Green G30 Sleeve Valve Engine

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Fluffy

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Nov 1, 2012
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Location
Lismore, NSW. Australia.
G'Day All,
I am currently attempting to build a Green G30 sleeve valve aero engine. This engine build came about thanks to an aquantence giving me a box of various engine castings/kits, that he has collected over the past 30 years. In his words, he has come to the realisation that he will never get around to building any of them, so I have become the beneficiary.
I had not seen a sleeve valve engine of any design prior to this & this one has aroused my interest. I had to convert the imperial detail drawings to metric & here goes.

Has any forum member built this engine?

DSCF4310.jpg
This is a purpose made angle plate to allow the crankcase casting to be held in a 4 jaw chuck. Just a piece of 75x75x10 angle. I have found that black etching primer makes a great marking medium.

DSCF4318.jpg
Image showing the cylinder liner bore at finished size. The visible thread is M30x1.

DSCF4323.jpg
Image showing first steps at grooving the cooling fins. The fin barrel was offset 3.2mm then the middle fins grooved. This gives enough material to allow the inlet & exhaust ports to be produced.

DSCF4395.jpg
Finished fin barrel.

DSCF4392.jpg
Almost completed crankcase (3 x M3 holes to do) & the front bearing extension (M30x1 thread) & timing case cover (M28x1 thread).

DSCF4393.jpg
Assembled crankcase.

Regards,
Don.
 
Very unusual/ interestting.
Can you show us a general arrangement and what is the history of this design?
 
G'Day All,
Thanks Brian.
Niels, I do not have a general arrangement drawing drawn at this time & I do not know the development history of the engine. The concept simply intrigued me.

The following images are of the cylinder liner & the sleeve valve.

DSCF4404.jpg

The cylinder liner (left) was turned from 4E cast iron with the outside diameter being a size for size fit into the fin barrel. The liner bore was honed to final size using a barrel lap.
The sleeve valve was turned from 4140 steel. The outside diameter honed to give a slight resistance sliding fit into the cylinder liner. A bearing housing was sliver soldered in position, with its ID finished with a ball nose end mill. This was done prior to the bore being turned to final size. The bore was then honed to final size, again with a barrel lap.
The ports in both were drill & filed to the final sizes. The relief areas endmilled to size & shape.
Regards,
Don.
 
G'Day All,
The crankshaft has been finish & fortunately I had no problems. The crankpin was turned by offsetting the blank in a four jaw & finished to size. The material used is 4140 steel.

DSCF4372.jpg

The profile of the web sides was then milled while maximum metal conditions still existed.

DSCF4376.jpg

The rest of the crankshaft was just a parallel turning exercise between centres.

A Ø20mm sleeve was made to hold the crankshaft to allow the material behind the crankpin to be relieved.

DSCF4383.jpg

Set up used to relieve the crank web.

DSCF4386.jpg

The finished crankshaft.
DSCF4405.jpg
DSCF4408.jpg

Has anyone any method that they use to stop the cutting oil staining the bare steel surfaces of chucks etc. The brown markings on the four jaw (first image) is not rust, but a brown stain left by Rocol RTD. The stain occurs within a couple of hours if left on the surface.
Regards,
Don.
 
Thanks Herbiev. I will try to obtain some of the Cleancut oil via Blackwoods.

Thanks for your kind words RichD. I hope to have the conrod & piston finished this week.
Regards,
Don.
 
Very interesting engine and nice workmanship Don.
Following.
 
Thanks Simon. Sorry about the delay in reply but I have been away.
Lohring, thanks for the link. I have translated most of the text & it makes interesting reading. The engine is a little more complex in its design that this engine. I also have reservations about the crankcase & valve lubrication. I guess I will see what happens in due course.
Regards,
Don.
 
G'Day All,
After far too many interruptions over the last few months I have finally got back to this engine.
As the kit fortunately came with the timing gears, the only work to do on the gears was to turn the larger timing gear to accept a ball bearing & to turn a counter mass on one side. I made a little jig to hold the gear as it was not possible to hold the gear itself & be offset to enable the offset required to be achieved.
DSCF4427.jpg

Large timing gear with completed counter mass.
DSCF4428.jpg

All the completed parts of the engine with the exception of the piston ring & the same size ring for the cylinder head.
DSCF4444.jpg

The cast iron rings are Ø20 x 0.8 x 0.8mm section & will be finished this week. The only problem with the rings of this small section that I am concerned about is getting them into the ring grooves in one piece even with the aid of a ring expander (I have made 6, hopefully 2 will survive). The rings here are roughed out over size & will be held on mandrels to bring them to the finished sizes after they have split & gapped.

DSCF4413.jpg

Regards,
Don.
 
Since the groove is so close to the top edge you might be able to do it by inserting one end in the groove and then spiral the other end into the ring groove.
 
G'Day All,
I am currently attempting to build a Green G30 sleeve valve aero engine. This engine build came about thanks to an aquantence giving me a box of various engine castings/kits, that he has collected over the past 30 years. In his words, he has come to the realisation that he will never get around to building any of them, so I have become the beneficiary.
I had not seen a sleeve valve engine of any design prior to this & this one has aroused my interest. I had to convert the imperial detail drawings to metric & here goes.

Has any forum member built this engine?

View attachment 74840
This is a purpose made angle plate to allow the crankcase casting to be held in a 4 jaw chuck. Just a piece of 75x75x10 angle. I have found that black etching primer makes a great marking medium.

View attachment 74841
Image showing the cylinder liner bore at finished size. The visible thread is M30x1.

View attachment 74842
Image showing first steps at grooving the cooling fins. The fin barrel was offset 3.2mm then the middle fins grooved. This gives enough material to allow the inlet & exhaust ports to be produced.

View attachment 74843
Finished fin barrel.

View attachment 74844
Almost completed crankcase (3 x M3 holes to do) & the front bearing extension (M30x1 thread) & timing case cover (M28x1 thread).

View attachment 74845
Assembled crankcase.

Regards,
Don.
Hi
Where can I locate a set of drawings for this engine?
Clive
 
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