Microcosm J065 Worlds Smallest HoneyBee Stirling Engine

[Jim]

Microcosm J065 Worlds Smallest HoneyBee Stirling Engine


Has anyone ever made a small engine? Do you have a link to the build thread or photos of it?

<a href="https://www.youtube.com/watch?v=TmvHabivbTg" target="_blank">http://www.youtube.com/watch?v=TmvHabivbTg</a>

[Jasonb]

Try this for size

<a href="https://www.youtube.com/watch?v=YCjwlSX-tsY" target="_blank">http://www.youtube.com/watch?v=YCjwlSX-tsY</a>

[Jim]

 Jason that is incredible and a credit to the skills of the maker.

I have a little run out (tiny but its there) on my Sieg C6 lathe. How accurate does a lathe have to be to make a Stirling engine?
My lathe is mounted on an old kitchen bench in my shed, I need to put it on a more substantial base (we flooded two years ago) and get the twist out of the bed.

[Jasonb]

You could probably say the same about my Warco 280 but my stirling engines work OK. It does become more of an issue as the parts become smaller if you think of the runout in relation to the diameter then fairly easy to see that 10microns on my 40mm cylinder is not going to be that noticable but it is 10times greater on a 4mm piston and 40times greater if that piston is on a 1mm dia rod.

Runout can be compensated for by doing as much in one setting as possible, using collets or custom turned split bushes which should be better than the average collet’s runout. It is clearances and alignment of parts as much as concentricity, lapping the power piston is going to be the critical fit if you are making alpha or gamma types. it gets a bit more complicated on the beta types where the power piston and displacer are on the same axis so displacer rod needs to pass through the power piston but they have been Ok for the ones I have done.

I’ve not really looked to see what small barstock designs might be out there as I prefer a scale look but there should be something and it can always be scaled down.

[90LX_Notch]

This is the smallest engine that I’ve done.


Bore:  .046  (1.16)
Stroke:  .046  (1.16)
Column height: .312  (7.94)
Ports: .013  (.33)
Center Distance of ports .023  (.58)
Crank Pin .016  (.41)
Fly Wheel Dia. .156  (3.96)


<a href="https://www.youtube.com/watch?v=nJau0iNTYOg" target="_blank">http://www.youtube.com/watch?v=nJau0iNTYOg</a>

[Vixen]

This is the smallest engine that I’ve done.

Top notch.... tinyest Tiny ever?

Mike

[MJM460]

Amazing work Bob. 

Now it just needs a miniature boiler and boat to suit!

MJM460

[crueby]

Wow! That's  incredible! 

[Jim]

You could probably say the same about my Warco 280 but my stirling engines work OK. It does become more of an issue as the parts become smaller if you think of the runout in relation to the diameter then fairly easy to see that 10microns on my 40mm cylinder is not going to be that noticable but it is 10times greater on a 4mm piston and 40times greater if that piston is on a 1mm dia rod.

Runout can be compensated for by doing as much in one setting as possible, using collets or custom turned split bushes which should be better than the average collet’s runout. It is clearances and alignment of parts as much as concentricity, lapping the power piston is going to be the critical fit if you are making alpha or gamma types. it gets a bit more complicated on the beta types where the power piston and displacer are on the same axis so displacer rod needs to pass through the power piston but they have been Ok for the ones I have done.

I’ve not really looked to see what small barstock designs might be out there as I prefer a scale look but there should be something and it can always be scaled down.

Thanks for that post Jason, I’ve gotten hold recently of some books on building Stirling engines as my enthusiasm to build something from scratch has built up (instead of just modifying, repairing and ‘building on’ already built engines.

Again, appreciate your post.

[Jim]

This is the smallest engine that I’ve done.


Bore:  .046  (1.16)
Stroke:  .046  (1.16)
Column height: .312  (7.94)
Ports: .013  (.33)
Center Distance of ports .023  (.58)
Crank Pin .016  (.41)
Fly Wheel Dia. .156  (3.96)


<a href="https://www.youtube.com/watch?v=nJau0iNTYOg" target="_blank">http://www.youtube.com/watch?v=nJau0iNTYOg</a>

Just amazing that build!
I had to share -

https://www.officeofsteamforum.com/general-discussion/'ultra-tiny'-steam-engine/msg65332/#msg65332

[90LX_Notch]

Thank you gentlemen for the nice comments.

Mike, it probably is the tinyest Tiny ever.

Jim, thanks for posting it on another site.

-Bob

[crueby]

So, next project is an ultra-tiny double-acting engine?


The pic that really made the teensy size hit home for me was the engine lost next to the M&M. Simply stunning.

    

[Jim]

Thank you gentlemen for the nice comments.

Mike, it probably is the tinyest Tiny ever.

Jim, thanks for posting it on another site.

-Bob

G'day Bob,

Looking through your channel, this engine looks like a good candidate for my 13 yo Grandson and myself to build together -

<a href="https://www.youtube.com/watch?v=wSRwQtJ5OpI" target="_blank">http://www.youtube.com/watch?v=wSRwQtJ5OpI</a>

[90LX_Notch]

Jim-

That engine was designed by NickG.  The plans were free on the HMEM site 15 years ago.  I left that site when it was sold.  I don’t know if the plans are still available.

-Bob

[Jim]

Jim-

That engine was designed by NickG.  The plans were free on the HMEM site 15 years ago.  I left that site when it was sold.  I don’t know if the plans are still available.

-Bob

Thanks Bob appreciated mate.