My first Hot Air (Stirling) Engine
- Thread starter NickG
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Yeah, mine has a leak on the power cylinder, I could hear it if put my ear right next to it when running. Didn't lap the piston or the cylinder, the piston had an amazing finish straight from the lathe so just left it! The cylinder wasn't too clever though, I tried to ream it with little success, so really it wants a new cylinder making and lapping to suit the piston, that'll probably be easier than making a new piston.
It'll probably also leak around the displacer rod as I damaged it when gripping in vice to tighten (silly boy ... well I was in a rush to see if it worked!) so when I got rid of the burrs it's now probably a bit smaller than it should be. Also think because of that the displacer is catching the wall of the hot cap slightly, there is slight scraping noise now that I couldn't hear before.
All of these things definitely aren't helping my cause but I don't want to spend time making new components really, I could be on for ever and would probably re-do the whole thing if I started that!
I want get it running acceptably for a short demonstration with cold water in the jacket and the meths burner, then move onto the next project!
Just bought a new XJ20 milling machine from a guy on ebay, looks a pretty decent sturdy machine for the money so that should improve my capability too.
Nick
It'll probably also leak around the displacer rod as I damaged it when gripping in vice to tighten (silly boy ... well I was in a rush to see if it worked!) so when I got rid of the burrs it's now probably a bit smaller than it should be. Also think because of that the displacer is catching the wall of the hot cap slightly, there is slight scraping noise now that I couldn't hear before.
All of these things definitely aren't helping my cause but I don't want to spend time making new components really, I could be on for ever and would probably re-do the whole thing if I started that!
I want get it running acceptably for a short demonstration with cold water in the jacket and the meths burner, then move onto the next project!
Just bought a new XJ20 milling machine from a guy on ebay, looks a pretty decent sturdy machine for the money so that should improve my capability too.
Nick
Hi all, I decided continue with the water jacket I started so that I could do short demonstrations of the engine running. I just finished the water jacket last night however, the engine would not run with water in the jacket. I don't think it will run with just water cooling without major rework. Unless I have just reassembled in a different position which has more friction. I did make a new displacer rod with a better fit and slot the hole the displacer pillar sits in to allow me to better align things and get rid of the skew when you look from the top.
If not, I think it would probably need some way of insulating between the hot and cold end, possibly a flanged hot cap with insulating material between rather than a screw thread. Also, it would be better with a larger swept volume of displacement piston.
I think I will just leave this one now and learn from the experiences and mistakes I have made!
The next project is to get an old 3 1/2" Gauge Locomotive which I did not build boiler tested and up and running. Then I will do a flame licker based on one of Jan Ridders, an i.c. engine again, based on Jan Ridders pressure controlled two stroke then my main, big project, a 5" gauge sweet pea locomotive. I have to do this as I bought the boiler and castings about 11 years ago!
Here are a few pics of the finished engine anyway.
If not, I think it would probably need some way of insulating between the hot and cold end, possibly a flanged hot cap with insulating material between rather than a screw thread. Also, it would be better with a larger swept volume of displacement piston.
I think I will just leave this one now and learn from the experiences and mistakes I have made!
The next project is to get an old 3 1/2" Gauge Locomotive which I did not build boiler tested and up and running. Then I will do a flame licker based on one of Jan Ridders, an i.c. engine again, based on Jan Ridders pressure controlled two stroke then my main, big project, a 5" gauge sweet pea locomotive. I have to do this as I bought the boiler and castings about 11 years ago!
Here are a few pics of the finished engine anyway.
