Author Topic: Axle Hung Motor Gearbox (AHMG)  (Read 20223 times)

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Offline IanT

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #195 on: February 24, 2016, 10:52:26 AM »
Doddy,

Mike's summary of where we are right now seems to be a reasonable one.

As for information not being available on the Forum itself, well there is obviously a practical limit to what can be posted here. I was asked for the CAD files for my design and I supplied a DXF and I think (?) a list of suppliers for the parts used. If anyone wants this data it's still available but as Phil discovered, it needed work to be usable. I will come back to this project when time and mood permits and anything I develop will be freely available to anyone who would like to make use of it.

I can't speak for the other guys but I've seen nothing to suggest that they would not be willing to take an equally open view.

So "Seek & Ye Shall Find" - or (in modern parlance) "Just Ask and You Will be Given"

Regards,

IanT
Nothing's ever Easy - At least the first time around.

Offline Peaky 556

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #196 on: February 24, 2016, 11:08:56 AM »
I have been asked (by the motor supplier) whether anyone on here would be interested in developing a double-motored gearbox.

I will quote what has been asked:-
...... I will discuss the mating of two motors facing each other, one running CW and the other CCW through the worm. ....... do you know of any member who would undertake this task ?

I am not going to comment or pass judgement on the advantages or disadvantages of such an arrangement but it would give double the "grunt" for the price of a single gearbox.

John.

John, do you not think this worm drive topic is outside the scope of "Axle Hung Motor Gearbox" as originally conceived by Ian T? I cannot imagine how such an arrangement would fit within a bogie.  Might I suggest a separate thread? Your decision of course,
Regards, Tim

Offline John Candy

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #197 on: February 24, 2016, 11:17:18 AM »
Ian,

It sounds as though this could be a topic for an item on g3madesimple.org.uk ?
It can list all the options, drawings in any format and details of component manufacturers.

Tim,

If anything comes of the double-motor unit, I will split to a new topic.

John
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline IanT

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #198 on: February 24, 2016, 02:53:10 PM »
I've no objection in principle John but as you will know, I already have a few other commitments at the moment.

My apologies to Doddy - as he had PM'd me yesterday morning to request information but I'm afraid I didn't notice I'd actually received a message until I was just about to log-off this morning.

However, I will help him as best I can.

Regards,

IanT
Nothing's ever Easy - At least the first time around.

Offline Peaky 556

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #199 on: February 24, 2016, 11:29:37 PM »
Tim,
Your definition of torque -I term as SHAFT torque. Thus the shaft torque from the gearbox motor combination is 2,778gcm. The RAIL HEAD torque is the torque available at the rail to wheel interface which should be 240gcm per kilogramme of down force at the interface.

Thus there is ample shaft torque to spin the wheels on an axle -or drive more than one set of axles.

It is almost the reverse of your method. I have 5 power axles, the model weighs in at 10 kg. Thus the maximum torque to the rail head I can put through each axle is 480gcm. The gearbox motor needs to develop a shaft torque of 2,400gcm. Given the figures above at 2,788gcm the "el cheapo" gearbox with its 60p bin hair drier motor -will do the job....
regard
ralph

Ahhh!  I see you are using this weird term "railhead torque" to use as a limiting figure for working back through the gear train to determine how many axles need to be powered.  Ok, but don't forget the rotational speed is a factor too.  Too much of a gear ratio drop and you end up with a high-torque, slow-speed shunter!

Are you using the term "60p bin hair drier motor" in a somewhat derogatory sense, as one might describe a car as a "hairdressers car"?  If so then my Peak will be extremely camp!!

???? Tim

Offline cabbage

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #200 on: February 25, 2016, 07:03:56 AM »
The term Rail Head Torque is one from the African Railways. This was used to specify how many power axles the locos would need to pull the wagons. This told the "agents" at the marshalling yard what sort of locos to couple up. Garret, Mallet, or Modified Fairlie. Thus 12 axles could be 4-6-4+4-6-4 with a 4-4-2+2-4-4 or if it was Wanke or Gwello shed -GOD ALONE knows what they would put on it...

As to high rotational speeds -the coal trains from Toten to Brent moved at 20mph -ours were nowhere near that rapid!!!

regards

ralph

Offline cabbage

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #201 on: February 25, 2016, 08:13:34 AM »
Having consulted P. Ransome-Wallis... The term in (BR) parlance is "Rail Tractive Effort".

As to disparaging the 60p motor -please remember that Ixion, No5, and Rosebud are all powered by 80p coffee machine motors. Which, given my required daily caffeine intake -is quite understandable.

regards

ralph

Offline John Candy

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #202 on: February 25, 2016, 08:37:35 AM »
Quote
the coal trains from Toten to Brent moved at 20mph -ours were nowhere near that rapid!!!

I hope some of the attendees at the garden GTGs are taking note.

"MGR" (Merry-go-Round) coal trains take on a new meaning at these events ....... MGR 125 would be appropriate description..... and hauled by a Horwich "Crab" or similar!!!!

Regards,
John
 ;D
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline Peaky 556

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #203 on: March 29, 2016, 11:31:04 PM »
Gents

The first 2 gearboxes have now been made to the final design that has evolved from Ian's initial drawings.  I have photographed one for members' information and the second is being incorporated into a trial Bo-Bo type bogie.  Both will be available to view at the AGM next weekend.

Phil

We're still holding our breath in anticipation of some test results Phil!  The gearboxes looked very nice, but I have a feeling these motors will turn out a little gutless, needing a lot of them to move a decent sized train fast.
I hope to be proved wrong!
 ???

Offline classicdelights

Re: Axle Hung Motor Gearbox (AHMG)
« Reply #204 on: March 30, 2016, 05:02:34 PM »
Nothing to run the bogie on unfortunately - no layout so no track!  I need to make the other bogie and then I will try and rig something up.

Regards

Phil