009 Society Members Forum

Modelling => Locomotives => Topic started by: rhydddu009 on August 25, 2008, 23:20

Title: flywheels
Post by: rhydddu009 on August 25, 2008, 23:20
Hi,

does anyone have any experience of using flywheels in 009?  I'm thinkibng of adding one to the tiny mashima in my Taliesin kit - is it worth it?  Colin
Title: Re: flywheels
Post by: invercloy on August 26, 2008, 09:25
Hi Colin,

I've got one on one of the Roco 0-6-0 tender locos with outside frames, that runs superbly and when i put my Zimo decoder in it it can only get better.  At present it accelerates and decelerates nice and smoothly.  I think it would be worth it.  If i remember right Neville from N Drive Productions had some flywheels for sale at ExpoNG last year that fitted onto Mashima motors if you don't have the use of a Lathe.
Title: Re: flywheels
Post by: Darren Hedges on August 26, 2008, 18:49
If you can fit a fly wheel it really is a must, you will certainly notice a difference in running quality. Try to fit the biggest you can get in, and don't forget you can increase the mass of the fly wheel and therefore it's effectiveness, by increasing the length as well as the width.
Title: Re: flywheels
Post by: vulcan on August 27, 2008, 11:26
Yes it does work well - Mainly Trains sell some small(ish) flywheels for 1.5mm shafts - I've fitted one to a 10/16 without any problems using threadlok.
Title: Re: flywheels
Post by: rhydddu009 on August 27, 2008, 15:01
thanks.  In just reading 'loco kit chassis construction' by Iain Rice I note that he states about the mashima 1220 (or similar 1224) that...

"due to the low-revving nature of the motor, there's precious little point in sticking a flywheel on it (unlike the DS10)."

I further note that a 1220 spins at a peak 11000rpm whereas a DS10 does 22000rpm.

Does this mean that my mashima 1220 (in Taliesin) would not be worth a flywheel?

Colin
Title: Re: flywheels
Post by: JulienW on September 02, 2008, 16:18
Quote from: rhydddu009 on August 27, 2008, 15:01
thanks.  In just reading 'loco kit chassis construction' by Iain Rice I note that he states about the mashima 1220 (or similar 1224) that...

"due to the low-revving nature of the motor, there's precious little point in sticking a flywheel on it (unlike the DS10)."

I further note that a 1220 spins at a peak 11000rpm whereas a DS10 does 22000rpm.

Does this mean that my K1 (which I think has 2 x DS10) would be worth it, but the mashima 1220 (in Taliesin) would not be, or is he wrong?

Colin

The idea of fitting a flywheel to a motor is mainly to increase the rotating mass and thereby increase the inertia.  This allows the motor to continue to spin when the current is off, say when the loco hits a bit if dirty track.

The flywheel effect is dependent on a number of factors, mainly the weight and diameter of the flywheel, but also how fast it is spinning.  There is a lot of physics involved (most of which I have forgotten, my B grade at A level was a while ago now!), but essentially the best shape is to have a thick rim and a thin middle (even a spoked middle).

What Iain may be getting at is that it has less of an effect at lower motor speeds.  But most 009 locos tend to use higher gear ratios compared to standard gauge ones, so whereas a mainline passenger loco with 6 foot wheels would use a gear ratio of, say, 30 or 40 to 1, the average Branchlines kit will be 60 (or more!) to 1 with a much smaller wheel diameter.  For the same line speed, the motor in the 009 loco will be spinning at something like four times the rpm (2 times gear ratios and 2 times wheel diameter) of the same motor in the mainline loco.

As to whether it is worth fitting one to your Mashima 1220...  I fitted a flywheel to my Backwoods Hudswell Clarke diesel (12 mm dia from memory, which JUST fits in the body, bought from Branchlines) which I think has the same motor and it improved the running.

Remember though that a flywheel will not make a poor running loco run well, just make a good one better.
Title: Re: flywheels
Post by: rhydddu009 on September 02, 2008, 17:01
Thanks Julien - good point about the gears and wheel size!  Flywheel here we come!  Now I've just got to find room for the motor, flywheel and decoder!  ouch.
Title: Re: flywheels
Post by: pilotfriend on September 05, 2008, 09:09
We fit all locos on County Gate with flywheels, although, of course, their size could be larger to get the best effect.
Title: Re: flywheels
Post by: pfwebb on October 31, 2008, 00:16
I have a flywheel on a Backwoods Taliesin which I fitted during the build.  The loco is a beautiful runner but I cann't be sure if it is the gearing or flywheel! 
Make sure the bogie is not too loose as the loco will rock as the motor starts (More physics!)
Title: Re: flywheels
Post by: rhydddu009 on October 31, 2008, 11:43
Hi - can I ask what size you fitted to Tal?  Thanks Colin 
Title: Re: flywheels
Post by: pilotfriend on January 31, 2009, 08:48
Where possible, I always fit flywheels to County Gate stock. On a dead clean test track, the difference is not always discernable but on a layout, it can mean the difference between the deployment of the 'hand of God' or not. Equally important is to pick up current from as many wheels as you can. I always use pony trucks too for the purpose.
JdF