Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Hi Chaps.

 As many of you know, I have built my own version of the OPITEC, hot air engine kit.....




 Used, ball race main and big end bearings. Solid alloy displacer......







I decided, balancing slots. Instead of holes. In the flywheels.

The piston side was balanced nicely.....




The solid aluminium displacer was too heavy. The engine whizzed around the table top. Like a mad thing.

I inserted a 10mm brass "bead", with a 1mm hole through. This made it jump up n down!

Gradually opening the hole, lightened the bead. Balancing the vibrations to negligible.......




Runs nicely, and smoothly.......




All ready for it's first show, on Easter Monday.

Definitely smooooooooth as glass now ... nice work you've done to get it to this point!

excellent work and a great runner. I have only built one hot air engine (1/2 scale essex). It was from a casting kit and still challenged my skill level to finally get it running. I am super impressed!
crazydoug

Very nice job on that David and its running so very smoothly.

top quality build as always 

Great job on that, very well done David !

Thanks for all your kind replies, Chaps!

Most of my show days, are seen by the "ordinary" public, at Papplewick Pumping Station.
 Most of them understand steam engines. But, often, they have never come across stirling cycle engines.

Many are very surprised, how rapidly the expand/ contract cycle  operates.
 This engine, with it's visible displacer, and 1200rpm should answer a few questions.......