So, on one of the occassions I visited John (Bogstandard) last year he showed me some plans he had of a Sterling Engine.

It was a Desk Fan powered by a small alcohol burner. There and then I determined I would build one for my good lady for Christmas. Slowly over the year I gathered together all of the various mmaterials I would need for the build.

Now, without going over the details, towards the end of last year I had a number of issues I had to deal with beyond my control. However – letting my good lady down was just not on the agenda – it was the 21st December when I started this project and thus began three days of very intense machining, I didn't get much sleep!

I had made a few decisions regarding materials and design, the main cylinder on the drawing was round but I left mine square, I liked the asthetic. The Hot Cap calls for Stainless Steel because of the heat transfer (or lack of them) qualities. What is even better than Stainless in this regard is Titanium, and as I had some in stock……..
I also used Titanium for the two flywheels and it worked well with a nice finish.

One of the components that I thought was quite chalolenging was the main "hot" piston. It called for a flat bottomed cylinder with thin walls and a very thin base – plenty of room for error. I was pleasantly surprised as to how straightforward this was. Just simple, steady machining paying full attention to what I was doing and it came out allright:

The main cylinder was interesting too, I left it square so plenty of scope to knock a corner off or bend a cooling vane here:

The component came out well and the piston was a superb fit, exactly as the drawing.

I had considered making the conrod out of Titanium too, but with time being a major consideration, I stuck to aluminium. I enjoyed making this part, very fine tolerances and small drills and cutters. Making this part caused me to buy a couple of pairs of those magnifying headsets, wish I had bought them sooner to be honest.

Next up was the Hot Cap, I just went for it:

It was tough to machine:

With (literally) hours to go it started to take shape and here you can see the power cylinder turned round in contrast to the main cylinder:

The fan hub was challenging as I recall but it was towards the end and I was suffering from a bit of burnout by then so the actual facts and what I recall may not have been the same thing

So, was it worth it?
Absolutely, no question, my good lady has it in the Living room – things need to be of a certain "standard" to achieve the honour, excludes me some days) All the Bloke type visitors are very interested in it, how it works and when I explain it is a flame powered desk fan you can see in some of their faces the light going on as they realise how Steam Punk this really is.
I am not a "model engineer" as such, but I AM interested in all things mechanical and the Stirling Engine has been of interest to me for some time, I sincerely believe it could play a major part in so-called "renewable energy". Would I build another? Quite possibly, it was intense but still very enjoyable and that could apply to anything however those of you who have built working models will know the sense of real achievement when it actually works! Very, very satisfying and there is no substitute for that feeling.

My thanks go to Ian for telling me "just do it" when we discussed building this and my eternal gratitude to John for supplying me with some of the components I needed for the build.

graham.