2-cylinder Gamma - project

[Ian S C]

I find something similar with my motors in the cold weather, the ones that run on LPG I put down to the reduced gas out put in the cold weather. Some times the gas cylinder is so cold that there is not enough pressure to get a flame. Ian S C

[Triangle.Stirling]

hi,

about LPG, i can understand that, but my burners burn a butane/propane mix, and last winter it wasn't what you would call very cold, most times it was about 5 degrees C.

I think heat escaping to the surrounding area is the biggest problem.

[Ian S C]

At one time the retailer sold a different mix in winter time, but I don't think they do now here. And the Meths we get doesn't seem as hot as it was. Ian S C

[Triangle.Stirling]

Hi there!

An update from about this engine!

I Disassembled the engine, and i'm now completely rebuilding it. There are quite a few parts that will be remade, beginning with the crankshaft en top-plate.
The new parts will be amazing, I got acces to a fully equipped metal workshop, and got some help for the machines.
So now i can use a lathe and a computer controlled mill!
For my new crankshaft, this is ideal. I can drill the holes with te mill, much more precise than it is now.

I hope to post a few updates soon, it's my vacation now, so i hope to start working on the crankshaft very soon.

Regards,

Krijn, from the Netherlands

Oh, and check out my video about disassembling the engine!
[youtube]http://www.youtube.com/watch?v=VqXd-bRGcWY[/youtube]

[ilovesteel99]

how do you work out the displacement? thanks and also is your cylinder 3 times longer than the width? (216mm)

[Triangle.Stirling]

For the displacement i just tested how big a displacement i could make with the diaphragm.
The displacement of the displacer must be around 1.5 times as big. So i multiplied the displacement of the diaphragm with 1.5 and that's the displacement of the displacer cylinder.
With that information i could work out the stroke. I think I kept the ratio around 1.9 otherwise the stroke would be really short.

My cylinders aren't 3 times as long as the width. The width is 73 mm on the outside, the length is about 180 mm.
I couldn't make them 3 times as long, because my bottle isn't long enough.

I ran the engine with only a weth cloth as cooling, and when the bottom was red hot, i could run it for about 15 minutes, before the top of the cylinder exceeded 100 degrees Celsius.
So the shorter cylinder isn't really a problem i think, heat transfer is minimal.

Regards,

Krijn

P.S. Currently re-designing the whole engine, starting a video series about it soon, so stay tuned if you are interested !

[Ian S C]

Krijn, good on you getting it going. Got a friend who used a pair of his wife's knickers, just kept them soaked in water, worked well(don't know what his wife thought, but she did leave him some time later).
It will be good to see how you go with the new motor.
Ian S C

[Triangle.Stirling]

Here is the first video, just an introduction to the rebuild, and hoping that people get interested and follow the rest of the video's.
Enjoy!

Video!

[Triangle.Stirling]

Second part! : Part 2

Just a quick insight into a few changes I made.
It are all little changes, but I want this engine to be a lot better than the previous.
Next part will show the start of the Solidworks drawing!

[Triangle.Stirling]

And there it is, the start of the Solidworks drawing from wich the engine is going to be built.

Want to finish the rest of the drawing and start building, but school is busy. Hope to finish it sometime soon. Enjoy!

https://youtu.be/9EtGRlusjY8