Live diesel 2

I would love to make a comment commending your ingenuity, but unfortunately i don't understand a word of what you are saying!!


mikey

I have a clutch bell and fittings which came off my force 15..if you think they would fit, they are yours

Anton, yes please. I'm after a complete clutch assembly, that is shoes, springs, bearings and bell plus flywheel if possible but have a two pin flywheel already if your clutch is a 2 shoe clutch. I also need the spring clip (e clip) that holds the shoes/friction plate to the flywheel and the clip that holds the bell to the shaft - I have a 5mm shaft.
Trying to get a complete Kyosho clutch is difficult as was the carburettor.

Here is a short video of the mini beast running.

These engines are used in 1/10 scale cars and it seems they don't have much rev range or rather much range speed control.
As it's running-in I kept the mixture rich and below about half revs.



The BLDC (brushless DC 3 phase) motor is rated at 910kv this is RPM/volt.
And roughly guessing the speeds that the glo plug engine at idle is about 2,000rpm and half throttle of 10,000 rpm and working out the transmision ratio between the axle shaft 5mm dia and the rubber wheel 25mm dia. shows that BLDC motor rating is correct in that in gives out 1 volt per 1,000rpm approx.

I will need to play around with the transmission ratios between the two.

But it has prospects.

Sorry about the crappy vid quality but it's not easy with 2 hands and 3 things to do.

Well have a look at these photos..all ive got is what you can see...dont know if it can be of use to you?





And i love the CGT trains logo on the video..would love to incorporate that in future diesel vids if you wouldnt mind?

Let me know...

Those bits would be great if you don't mind parting with them.

I'll try and send a high res logo by e mail.

Sure is a noisy thing. Looks like some sort of mad scientist's workshop, with all those wires and stuff about. Great fun.

KleineDicke wrote:

Sure is a noisy thing. Looks like some sort of mad scientist's workshop, with all those wires and stuff about. Great fun.

Don't know about scientist but mad is pretty true.
The noise...and the smoke and smell are all part of it. It's alive!

Anton,

The reason for the large engine has to do with the idle speed. The engine idles at 2,000 which is "fairly slow" for a glow engine. The torque convertor is designed to operate between 3,000 and 10,000 RPM. However in practice I cannot see it going much over 8,000 RPM. This is a Gauge '3' model so all it will ever pull will be carriages and wagons. Here I have to blushingly admit that although I have three completed locos I have no rolling stock for them to pull -if truth be told I have no track laid as yet either!!!

The loco will never move above 45 mph(scale) and the gears are quite robust, "gear grade" nylon is almost as tough as aluminium -with the added benefits that it never needs oiling and it machines easily.

The loco is 68cm long 12cm wide and weighs in at 15Kg (dry). The gearbox gives me 1:90 reduction but with the torque convertor it "slips" thus providing a smoother transition than a direct drive system. I can vary the amount of slip by the level of oil in the torque convertor. I won't bore you with the maths but a torque convertor provides the same torque regardless of the rate of spin -provided you are in the "solidity band" of the fluid used.

The maths show that it would be possible to hit 82MPH (scale) at 8,000 RPM however I think that this would be pushing the "envelope" a bit too much....

regards

ralph

The first start-up is always a bit of a 'shake-down'. My first time about 4 years ago resulted in a well documented serious thumb injury.

Some product news that I found.

1.
Conrad have restarted selling a complete reaady-to-run RC car chassis for 169 euros.
Conrad car chassis

It certainly has possibilities when you add up the separate cost of individual items.

2.
Reliable petrol engines are becoming smaller and cheaper. These are popular with aero modellers and I have been keeping track of developments.

This latest mini:

15cc petrol engine

They also make a 20cc engine; Both engines are less than 75mm wide with a rear mounted carb. so would suitably fit in the body of G scale traction.

This has to be cost effective and better than a 4 stroke glo plug engine.

After dodging the fighting students in my classes at school I managed to sneak in a bit of workshop time and very productive too.

Some cobbling together clutch parts old and new and unsure if it would actually function correctly I connected up the BLDC motor via 1 : 1.5 gearing and.......

It all worked.







It was tested thoroughly for a good hour tonight with positive results.
The BLDC motor is capable of handling the very high revs of the nitro engine.
At about 3/4 throttle it gave out 20 volts.
This was tested with an LGB loco on rollers
The clutch worked perfectly and I was able to stop it with my finger at idle...dangerous!

