Another finished Bonza.

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Fluffy

Well-Known Member
Joined
Nov 1, 2012
Messages
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Location
Lismore, NSW. Australia.
G'Day All,
After more interruptions than I can count, I have finally finished the Aussie Bonza.
The most satisfying part of the whole project was making the cast iron piston rings that are 1.25 x 1.35 mm section & Ø30 mm. Lots of swarf from Ø50 mm bar stock but it was what I had in the materials rack. I used the information by Tom Schwartz in issue No. 27 of the Model Engine Builder magazine for the ring sizing & ring/cylinder pressure & they have worked very well.
It was most gratifying when the engine started on the third pull of the starter chord. I have not made a video as yet only stills.
Regards,
Don.

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Hi Fluff
That is just lovely Mate!
The Golden flease on the Tank is a real nice touch :cool:
Pete
 
Bloody brilliant Don!

And it starts with a couple of pulls? Can't ask for more than that.

Congratulations mate

Jim
 
Don,
Absolutely stunning.
Finished off to perfection.
Photographed like a pro with a great backdrop to complement the engine.

Thanks for sharing. :bow::bow::bow:

Looking forward to seeing a video and hearing it run,

Baz
 
Very nice work Don. Thanks for sharing your work with us.

I wanted to study the plans for this engine for some time. At one time I thought they were available on this forum but a search was unsuccessful. Do you know if they are available elsewhere?

Cheers,
Phil
 
G'Day All,
Thank you all for your words of praise, it is greatly appreciated.
The Bonza was a nice engine to build & a fair bit of work to machine the flywheels from solid bar stock.

Phil: The plans for the Bonza were printed in the Australian Model Engineering magazine in issues 146 to 151 inclusive.

I did vary a little from the original drawings, being; I inserted cast iron valve seats & valve guides rather that just using the aluminium of the head & the water jacket is not brazed onto the cylinder but sealed with o-rings on the flanges of the cylinder body.

Thanks & regards,
Don.
 
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