Flywheel / Inertia Effects

[Dave Cooper]

Hi all and Happy new year...

During my last operating session, I was just wondering how to make my loco starts and stops more realistic, less sudden, and less 'jerky'.

I seem to remember one of the main controller manufacturers came out with a panel with separate regulator and brake levers plus an "inertia" setting adjustment ? H & M ? Hornby perhaps ?...

It occurred to me that there are two main approaches :

1. Mechanical - motors with flywheels (would these fit in a typical 009 loco /gearbox ?)
2. Electronic - some sort of capacitor-based system maybe ?

I have yet to read anything about such systems in the smaller scales and /or books on model railway electronics. 

Would be interested in your views, especially "success" stories. I understand the Pendon Museum have cracked the problem...

BTW I now have sprung buffers fitted to my 'road-ends' in case I get it wrong (with rubbish driving !!).

Best regards,
Dave

[engerth399]

I am obviously not up to date with modern controllers as I had thought this was a fairly common feature.  Quite a few years ago (late 1970's I think) Codar had an inertia/brake control which could also, usefully, be turned off if desired.  I have one which still works - its age now attracts the occasional comment.  It, of course, prededes DCC.

Happy New Year to all

Peter

[Hobby]

Gaugemaster still do "simulator" controllers together with their lifetime warranty, link to the panel mounted one which is fine for 009/HOe:

http://www.gaugemaster.com/item_details.asp?code=GMC-U&style=&strType=&Mcode=Gaugemaster+GMC%2DU

[B.Meldon]

If you have the right controller for the chassis then they will start and stop in a realistic fashion by slowly turning the controller up or down.
You should be able to get almost all chassis to do this with a Gaugemaster W or Gaugemaster Combi.
You will not be able to get this with an older rheostat type controller like and H&M.
However the chassis have to be in good order, some older chassis, the Minitrix ones for example, tend to need more power to get them to start moving, also all the Tiny Japanese chassis, with the exception of the Kato Protram chassis are geared too high so again the tend to need more power to get them moving.

Brian Meldon

[Retiarius]

This may be of interest
https://www.world-of-railways.co.uk/news/hornby-launches-app-for-model-railway-control?utm_source=Communicator&utm_medium=Email&utm_content=buttonLink145&utm_campaign=Breaking+News%3A+Hornby+2020+announcements&_ccCt=tBSikgi2NZlMmO45QVs9DXZWoKc5JXH2WhQ1LjFeTwJR8Dq2jEOqIe~gqpRqXqVn

[Hugh Norwood]

2. Electronic - some sort of capacitor-based system maybe ?

If you are thinking about putting a capacitor in each loco as a "flywheel", there are issues in a DC situation:

You'll need a large value to get any discernible effect, which means it will be physically big AND it will be polarised - so it will blow up if you reverse the supply voltage (quite spectacularly). There are ways to make an electrolytic capacitor "ac" but it will reduce the capacitance and increase the volume required to install it.

Similarly you won't want to stick a large capacitor across the track feed...

{As I understand it, the use of "keep-alive" capacitors in DCC means putting a large value cap on what is effectively the dc supply bus local to the DCC chip and it keeps the chip alive rather drive the motor. This gets round the requirement for an "ac-friendly" capacitor}

[Hugh Norwood]

PS, you'd be better off if you could move this thread to the "Electronics and Control" section.
.. where I see you posted something similar a while ago.. :)

[Dave Cooper]

Thanks for the replies folks. Just found an Australian-based system called "CDA" on YouTube that also has separate controls for throttle and brakes and looks quite smooth. (Not sure if this is available in the UK though).

It seems that most 'solutions' are electronic so far...

Hugh: the reason for putting it under "Locomotives" and not "Electronics and Control" is that I was interested to see if there were any 'mechanical' systems as well. Eg I've seen a very effective '0' gauge flywheel-based system in operation at a show. The operators thought this would probably scale down to '00' but weren't sure about '009' - boiler sizes maybe ? Perhaps under a diesel shunter's bonnet ?   

Regards,
Dave

[Hobby]

From the description that Australian one sounds the same as that gaugemaster one I linked you to.

[clayliner]

Minitrains locos and chassis have a 'mechanical' flywheel, don't they (up under the cab roof)?

David.

[Dave Cooper]

Hi Hobby

Thanks for the Gaugemaster link. Yes, I imagine they are similar...

Not really sure how to post a link to the CDA system but the demo is quite interesting for those of us who have never seen such a set-up in operation.

So, here goes:

https://www.youtube.com/watch?v=yhTVEwUiAfo&t=55s

Regards

[Jeff Schumaker]

Minitrains locos and chassis have a 'mechanical' flywheel, don't they (up under the cab roof)?

David.

Yes, they do.

Jeff S.

[B.Meldon]

Minitrains locos and chassis have a 'mechanical' flywheel, don't they (up under the cab roof)?

David.

Yes, they do.

Jeff S.

Yes they do have a flywheel.
However they only have a three pole motor that has precious metal wire wipers in place of brushes.
They do run very well, but this is as much about the gearing as it is the motor and the flywheel.

Brian Meldon

[Hobby]

Not really sure how to post a link to the CDA system but the demo is quite interesting for those of us who have never seen such a set-up in operation.
https://www.youtube.com/watch?v=yhTVEwUiAfo&t=55s

That's exactly the same as the Gaugemaster one (I had one in the past)...

[Dave Cooper]

Is the Minitrains flywheel driven off the back /top of the motor or some sort of gearbox drive ?

I've got something in the workshop that I'd like to experiment with - may try proving it on 00 first of all before going to 009...(Peco "James" ?)

Can anyone suggest a suitable mass for the flywheel as I'll probably have to 'turn down' my lump of brass.

Thanks,
Dave