5 inch 0-4-0 Shunter

Ron,

I know that your engine is electric but even so - going from a design idea to a virtually complete engine in 6 months is pretty good going. I look forward to seeing progress on your traction engine and your shunter. Please keep the pictures coming.

Phil H

Thanks Phil, if I had more shop time, the shunter could have been finished by now..lol

I am a very early riser, I,m usually in the workshop each morning by 5.30am and normally get 3 hours before breakfast, then the happenings of the day take over but most days I get a couple of hours in the afternoon.

I think going with electric does make them much quicker to build though Phil, they are nothing like as complex as steam locos. Even an electric powered scale diesel is relatively simple in comparison. I am a beginner and I am learning but I cant ever see me having the skills that you guys have in building scale steam loco,s, static engines, clocks etc, I think its just beyond me.

So I guess electric models makes things a lot easier, hence the little shunter and traction engine. I can see an end to them, it would be pointless me trying to build say a scale traction engine, it would never get finished and I would get fed up with it, but thats just me.

Ron

Just finishing a few jobs including finalising the wiring to get the loco ready for its first outing/test on the club track..

I am going with mobility scooter batteries as they are a popular choice for powering electric locos/vehicles plus they are said to be true deep cycle batteries..?

Using 2 x 12 volt - 22 amp hour wired in parallel should give me 12 volt 44 amp hour. I have read that for charging it is advised to connect via the negative of one battery and the positive of the other and not via the terminals of just one of the batteries. This should give a balanced charge across the pair where as charging via one of the batteries will not..?

The loco has 4 x 12 volt motors, a pair driving each axle, I have gone with all 4 motors wired in parallel. I did consider the batteries in series (24V) with each pair of motors in series seeing 12 volts each. What put me off was reading on a motor controller manufacturers website that even with identical motors they can have differences in brush timing which can pull down the performance of both motors when in series..?

I know a lot of you guys are very knowledgeable in matters electric and would appreciate your thoughts on the above.

Thanks

Ron

The loco is ready for its first run (well, assuming it does) I still have a few detail jobs to finish but nothing stopping a test, so next weekend is the plan. A picture below of the control panel I have built in with a central power switch and a push horn button below. Top left is the fwd/rev switch with power light below and then the volt/amp meter. The speed control is via the rotary knob on the right but I plan on making up a brass throttle lever with end stops to replace it. Should the running turn out to be ok I will add a lighting set and the switches will live in the space above the throttle.

Will let you know how I get on next weekend, I,ve got my fingers crossed.

Ron,

Sounds good, I am sure it will run as well aa it looks. Going to post some video of it in action? Look forward to seeing it in action.

Paul.

Ron, may I suggest that you fit an additional speed control pot inside set by a screwdriver through a hole to limit the max speed. When children are allowed to drive they only know one setting - full speed. Oh and full reverse instantly so make sure your controller doesn't mind that.
An ddo you have a breakaway chain? and perhaps the power connection through a jack plug that fits a socket in the driving car so power is cut on breakaway.

Edited By Bazyle on 14/04/2019 21:21:34

Hi Paul, I hope it does run ok and yes I will try and get some video of it.

Ron

Hi Bazyle,

When it comes to the grand children driving I will be able to reduce the travel on the throttle lever, I hadnt thought of them switching straight into reverse though so will have to lock that plus I dont have a breakaway chain.

Ron

Should the loco prove to be successful I will add some more detail, mainly to the chassis which will include a set of foot ladders. I thought of making them up from some 1mm sheet brass which I have and soldering them. I have never done any silver soldering and was wondering if my gas canister type blow torch would be ok for small parts. I could soft solder them of course but would like to give silver solder a go if the torch is adequate..?

All sounds sensible to me, but I think the charging issue could only apply if the connections between the batteries had significant resistance.

Neil

There must be truth in that, but depending on the application it may not matter much, maybe! For best performance, the commutators of both motors should be synchronised. If they're not, then both motors will be 'managed' by the commutator position of the other. When the motors are up to speed the effect of misalignment would be a small reduction in power, probably trivial.

Unfortunately starting might be much more troublesome. If the commutators happen to be worst case misaligned and stay that way as the engine tries to pull away the reduced torque when it's most needed could be embarrassing. So I wouldn't wire 2 DC motors in series on a locomotive, or anything else asked to start under load.

How brave are you? With a PWM controller, I'd be tempted to put 24V on 12V motors and manage the duty cycle to avoid overheating the motors. It's risky - matching the motor and battery voltages is safer, and simple solutions are often the best.

Dave

I think you could be spot on there Dave, when I read the manufacturers website they gave an example of the possible problem. They took an identical pair of Graupner 12 volt 900 series motors which when wired in parallel to a 12 volt supply they performed as expected with no faults. However the same two motors wired in series from a 24 volt supply did not perform well and lost most of their torque, that is why I have gone with the 4 motors all in parallel but we will see.

Anyway the little loco is ready for the track, still some bits to do but nothing stopping a test run. I have given it some light weathering to dirty it up a bit and take away the just finished look.

Quite looking forward to taking it to the track and giving it a try.

p.s. Forgot to say 25 kgs AUW which I am hoping will be ok for traction though I am wondering if the suspension springs are a bit on the light side.

Edited By Ron Laden on 17/04/2019 11:09:30

Looks great Ron! Good luck with the first running. Be sure to have a bystander take some video when you are whizzing by.

[This posting has been removed]

The test run of the loco went very well, really pleased with it. A bit of video below with a circuit of the club track, you will have to excuse the video but it was hand held whilst driving and I have no means of video editing so straight from the camera. I will get some off loco footage when I next give it a run. There was no issues at all it has good traction and the club guys estimated 7-8 mph top speed (track speed limit 5mph) I was aiming at 6mph so the gearing/motors has worked out well. It had no problem pulling 3 people even on the 1/100 climbs and I guess it can probably haul 5 adults so should be no problem with me and the VIP passengers..... the two great grand daughters..

Edited By Ron Laden on 24/04/2019 08:46:02

Ron,

Cracking job, well done, you have every right to be pleased. I am sure you and the grandchildren will get a lot of enjoyment from running it. That looks a nice track too.

Paul.

Thanks Paul, I think the two girls will be happy with it, should be fun. I really have enjoyed building it but I always had my fingers crossed that it would turn out ok. Yes the track is nice, not over long about 930 feet but it is in a lovely setting on the edge of Exmoor and only a 25 minute drive away so I am lucky.

Ron

What a great running locomotive Ron! Congratulations! You and the kids will have a great time with it. Enjoyed the video, the track looks great too.

Looks good Ron, hope the traction engine will run as well.

Thanks Jeff/Jason

I think traction engines with the low gearing are ideal for electric drive, though electric is not the norm and they are quite rare beasts. Like yourself Jason I have more than one project on the go and as well as the T/E I have the beginnings of another loco chassis which I made a start on last year so I will be busy. The T/E is longer term though as there is much more work than in an electric loco which tend to be quite simple in comparison.

Ron