Richard Gawler
Western Thunderer
Simon thank you for all of your comments. For the time being . . .
![DSC_0027.jpg DSC_0027.jpg](https://www.westernthunder.co.uk/data/attachments/167/167527-a663c4952b3fee944bc7ba1db6a968b3.jpg)
The rear axle can drop like this. It can also rise more than 0.75 mm above the drivers (measured with a strip of styrene) but this is harder to photograph.
When I arranged this, one of my thoughts was that this rear axle shouldn't interfere with a rocking axle at the front.
I don't know how many wheels are on the track at the same time. I want to think always four, usually five. These being three of the drivers and one or both of the trailing wheels. Suppose I arrange some pickups on the trailing wheels and connect the motor to only these, I would find out how much wheel/rail contact there really is at the rear axle. I imagine, if only one driver of a pair is touching its rail then the loco will have a desire to yaw, but maybe this is for only a fraction of a second.
To be honest, the haulage capacity of Nellie is more than adequate for me. If she goes out onto the main line with a tender truck, an open wagon and a brake van this would be fine for me. Still, the more I learn from this the more I will know before I begin my next loco.
I should emphasise - I don't have any aversions to compensation, but this is my first 7 mm loco kit and I have been cautious with the driving wheels.
Edit: and after looking at this photograph I need to go and find at least one crank pin bush![Oops! :oops: :oops:](/styles/default/xenforo/smilies/redface.png)
I suspect you have, at least at times, only three wheels in contact with the track, and maybe only one of them is a driver.
The rocking axle will improve matters but only usefully if the trailing axle isn’t holding the middle axle off the rails.
![DSC_0027.jpg DSC_0027.jpg](https://www.westernthunder.co.uk/data/attachments/167/167527-a663c4952b3fee944bc7ba1db6a968b3.jpg)
The rear axle can drop like this. It can also rise more than 0.75 mm above the drivers (measured with a strip of styrene) but this is harder to photograph.
When I arranged this, one of my thoughts was that this rear axle shouldn't interfere with a rocking axle at the front.
I don't know how many wheels are on the track at the same time. I want to think always four, usually five. These being three of the drivers and one or both of the trailing wheels. Suppose I arrange some pickups on the trailing wheels and connect the motor to only these, I would find out how much wheel/rail contact there really is at the rear axle. I imagine, if only one driver of a pair is touching its rail then the loco will have a desire to yaw, but maybe this is for only a fraction of a second.
To be honest, the haulage capacity of Nellie is more than adequate for me. If she goes out onto the main line with a tender truck, an open wagon and a brake van this would be fine for me. Still, the more I learn from this the more I will know before I begin my next loco.
I should emphasise - I don't have any aversions to compensation, but this is my first 7 mm loco kit and I have been cautious with the driving wheels.
Edit: and after looking at this photograph I need to go and find at least one crank pin bush
![Oops! :oops: :oops:](/styles/default/xenforo/smilies/redface.png)