Welcome

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 German (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.

Thursday, 11 July 2013

The mechanical lubricator.

Lubricator with twin pumps.  (These will feed the cylinders with steam oil).



This pump is driven by roller clutches. The ratchet wheel is omitted this way, which makes it a reliable system
The clutches were obtained from http://www.pollymodelengineering.co.uk/, the outside dimension is a bit odd (6.52mm) and a special hole had to be turned for press fitting the clutch in the tank. The tank is made off 1,5mm brass and is silver soldered. 
The scotch cranks are driven by a stainless steel eccentrics whit a throw of 4 mm. Here the two cranks are milled from a piece of scrap bronze.



The pump rams are made of 3mm stainless steel and are moving in a brass pump house. A close tolerance between pump ram and pump house is needed. (0.02mm)



The hand wheel and lever were CNC-milled on the new Wabeco machine.
There are two non-return valves  (check-valves), one right under the pump ram and one only 30mm away in the brass housing on the left. I've chosen for two individual pumps, one for each cylinder.


The brass lid was formed over a steel former plate. The tiny hinges were filed by hand.



The almost finished lubricator. It will be placed on the running board, under the water tank. The middle side door will give access to lubricator. 


This is the Solidworks design I've made for this pump. 
I still have to decide if a small sight glass will be necessary. Maybe by just checking the oil level by opening the lid will be ok.

This will be the drive system for the lubricator. Taken from the valve gear and reduced in swing by an intermediate tumbler. The complete lubricator can be removed by releasing two screws, uncouple the oil pipes and drive link and taking it out via the under side. This should make maintenance easier.


The Solidworks view of the loco.



After installing the pump, we found that the oil level in the tank was hard to see. A small sight glass would be useful. The window frame was milled from solid brass and cut of with a large saw cutter


The frame for a 6 mm wide, 24 mm long and 2 mm thick glass. The glass was cut from a piece of glass of an old picture frame.


Making the opening in the tank, and tapping M2.




The opening in the running board. The lubricator can be inserted from the bottom. This makes removal for maintenance purposes easier.



A drain plug on the underside was also added.


A small piece of white coated aluminium (salvaged from an old CD player housing)
was positioned a few millimetres behind the glass. This makes reading the oil level easier under bad lighting conditions. 


The lubricator on the loco, sitting behind the inspection door.


An extra oil check valve has been made, to make sure that the lubricator will give longer trouble free operation and needs les frequently maintenance. Click here to read about this valve.