Live diesel Alsthom BB BB from CFCO

While waiting for a solution to my Polar Deva diesel-elecric generator, I have started a new project: it is the diesel electric built bythomson for the Chemins de Fer du Congo Océan (CFCO). This huge loc (3600 cv) which is a lot for a metric track was built in the late 60's.



I plan to use Aristocraft blocks (60mm between axles, which is a bit short). To keep the longitudinal proportion I reduce the whole longitudinal length in the same proportion; I think it will help in the curves without spoiling tomuch the silhouette of the machine, which will anyhaw be very long (around 75 cm).

I just received my new wheels from Sierra Valley: 37 mm diameter which is thesame reduced proportion as the between axle distance.

I have built a trial chassis before starting the real built up. I plan to power it with a OS 4 stokes FS26 and a Pulso BLDC motor as a starter/generator. The much higher torque should prevent me from the trouble I got on the Polar Deva.

I will tell you more as my project proceeds.

I had not progressed on this project waiting materials to come (and also being on LGB 3060-3061 cars transforms). But now I am nearly set on the motor trucks:






I put some rubber silent blocks between truck and chassis and also between bogies and truck. The deco of the bogie (fictive springs and so on) will be made of PMMA ans bolted in the smaal holes that can be seen on the picture through what we call "entretoise hexagonale" - i do not know the word in english, sorry.

It's a good looking start and an interesting loco. I'm curious to see more.

Very good S-O.  I checked "entretoise hexagonale" on google images, and they are hexagonal PCB standoffs.  An excellent idea.

Best wishes,
Dave.

Just to have an idea of the monster, I made a momentary chassis of MDF. This will also allow me to test curves handling when I receive my LGB curved tracks R3 and R5.



I received my pieces of track. The chassis seems to work nicely on R3 curves, which is quite a relief. Now I can go on developping the project.

It has been quite a longtime since I posted on this topic.

Here are some pictures of the latest progresses.

- the trucks are near completion
the dummy suspension, made of PMMA (except the dummy springs made of electric wire, because I could not find real springs of the right dimension):



the assembled truck:



- the chassis is on the way, made from a 120x40x3 mm rectangular aluminium tube:



- in order to handle curves with a minimum radius R3, I had to design a special coupling. The romm in this part of the model was quite limited, but I finally got through it



now I must find some more brass flat to build the other one!

with the skirt on, one has a fairly good idea of what the model should be



Now I have to work on the mechanical part. I have some problem starting the OS FS 48 motor  I got for the job. I must contact an aeromodelism club where they are familiar to this type of motor. I forgot the idea of a brushless electric motor/generator. Though they have much better performances than brush motor, they are more difficult to handle. So I have ordered, a 12V brushed motor.
I will keep in touch...

Nice work. The bogie parts are looking really good. Is the rubber element connection within the bogies working well or is it to early to say?

It is top eaFly to say. The main problem is that I have no track to make any try.

I have progressed a little on this project.

Here is the engine/motor-generator:



Thereafter, the electrical diagram:



the inverters block:



the big inverter  (N°14 on the diagram) is for reversing the electrical polarity on the motor. The smaller one is for switching front and backlights as well as detecting the neutral point to allow the starter operating. This is done through relays as follows:


The power relays are acted through a Pololu device operated by the RC. The circuit on the bottom of the picture is just a voltage regulator for the extraction fans.


this is what it is when built up.



A small circuit allows the switching of the lights:

A bit disgusted by the problems I encountered on my Polar-Deva (other thread), I tried to progress  on this project.
I made a lot of wiring. I even succeded, after a dozen of trials, programing the Pololu switches so that both will work on the same R/C chanel.

But I fell on a stupid problem: the rubber damping blocks I used for my suspension are much too soft and the loc rolls like a rocking chair! I have to take them apart (which needs some unwiring dure to a bad design of mine!) and do something before going any further. Maybe I will put thin steel leafs across to get some lateral stabilisation while keeping back and forth mobility?

Anyway it will be an heavy model: probably around ten kilograms when finished.