This Kyosho GX12 engine is very small and a bit twitchy but is getting better each time I run it. The fuel flow needs to be just right, a tad too much and it floods, not enough and it stalls.

The whole set up is very straightforward, no couplings just proprietory gears. No fancy electrics except the diode converter. I don't think a speed controller is necessary unless you gear the motor up and run the engine at lower revs just above idle. A reverse polarity switch is all that maybe required.
The pull starter is adequate and simple with no batteries.
A single channel RC is sufficient.
The whole module could fit in a space 180mm x 80mm.



I can reduce the exhaust noise too with plastic pipe and foam filter. I did some experiments later today after the pics and video and almost completely silenced the engine.

Sounds like a thoroughly successful experiment Dr Hibbs!!

Not really so much of an experiment, that was 4 years a go now, but a rethink based on what has progressed and sharing ideas with others. It's still a bit crazy though and I'm getting addicted to the nitro.....

I think this is the general direction that I will go with live diesel now.

For this particular model I have a brass chassis frame ready and motor bogies.
I need to add radio control, fuel tank and refine the exhaust system and then build a body for which I think I will use 2mm birch ply.
The wood helps with the sound deadening and these .12 engines do scream a bit.

Looking good for a 'post-bac' late June track trial.

Good stuff Carl and well done.

I have come to the conclusion that gears are probably the best way of coupling the two shafts in my design. I have been searching the net for brass gears and am amazed that there does n't seem to be any suitable supplies in the UK via the Engineering sites.. Only thing I can think of is to drive over to Birmingham tomorow to visit a large Nitro car dealership. I dont need a ratio, other than 1 to 1, as the components are well matched but still not happy with those expensive flexible couplings.

Hopefully I am only a few weeks away from having a working chassis but I have been here before a few times.

Bon chance to all those afficted by Live Diesels.

It was a comment from you a while back that set me off looking at gearing.

I source(d) my gears on French e bay,
They are steel, module 1 (1mm pitch) with a 5mm bore which seems to be standard with most geared clutch bell housings. They cost about 6 euros each.

I don't think you could permanently gear the engine and motor without a clutch as this would make remote starting more difficult and maybe impossible with a pull start.

Although there is much less physical resistance in a BLDC motor than a convential DC motor.

Aero engines would need something different as they don't have a pull start so as you say a 1 to 1 gearing may be all right.

I'm now thinking whether a BLDC motor would be able to turn over a nitro engine.......

What I have discovered recently as these nitro engines will start with very little force once they are clean, set up and warm.
Old fuel inside goes quite gummy even in just a few days.

So...
A few drops of special after run oil after a session helps avoid that,
Pre heat with hair dryer.
Turn over engine a few times without glo plug helps loosen things up.
Clean gloplug in alcohol/cellulose thinners because that gets a bit gummy too.
Don't flood engine with fuel.
Pull starter only about 2/3rds out with a few quick strokes rather than trying to start a lawnmower.
Start on slightly rich mixture and lean after.

I think we really must arrange a diesel gathering somewhere, sometime even if we just plan ahead for RailExpo......

Carl, thanks for your extremely helpful synopsis. Nevertheless there is one item I did not understand when you said
""I don't think you could permanently gear the engine and motor without a clutch as this would make remote starting more difficult and maybe impossible with a pull start""
If one is using an ESC and a gearing of 1 to 1 then presumably starting would be no different to starting your Brissonneau. Did you mean a clutch is required if one is not using an ESC or are there other aspects that I have not understood ?
Apologies if this a daft question and thanks in ant.

I was referring just to starting externally with a hand or separate electric starter.
Which from experience has to have the minimum load. The pull starters for example will pull nothing more than the engine itself without breaking.

If you are using and permanent dynamo/starter as I used on the monster then gearing as you described could be a better way than a shaft coupling.

The thing now I realise is that a dynamo is inefficient in generating electricity compared to a BLDC motor.

Carl,

Having built a dynamo I have to agree that they are not worth the effort!!! I had intended to use a stepper motor to power my diesel electric but your use of an outside runner motor appeals to me as it is so simple. And after having hand cut 24, 30Gauge thick Grain Oriented Silicon Steel laminations, to wind onto, to build Gramme Ring dynamo I can only say is:

DON'T DO IT!!!

