Crank Axle and Driving wheels

[durhambuilder]

I'm about to fix the main driving wheels to the crank axle of my 4-4-0 Super Claud and wondered if there is a correct alignment. Do the balance weights on the wheels have to be set in relation to the cranks or does it not really matter in this scale?

Thanks

Julian

[digger]

I would just position the balance weights, as deduced from photographs of the class, if they are not shown on the general arrangement drawing.
Great accuracy not really a requirement, as I suspect in our gauges the weights will have little effect.
On my GWR Manor the spaces between the front and back balance weight plates were filled with Belzona Molecular metal, to add a little weight, though I dont't think that was strictly necessary.

Digger

[Deleted]

Dec 17, 2012 21:38:05 GMT durhambuilder said:

I'm about to fix the main driving wheels to the crank axle of my 4-4-0 Super Claud and wondered if there is a correct alignment. Do the balance weights on the wheels have to be set in relation to the cranks or does it not really matter in this scale?

Not sure I understand the question. Are your balance weights part of the wheel casting, or are you adding them seperately?

Normal practice is for the outside crankpins to be 180° from the inside crank, on the same side of the engine (if that makes sense). If your weights are cast in, their position is automatically fixed. If you're adding them, do as digger says and consult photos.

[jma1009]

the super clauds had very 'narrow' balance weights on the driving wheels in what might be described as the quarter to the rear of the wheel crankpin. if say the wheel crankpin is at 6 o'clock, the balance weight is from 6 o'clock to 3 or 4 o'clock.

the crankpin on the wheel would be 180 degrees opposite the crank on the crank axle next to that wheel. (this is the opposite of the Stroudley arrangement)

i think it is always a good idea to attempt some form of balancing on a miniature loco, as well as ensuring that the miniature follows it's fullsize prototype in respect of these details.

cheers,
julian

[durhambuilder]

Thanks guys, much appreciated. Yes the balance weights are cast in very roughly about 90 degrees from the crank pin bosses. I guess It would have been clearer to ask the relationship between the crank axle and the crank pin. I'll do them at 180 degrees as Julian and superseven suggested.

Many Thanks.

Julian

[steamjohn248]

Is the Claud you are building being done from available drawings if so where from. I went to School behind then them and would consider building one but in 7 1/4". Got any pictures to put up.

Many thanks

John

[durhambuilder]

John,

It's the Martin Evans Super Claud which is not strictly to scale, doom mongers say its all wrong to the original but I think it's a great looking miniature which at the end of the day is good enough for me. Station road steam had a lovely 7 1/4" claud in a few months ago, photos in their archive.


Happy Christmas all.

Julian

[steamjohn248]

Thanks Julian, I always remember them as good looking engines though by the time I saw them on a daily basis they were very scruffy and getting tired. I'll see what is available in the way of drawings.

Cheers

John