The Diary of the Building of a 5" gauge Stirling Single

    

Running in the basic chassis


Why Run On Air

I consider that running a model steam engine on compressed air is a great way to check out the locomotive engines I build to access if it runs and solve any problems before completing the construction with boiler etc etc. 
Running on compressed air I do not have to think about what might be hot and then if amendments are needed there is no cooling down time. Using compressed air leaves no evidence of running such as burnt paint, accumulation of soot.
The air line from a compressor must be used, in my opinion, with a pressure gauge and a regulator as I would guess that most locos have their regulator integrated inside the boiler.
10th November 2017

Ran the engine for about 30 minutes in 15 minute sessions and keeping all moving parts well oiled and putting oil in the air line inlet to the engine. Running both forward and in reverse worked well.
I used my laser rev counter and it indicated and off load max rotation of the driving wheel at 300 RPM. This equated to a track speed of about 9.5 MPH with the 8.75" wheels which actually would be over speed as the max track speed allowed is 8 MPH.With a scale of approx 1:12 that gives a full size speed of 114 MPH which is actually higher than the actual top speed of the full sized Stirling Single of 85 miles per hour. So I only need a speed of about 7 MPH to be a near scale speed.
11th November 2017

Demonstrated the engine running on compressed air to my friend Paul, and it ran well forwards and backwards even at low regulator level.

12th November 20917

Further running in for about 15 minutes, I must find the leak of air from the compressor !

I am to make up a mix of oil for lubrication for the moving parts until run on steam oil in the cylinder, as suggested by Keith Appleton
 of
50% light engine oil
25% light machine oil
25% Rape seed oil
23rd November 2017

Just a few minutes in the workshop considering what to do to assist the running in so provided and in-line oiler in the compressed air line. I wonder if it will work ?

24th November 2017

I made up a mixture of 50% Light machine oil and 50% Rape seed oil as still running on air so decided to leave out the Steam oil.
Ran on air for about 15 minutes.

25th November 2017

I had been concerned for a few days as to what was causing a knocking as the wheels went round. I found that the right hand side main bearing had split slightly apart. As soon as it was back together again the knocking stopped. I ran the loco in for about 30 minutes of low air pressure and the wheels turned round very well.