24cc DIESEL ENGINE FROM SOLID

[dean clarke 2Participant @deanclarke2]

Here’s the start point for this project, a lump of 6061 T6 ally, 4″square by 5″ long.

Next step is to machine the rear face to establish a fixed point datum and machine the inside of the case from the rear to give me a finished case internal and the ability to hold the case for the next machining operations. This also makes sure that everything done from here on in is true and square to the crankshaft centerline.

Next step is to manufacture a purpose made mandril to mount the case block on so I can then machine the front portion of the case and the front bearing housing. Photo below shows progress to date.

Now it’s off to the milling machine to start the profiling operations.

[DiogenesParticipant @diogenes]

This looks great fun.

..rather your fingers than mine..😀

[bernard towersParticipant @bernardtowers37738]

Just what I was thinking!!!

[Roger BParticipant @rogerb61624]

A carburated ‘model aircraft’ style diesel or with fuel injection ?

[dean clarke 2Participant @deanclarke2]

This project is a “standard” model aeroplane control line engine. Yes, the plan is to also build and fly an enlarged version of the aircraft ,that the original engine flew,  and fly it control line. Let’s see how we get on.

Cheers

Dean

[JasonBModerator @jasonb]

Looks good so far, hope you can hang onto the larger version!

[bernard towersParticipant @bernardtowers37738]

I would think you would need a centre post or an assistant to hang on to when you fly that. Lokking forward to it!

[Roy VaughnParticipant @royvaughn26060]

Looks like it could be a rear induction team race motor.  Or maybe a giant Comp Special for a ten foot Kandoo?

[noel shelleyParticipant @noelshelley55608]

When you come to the compression ratio you could drop it from the original as there will be less heat loss to the cylinder walls and chamber. This in turn will reduce the load on the crank and other components. Starting could be interesting. Good Luck Noel.

[dean clarke 2Participant @deanclarke2]

Hi Noel, the engine is variable compression. should be a doddle to handle.

Dean

[dean clarke 2Participant @deanclarke2]

Here’s a couple of pics of the original sized replica I’ve already built. These also were machined from solid, no castings.

 

[dean clarke 2Participant @deanclarke2]

Here’s the progress on the big boy to date.

 

[dean clarke 2Participant @deanclarke2]

Next photo.

Next up is to make the tooling up to machine in the cylinder section and then I’ll fettle it all to final shape.

 

[dean clarke 2Participant @deanclarke2]

Here’s another pic.

[DiogenesParticipant @diogenes]

Glad to see this project ‘still on the go’ 😊

[dean clarke 2Participant @deanclarke2]

Here’s the next machine step all done.

 

 

Now the fun begins.

 

[KEITH BEAUMONTParticipant @keithbeaumont45476]

All great stuff Dean. You will need to keep your fingers clear when you start this Monster up!

Keep it coming.

Keith.

[petetwissellParticipant @petetwissell]

Interesting – what was the original engine you’ve scaled up from?

[dean clarke 2Participant @deanclarke2]

The original engine this project is scaled up from is the extremly rare Pepperell 23 team race engine which can be found in Maurice polletti’s book “Those amazing Pepperell’s” I was lucky enough to get my hands on one of the original engines through a friend and that engine is what was used as the main referance for the original sized replica’s I built some time ago, photo’s of completed engine in this thread. This project is a scaled up 24cc version of that engine.

[dean clarke 2Participant @deanclarke2]

And VOILA one finished crankcase ready for the rest of the parts.

Next up is the crankshaft and the front end components.

 

[KEITH BEAUMONTParticipant @keithbeaumont45476]

That looks a superb piece of work Deane !  Keep the photos coming.

Keith.

[DiogenesParticipant @diogenes]

Nice!

[bernard towersParticipant @bernardtowers37738]

Nice work ,what are you making the crank from?

[dean clarke 2Participant @deanclarke2]

Crankshaft and cylinder liner will both be machined from 4140 steel.

Dean

[brickyParticipant @bricky]

Today I completed line boring the crankcase for the single cylinder 2 pistons and 3 con rods by Wolfgang Tepper .The crank case has 4 bearings and I used a between centres boring bar ,I made it 1mm below the 22mm bearing to reduce any bending as it a long bar This created a problem as there was a limeted chip clearance and it kept jamming until I sussed out the problem.The boreing was slow as I had to clear the chips.The bore is true but a nats wallet oversize,I will rub the bottom half on a sheet of emery paper until the bearings are nipped.Buttock clenching but I was pleased with the result ,now for the camshaft bearings.

Frank

 

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