Having completed the body and chassis last month there is now a sense of urgency to get the mechanics fitted....and running by October 15.

A long day's work and most of it is in situ and bolted down.







A lot of connecting up to do and I'm waiting for some 3 phase rectifiers to arrive.

This is basically the same arrangement as in the prevous LDP2 project. All the testing was done there so it all should work here. The main difference being the engine. This is a Thunder Tiger .12 a much meatier looking engine (although the same cc) and it seems better quality than the Kyosho.
I'm using a modified aero engine exhaust with a simple coarse foam insert.
Gearing is 14 on the clutch and 15 on the BLDC motor.
The DPDT toggle switch (and adjacent fuse...) is to disconnect the power to the bogies and allow the engine to be run up and tested. It also gives me the option of connecting a small battery pack to the other side so that I can run the loco without the nitro engine.


On another post (Troy's diesel I think) it was discussed about a simple electrical reverser.

This is what I have already done on LDP2 and again with this machine.
This allows the whole operation to be controlled with one RC channel.

A commutator made from pcb divided electrically down the centre.
The red and black wires connected to it come from the rectifier + and -.
The yellow wires go to the traction motor(s) and are soldered to adjustable brass screws acting as wiper contacts.



With the throttle arm in the middle of the servo throw the engine throttle will be at idle.
Which ever way you move the servo it will open the throttle. If the arm rotates clockwise or anticlockwise it will still pull the throttle link.



Throttle open, wiper contacts +/-



Throttle open, wiper contacts -/+.

I have tried alternatives but this is the simplest and most reliable that I can come up with allowing single channel operation.

Ahh,the reversing thing makes perfect sense now
I use the toggle with the whole throw as the throttle.
You should se what I've come up with to get over the problem
It's pure Wallace and Grommit

This latest one of yours is looking very clean and sleek.

All connected up and ready to go....



First run and short track trial.



Run in on 2 tanks of fuel. Engine was very tight and not easy to start at first. Still a few minor points to resolve.

Of course with 2 traction motors to power it needs more rpm and thus more noise and fuel.

I may well disconnect the clutch spring which means the clutch engages almost instantly after starting and less slip.

I will probably change the exhaust for a wooden box as done before. The metal resonates too much.

All in all it works well and that is 3 running locomotives (including Troy's) now built on same principal.

A second test run today. Still a bit of a pig to start, flooding, hydraulic lock etc. but all part of the running-in process.

I changed the exhaust for a baffled wooden box type and still have a nice copper tailpipe.
This muffles the sound and is also cleaner in that it collects more of the spent oil.

The major difference and improvement is that of removing the clutch shoe spring.
The clutch is free on start up but immediately engages afterwards thus allowing lower revs for generating.
This tip was found by accident when the spring broke on the other model and this has successfully been employed on Troy's machine.

In the video the engine is running manually, no radio control on a slightly fast tickover.
This provides adequate volts/current to power the 2 traction motor bogies at a nice scale speed.



Only need to put the body on (it does fit...) and we're just ready for the weekend at St Aubin....

I did find that the engine was running a tad cold but this may improve with body on.

Last preparation and a run before Railexpo. I had hoped to finish off some details like the bogie frame sides and cab interior but these will have to wait now.



It was a bit of a pig to start at first as I had left it for a month with oily fuel in the engine which had congealed and I hadn't used any after-run oil.
Once it warmed up it was fine and ran smoothly at low revs for a good 30 mins on 3/4 of a tank.

I love it Carl, especially the last shot cant wait to see it up close at the expo....its going to be crazy see at least 4 diesels all in one place

Nice video, great model... Not really his locale, but I'll wager that Msr Nuncio Grissoni would love to get behind the controls of that beast!

I haven't done the cab(s) yet but I have lots of space and I shall be having 2 chaps in there as they did in Corsica and in the south of France. One sort of pretending to drive and the other distracting him.

We could imagine that Maestru Grisoni was 'exiled' for a while on the mainland near Toulon pending the vendetta against his cousins.....and he got a part-time job driving up to St Raphaël to collect more liquor.......

For the uninitiated, Mr Grisoni (correct spelling this time!) started life as a Preiser track-worker figure, his full story can be found here: http://www.cgtrains.com/t67-new-starter-on-the-cfc

Carl,

I have just read through all the live diesel posts to get up to speed.
Two things I dont understand

Instead of a 3 phase BLDC could you use a 2 phase BLDC and avoid rectifiying the output to get DC. What are the disadvantages of 2v3 phase.

Can you remember if anyone published a diagram for the 3 phase to DC rectification.

Tx

David, I blagged mine from the fourth post on this page - three pairs of diodes, feed a phase into each pair, then pick up DC on the outer tracks. No drawing I'm afraid. However I made a few spares, so you are welcome to one if it helps.

That's it Dave just as I have done but yours looks neater.

You can buy them cheaply ready encapsulated in a package but they are bigger than making your own on breadboard.

Here's the diagram:



All BLDC motors are 3 phase (to my knowledge).

3 phase BLDC motors are far more efficient than DC motors in converting mechanical force into electrical energy and vice versa.
BLDC motors seem to be able to handle very high revs, they are small, lightweight and comparatively cheap.

It's rather like in cars: the old dynamo versus the alternator.

BTW I'm waiting for a new chassis to arrive and then I'll build another......

Thanks Carl and Dave,

The article I have just read talked about 2 phase and 3 phase BLDC. I will investigate.