Live steam model on 7¼" gauge of the Württembergische T3 no 924

Welcome to this blog. It will inform you about the progress of designing and building miniature live steam, coal fired locomotives for passenger hauling. Currently I'm working on a 7¼" gauge, scale 1:8, German T3 steam locomotive.

In 2006 I started this new project. This is a small 0-6-0 branch line locomotive of the German KWStE (Königlich Württembergischen Staatseisenbahnen) origin with outside cylinders and Walschaerts valve gear. The loco is about 1.10 metre long and will weigh approx. 100 kg.

On the left you'll find the index where you can browse through the different articles and on the right you'll find all the extra's. On the top tabs you'll find a brief description of my other locos.

Enjoy this site. Erik-Jan Stroetinga. The Netherlands. Europe.

Friday, 31 March 2017

Completing the running gear

The assembly of the running gear of the loco is now on it's way. Also some parts have to be made, for finishing the locomotive.

Wooden coffee stirrers are used to make a floor in the toolboxes below the cab. With a polyurethane glue, these sticks were glued on some cross members and left to dry. 

After cutting them to size and painting them with varnish they make a nice floor. On the real loco these were used to prevent the tools from rattling in the toolbox, and thus keeping the noise level down during the ride. 

I had some trouble with so called 'fish eyes' in the paint. (small spots appearing in the paint after spraying).  According the book "How (not) to paint a locomotive" it could be water in the air that caused it. Although I had a simple water separator, I bought an extra one and installed it with an extra air hose between the compressor and spray gun . The problem was cured.  

Setting the valves and sealing the cylinder block is not difficult. But it takes up a whole weekend to assemble all these parts.

With a Loctite sealant the steam chest cover is mounted. 

The cylinder covers are painted in RAL 7021; black grey.  This is the colour that will be used for the cab and tanks.  All components are in place for the first tests on compressed air. 

Although a bit stiff in the beginning, it soon started to move freely. 

  A short video of the locomotive running on compressed air. 

The running boards are painted red on the underside and black on the top. By spraying them in this position (outside of course), no masking is needed. 

The connection of steam inlet and exhaust; even on 7¼" gauge there isn't much space for wrenches or hands to assemble these parts.

The water pump is driven by an eccentric on the first axle. The gland nut is sealed with an o-ring. This o-ring is supported with a custom made nylon ring, so that there is just enough compression on the stainless steel pump ram to prevent leakage, without being too stiff and cause too much friction.

The pump assembly.  The back plate makes it possible that this pump can be removed for maintenance, (after disconnecting the feed and delivery pipes) from the loco with only four M3 screws.  

On the top of the right water tank the bypass valve is mounted. Where with British locomotives this is nicely tucked away between the tanks and boiler, the German engineers put this all on top of the tanks and boiler. Maybe not the esthetical for the appearance of the loco, but  it is very easy for maintenance!
The return pipe is seen in the picture, where it enters the tank.

The first fitting of the delivery pipes of the axle pump. 

The running boards, smokebox, mechanical lubricator and oil tank for the axle pump eccentric fitted.