Hi Paul, I'm sorry that you've to wait so long but I had some difficulties with the photos.I made the power piston from a carbon rod which I took from an old electric engine. This LTD engine works with a temperature difference of 20 degrees. I hope to make some improvements so that it'll work with a lower temperature difference too. If you or a other model engineer is able to give me some advice, this it would be very nice. You wrote that you want a construction diary with photos. I attached to this mail some photos showing my engine. If you want a description of the building of the engine too please don't hesitate to express your wishes.
Naturally, I've mailed Dietmar back asking for the full story to include here, but in the mean time here are the photos which show the high standard of Dietmar's work.