Help for installing them.

Hello everyone!

As some of you might know I have 4 normal, hornby pugs which I want to put a capacitor and a resistor into to slow them down (yes, I know it weakens them) and to make them run better. I just do not know what voltage to use, and how to install them! Any help appreciated! (my dad recently found he had a huge box full of electrical components!) PS, I've attached a photo of the trains.

Thanks!! Darius

That is the first time in my many years in the hobby of installing resistor & capacitor to slow a loco down - normally that is left to a controller.
the old style resistance mat controllers certainly are not the best - transistor controllers are better
like these The Model Shop for Big Imaginations | Gaugemaster   or http://www3.sympatico.ca/kstapleton3/851.HTM

Hi Ron,
I currently have a "el cheapo" hornby single track controller, and eventually want to get a multi-track/handheld controller, but that just isn't in my budget right now! I got the idea from this website: Hornby 0-4-0 speed reduction | Model Railway Forum
Thanks!

Hi Darius

I know nothing about whether extra electrical components would enable better running, but having squeezed a DCC decoder in to two of mine I can tell you there is not much room inside the body.

Think you're better following Ron's advice and saving up for another controller.

You may find a Gaugemaster one (guaranteed for life) at a good price on eBay or the like, where someone has converted to DCC and no longer requires a DC controller.


Ed



 

Hello Darius,
I have drawn a relatively simple throttle that allows you to set the minimum and maximum speed settings of your train. The advantage is that if you need extra power, you can just turn up the maximum speed setting an you won't be permanently stymieing your locos.
How to build this with just the throttle pot(entiometer) is shown on http://yourmodelrailway.net/view_topic.php?id=11601&forum_id=9#p210814. Just substitute a 10k pot for a 1k pot. 
I don't know what your "simple Hornby controller" is apart from what may have come with the Caledonian freight set but if it has a "wall wart" you should be able to connect this throttle to it!

Hope all is well and your package has arrived safely!
Cheers

Trevor

[user=1710]D_Will[/user] wrote:

Hi Ron,
I currently have a "el cheapo" hornby single track controller, and eventually want to get a multi-track/handheld controller, but that just isn't in my budget right now! I got the idea from this website: http://www.modelrailforum.com/forums/index.php?showtopic=21983
Thanks!

that specific thread on MRF was pretty clear in that using diodes, etc to slow things down will certainly slow the motor - less voltage but it is the gearing that really needs to be changed if continuing to use an old style controller - the transistorised version as suggested by xdford would be the way to go.

Thanks Sol.  One of the advantages of the controller as I have drawn it is that you can have control over the full range of the throttle instead of just a half throttle. Even the basic throttle will give Darius (and anyone else reading this) quite a degree of better control as I spoke to a friend with similar locos to Darius' yesterday. 
Cheers
Trevor

Hi Darius,
Sounds like you have Scaletrix motors. Do you want them to have a reduced top speed or better slow running? If these are older models the motor design may not be up to slow running, it will be still 2 speeds, off and full blast, just a slower full blast. Check the start voltage first to see what it takes to get going. I'm remembering 3-4.5v but that could be way off. They run a lot better with a decent pulse width controller rather than a variable voltage controller, and a bit more weight. If you don't have a meter, a 9v battery connected to the track works. 4 AA's will give you 6v, 2 3v, 3 4.5v. +/- a bit of course.
Nigel

Nigel : The motors are Mabuchi or Mabuchi like motors applied to many toys and models but that does not mean that they cannot be controlled properly with the right throttle! 
Darius: Nigel is right that a little more weight should also help. Part of the issue is that the lighter weight on the rail sets up an air gap of insulation with oxide on the wheels etc and it is only when a higher voltage is applied that the insulation is broken down but then the applied voltage is higher and the motor goes off like a jackrabbit.  I suggest you could perhaps load up cavities such as the steam domes with BB shot as a short term measure. Try taping it in first before committing to gluing it in!
Hope this helps!
Trevor

Just had a notification for this, but unfortunately won't ship outside uk.

http://www.ebay.co.uk/itm/Gaugemaster-Series-D-Twin-Track-Controller-OO-Gauge-/400932742219?category=0&buyerid=OT1C29eGPzR21A2qDox8XQ==&emailtemplateid=93960544&sellerid=OF5sKOndb34hqEaeLrAOIg==&refid=store&ssPageName=ADME:B:SEMK:UK:LISTG

Probably the right sort of thing to improve running though.


Ed

Hi Darius, 
Same motors were used in both apparently. A good controller will be much better than an inexpensive one. But then it's almost the same $ as a basic DCC setup with controller if you are looking at a high-end MRC unit. Don't use a UK one, the voltage and cycles are wrong and they are not underwriter approved. The issue is the motor/gear/wheel diameter combination. A combination of high rpm, high gearing and oversized wheels is not optimal for slow speed running. There are fixes for this that work well if you are looking for slow speed control.
Nigel

Hello Darius,
I just tried out my CR 0-4-0 and put a small amount of lead sheet in the top of the boiler - the steam dome was not as big as I thought it would be - and the pickup seemed to be improved and I could get it to "crawl" at about 5 scale miles per hour - high by my standards but OK. The lead was a bit of sheet that was under a motor in an Athearn GP38 before I remotored it yesterday. The top speed set on my controller was low but the control was good. 

