A Simplex visitor on the Dyfrdwy Tramway...

I've known Steve Milner for a few months now, and he's become a good modelling friend. Steve also models in 7/8ths, and like me uses 32mm gauge track. He is also relatively local so it's amazing that it's taken until now to get one of his lovely models down to run on the tramway...

You may remember a few of his other models that I've painted and weathered? (here and here) but this one is so far all his own doing and is completely amazing. It's a bow framed Simplex, completely scratch built. It uses a micro motor and delrin chain drive, and has a sound card which sounds completely superb, a 'Lister twin' which just sounds perfect for this smaller 20hp machine.

It was great to run it on the tramway, because we're in the process of a joint project building ourselves a pair of matching diesels that are using a similar drive concept. My existing Simplex 40S uses a PDF models drive unit, which is a great smooth runner from a crawl to a slow jog, but the problem is it uses a worm drive in the reduction gearing. This is fine going up the hill, but on the steeper descents this can mean the weight of the train pushing against the drive wants to speed the engine up, but the worm stops this happening (I wonder if the motor controller can't read an increase in back EMF and adjust accordingly) which then causes a loud squeal from the drive and a sudden stop as it momentarily jams before carrying on. This can be avoided with careful driving, to speed up slightly as you get to the steepest slope to carry the locomotive through this section, but it's frustrating.

As Steve's Simplex has a micro gearbox fitted, and no worm in the reduction, his engine performed faultlessly along the whole length of the line, looking and sounding very much at home. I can't wait for him to visit again with more of his lovely models. More soon...