Pardon the curiosity, the diodes you are using -are they Schottky or simple silicon power diodes? Are you dumping the output into a dustbin sized capacitor and then using a Voltage Reg, (or possibly a jacked up 2N3055 with a zener at the base), to an ESC?

In my surfing I have found a water cooled 500 series outside runner motor that could be useful for my diesel electric and gas turbine electric. The prospect of the latter project has terrified several members of the Gauge '3' Society and G1MRA....

regards

ralph

The diodes are simple standard power diodes rated at about 5 amps I think.
No capacitor and no voltage regulator or esc.

The rectified output from the BLDC was smooth enough to run dc motors without any jerky movement.

I'm still experimenting with this and I would like to get a 'scope and see what sort of wave form comes out plus how much current these motors are capable of producing.

The great thing is that the voltage is linear in proportion to the rpm and seems limitless...!

Also... The output from BLDC motor will drive another BLDC motor direct, unrectified.
And if you reverse the 2 of the 3 phases wires the receiving motor will run in reverse...!

Also... I have started playing about crudely with a 'missing pulse' speed control circuit, by putting 1 of the phases through a simple on/off '555' oscillating timer and ........I will let you know if it works.

I know this is completely off topic but does anyone know how to revive a liithium pollymer battery (3 cell) as i was using it in the hymek the other day and left the switch in the on position overnight and know the battery wont charge, even when using a balance charger. Does anyone have any experience in these kinds of batteries?

Anton I'm sorry to say but an over discharged Lithium Poly battery is to my knowledge finished and irrecoverable. I've seen ads for miracle restorers/chargers however but I don't know if they really work. There are chemical reactions that I believe are irreversible in a discharged battery.

Aha.........more testing.

Now radio controlled with a single channel 27mhz unit using a Playmobil transmitter.





Also gear ratio changed now 1:1.5 so the BLDC spins faster that the nitro engine. This allows the engine to run at a slower speed and the BLDC produces more volts.
The downside is the take up between clutch and BLDC is not so smooth.
I may try a straight 1:1 ratio later on.

The servo is fitted with a very simple pcb divided into two sections and wiper contacts fitted to the servo arm. This acts as a reverser for the DC traction output.

I played around with noise suppression and I can quite confidently eliminate most of the exhaust noise with plastic tubing and gauze.

I also replaced the wooden sandwich base plate with pieces of steel as this helps considerably the cooling.

Here's the latest workshop vid for those (few) interested.



I am waiting for some 85 mm w/b motor bogies from the US to arrive and then I can put a locomotive together based on a Brissoneau at the start of this thread.

I'm also on the look out for another Kyosho GX12 and a similar BLDC motor to make a second unit.

With careful running in these Kyosho motors are quite respectable. Today I didn't use any tools on it. I just connected the fuel, primed it up, connected the glo plug and after a few pulls and a bit of flooding off it went, no stalling and getting smoother every run. Nice........

I would never dare do anything like this, but watching the developments, the effort and the dialogue between specialists is absolutely fascinating.

Power to you all (and hopefully soon to your bogies too)

Can't wait to see it running!

Carl, I managed to get a pair of 19 tooth hardened steel pinion gears from a specialist RC Car shop in Birmingham. They are HPI Racing Part 100918.

Presumably it is possible to mesh gears without the shafts necessarily being the same vertical height providing the shafts are parallel and the required distance apart ????

Incidentally where did you get your gears from.

Yes, as long as they mesh correctly that's the only criteria. I would allow a tiny bit of play in the mesh.

Most of the gears I have seen on RC cars are module 1 (1mm pitch) this seems to be a general standard for clutch bell housings with a gear or gears (some have 2).

I bought mine from a trader on French e bay at about 5 euros each but the packaging on them was from the U.S. originally and marked BSD Racing parts. In French they are called 'pignon'.

I had a look the web and the gears you have bought look pretty much the same as mine.

....Does this mean further developments are in progress....????

I'm building a chassis for mine at the moment. I can't wait for the bogies to arrive so I'm making a simple 4 wheeled chassis with a single powered axle.

Carl Hibbs wrote:

I'm building a chassis for mine at the moment. I can't wait for the bogies to arrive so I'm making a simple 4 wheeled chassis with a single powered axle.

Well I did.....


I'll leave you with this...more details later when I come back from work.