In the TV series, the models used were made to the scale of 1:32 or Gauge 1 using a series of Marklin parts and perspex sheets and tubing.
Recently I've seen fans of the show tackle at making replicas of these models using the same parts that were used, some going as far as to fitting a working eye mechanism and smoke. It's quite impressive.
But I've also seen fans and also a few modellers making their own Thomas by means of a simple conversion of a simple toy. The die cast company ERTL once made an RC Thomas which was a larger version of their pull back and go toy. Two versions of this toy were made, the second being used as a money box. But the boy it's self is a suitable size of gauge 1 and this is where some modellers use it for their advantage. Some years ago I came across modeller Ronald Pointer's model of Thomas which was made using an ERTL body as it's basis. He simply made an RC chassis for it to run on as well as adding a few extra items such as steps and a chimney cap and that was that. You can find photos of that model via the link here: http://www.wisbechstandard.co.uk/news/gallery-hundreds-celebrate-100th-birthday-of-thomas-the-tank-engine-author-1-919838
Having a g-scale garden railway of my own, I thought it would be fun to have a gauge 1 Thomas to run on it. So using Ronald's model as a reference, I set to work on gathering up the items to make it. The first thing to get was an ERTL Thomas. Luckily for me I managed to obtain one off eBay for £1 - what a bargain.

I next then had to see about what chassis I was going to fit it with. The best one i could find which also had the correct wheel spacing was the PIKO motor blocks which can be available to buy from g-bits.co.uk

Finally are the buffers and couplings. These have been ordered from Walsall Model Industries so once they arrive I can fit them on.
In the mean time I can see about getting the motor block to fit onto Thomas' body. The body comes away by two screws and the footplate the same. Now I had to cut a small amount away from the middle of the footplate to allow the top part of the motor block to fit in snuggly. This also gives me enough room as well to store the LGB MTS decoder as well.

Now lets see how Thomas looks with his body now back on.

So far so good. There are a few gaps that can be filled with some postcard which will also give the motor block extra support. I will also see about making up some steps as well to add a bit of extra detail to the model.
Finally I had these side rods made for me by a friend in the USA. They slot into these plugs which are made to fit into the holes in the wheels. Just need to get some E clips to secure them on and that should do it.

So for now this is how Thomas currently looks. As soon as the buffers and couplings arrive, I can make a start on fitting them on and start repainting the foot plate as well as repainting the motor block.
Part will cover all of that.