I perhaps will try a little more weight later on … I think it will reduce the minimum speed but it should be even steadier than it has shown today!
Cheers
Trevor

Thank you everyone for so much help! I've read and considered everything, but I think I'm going to go with Trevor's throttle, (I have a Hornby Standard Train Controller - R8250). But I still want to put a capacitor in so they are more reliable. That is something a controller cannot fix, but do you guys think that's a good idea? If so, please send me a diagram or some way for me to put it in, and also the votage/microfarad… mircofarad measurement :D!

That is new to me that putting a capacitor into a DC motor - model version - will improve its running !!
To be effective, it needs to be a big capacitance in uf & they usually are electrolytic & thus without reversing the wiring each time the loco changes direction - they will blow up.

Darius, if you can point us to a specific place on the Internet that describes installing a capacitor, it will help us.

Hello Darius,
Sol will probably know much more about this than I so I hope he contributes When I pulled the lid off my 0-4-0, I noted it has a couple of small capacitors I presume for radio suppression but that is not an issue here. 
Capacitors basically smooth out waveforms because when the voltage is down, they discharge and provide an electrical cushion if you will and the voltage will not get to zero. However by filtering the DC, it can also mean that our trains will run worse as the spike helps "push" the motor. 
I notice Sol replied while I was writing this so correct me if I am wrong. A large capacitor will make the train run smoothly once it has started but the starting voltage will be also be higher.
I was also going to test disconnecting the capacitor to see if the motor runs better under my throttle. Starting should be marginally better. Interference is not an issue here in Australia although my layout is in the shed… there was a bit of an issue many years ago when it was inside in what became our daughters bedrooms (the layout was moved twice inside!)  but it was with Athearn motors back in the 80's… my can motors don't have the problem.
Thanks for your show of faith in the throttle design but I wonder what the design of the Hornby R8250 controller actually is? I would suggest that it possibly is a simple transistor controller in itself but a search has failed to find it.
Cheers
Trevor

Darius, as Trevor indicated, the small capacitors already fitted to motors are interference suppression use & in reality, do not improve motor performance.
Yes a large capacitor like 470uf will smooth the input voltage out but then those old motors preferred a slight pulsing/spiking to get them going. Non-electrolytic capacitors which you would need, do not come in big enough uf ( microfarads) to do the job & still fit into locos.

To get a better performance / slow running from Pugs & similar locos/motors, a better controller is required.

The R8250 requires 16v AC input & has a chip inside and I do remember it tends to pulse & some locos did not like it - I guess each motor treats the pulsing differently.

but the Pug motors are not the top of the range either - not designed for shunting by enthusiasts, but mainly running by children.

Hi Darius,

I was going to suggest after all the electrickery discussion that if you want to run Hornby 0-4-0's they can be improved beyond recognition by the Branchlines etched chassis and wheel set kit. The chassis is a quick fold and solder, minimal body work, appropriately sized wheels, and motor and gear ratio of your choice (mine had a 40:1 ratio driven by a Mashima can motor). Plus now it's worth putting a small DCC decoder in. I got mine running at 1 mph (scale). They're in the UK, nice folks, no website, but send an email and they do answer.

Sales@branchlines.com

The next alternative is to rewheel with smaller diameter wheels, although Hornby tend to use some funny axle diameters. I did manage to get a set of Romfords with Triang axles in, but it's a lot of work for the return and it's still the same motor. Check the web for discussions on converting the engine to a 7mm scale narrow gauge one.

The last alternative is weight. Already mentioned but you have to be ruthless. Replace the chimney and dome with brass or white metal castings, go to the local hardware store and get some plumbers lead sheet, and get as much as possible underneath the body over the wheels and along the sides of the body. Add some white metal toolboxes either side on the running plate (hides the motor attachment wires). Fill every nook and cranny with lead shot (from the local hunting store, recycled is fine) and CAA it in place. Add a driver and fireman using white metal castings. Put some chains on the front.

Does your Hornby controller have feedback? If not change it for one that does.

Are the engines Hornby Margate or Hornby China? The Margate ones are better for weight.

Nigel

OK, thanks. I'm not using the capacitor for better running altogether, but I'll explain: I want to put a capacitor into my loco* It is supposed to pick up power from the track, and then in dead spots (especially points) the capacitor powers the locomotive when it cannot get power from the tracks. I never wanted the capacitor for better speeds, that was the resistor's job. Sorry about that!

* I first got this idea from railway modeller volume 66, pages 111-113, called "Staying alive" that talks about putting capacitors into the locos.

Sorry for getting you into this mess!

Ah now it gets clearer !!

I know of "staying alive" but never heard of it for DC, only DCC as it keeps the decoder & motor going for a second or two.

From DCCconcepts site

http://www.dccconcepts.com/vamr/dcc-advice-12-exerpt-b-decoder-standard-connectors-and-stay-alives