902-E4B is just small enough to fit inside the shell.

Did you look at the outline drawing for that powerplant? It's over 21 inches tall, much too large to fit a 1.5" scale loco.

Well, you could cut a hole in the floor of the unit to make it fit...that's what I had in mind.