Jonkman Stirling 60 Variant

[creast]

I was impressed with Jeroen Jonkman's Stirling '60' and decided to have a go.
This is my second Stirling and I wasn't keen on the two tier arrangement (everyone has their own preference), so I decided to keep it at one level and do it all in brass.
I have transferred the idea into SolidWorks to make things easier.
With hindsight I should have amended a few details to make construction easier.

At first I wasn't keen on the idea of brass on brass for the piston/cylinder combination but hey it does work.
I think the finning should be greater as there is a fair amount of heat getting up there.

The base was the biggest dilemma.
I chose to do a sort of tiered base which if fabricated would have cost around £30 here in the UK. Machining from solid was out of the question as I don#t have CNC (In progress!)
So, I decided to have a go at casting the main form and then cleaning it up with various lathe mill techniques.

I had cast aluminium before but not brass so this was a new experience for me.
First attempt lead to a short pour and too low a temperature.
Second resulted in the casting I used. I know it has defects but hey.. I would never finish the project if I was to attain perfection.

[ame]http://www.youtube.com/watch?v=3xMl4lokQpg&feature=c4-overview&list=UUnHIQQMyv3UwEX2dY4B__EA[/ame]

Overall I am very pleased with this engine and my gratitude goes to Jeroen for providing the plans.

[ame]http://www.youtube.com/watch?v=TjkI6os0mU8&feature=c4-overview&list=UUnHIQQMyv3UwEX2dY4B__EA[/ame]

 

[AussieJimG]

I'm impressed. That's a nice looking engine and I must admire your casting ability.

Jim

 

[creast]

Thanks for the kind words Jim.. its taken longer to finish than expected!

 

[jwcnc1911]

WOW! Very nice!

Is the displacer solid brass?

 

[creast]

No, it is bored out very thin to about 0.5mm wall but the end is drilled as close as I dared to keep the weight down.
Did try spinning a form but after 5 goes I gave up and turned the darn thing!!

 

[jwcnc1911]

well, you did great turning it! That thin and it didn't deform at all - that's why I asked if it was solid.

Good job on that engine!

because this is on my bucket list, where did you get the glass cylinder?

 

[Cogsy]

Beautiful engine and runs well too. Very impressive cast as well - something I aspire to achieve one day.

 

[creast]

well, you did great turning it! That thin and it didn't deform at all - that's why I asked if it was solid.

Good job on that engine!

because this is on my bucket list, where did you get the glass cylinder?

I used a 16mm od test tube and cut it to length with a diamond wheel.

 

[Ogaryd]

Beautiful job on that Stirling 60. Did you get your Kerzel straighten out?

 

[creast]

Beautiful job on that Stirling 60. Did you get your Kerzel straighten out?

Thank you.
The Kerzel got pushed to one side for a while. It does run nicely now but I still have had problems with the ignition circuit. Its probably because I am trying to hide it all in the base of the model and its a bit tight.
I will be getting back to it soon and hope to post on here.