24cc DIESEL ENGINE FROM SOLID

[dean clarke 2Participant @deanclarke2]

Here we have the cylinder blank machined from solid 2 1/4″ bar stock 4140 steel.

Next mission is to machine in the ports, then we’ll be onto the honing and final lapping of this monster.

Until next time

Dean

[KEITH BEAUMONTParticipant @keithbeaumont45476]

Thats a lot of swarf made , Dean. All looking very smart. Looking forward to seeing it finished.

Keith

[dean clarke 2Participant @deanclarke2]

Thanks Keith, I’m slowly getting there.

Dean

[dean clarke 2Participant @deanclarke2]

OK so finally been able to machine the ports into this giant cylinder liner, so here’s the latest update.

next step is to finish lap the cylinder and make it ready to take a piston and contra. At 32mm bore that’s going to be an interesting task.

Here’s a quick look at the cylinder test fitted into the rest of the crankcase assembly.

 

 

After lapping the cylinder I’ll start on machining up the components for the compound piston assembly.

Until next time,

Dean Clarke

[DiogenesParticipant @diogenes]

That’s a big cylinder! Best wishes with the lapping, looking forward to more..

[alecsParticipant @alecs]

My fingers still hurt when I think of flick starting my McCoy Redhead 10cc 50 years ago. 24cc is a beast!!

[dean clarke 2Participant @deanclarke2]

Well now that the cylinder liner is all lapped and ready for the piston and contra to be fitted up I’ll take a small break and start on the cylinder head. Head is machined from a piece of solid 3″ 6061 T6 ally bar.

Here’s how it starts………..

This should be interesting, lol

Dean

[dean clarke 2Participant @deanclarke2]

In the meantime, I had to make some con rods for another project so I decided that it would be a good time to make the rod for the big boy while I was at it.

Now lets get some work done on the piston assembly.

Dean

[dean clarke 2Participant @deanclarke2]

Well, here’s the progress to date. compound piston assembly is all finished and assembled, and then fitted up to the rest of the engine.

Now i’ll make the compound contra piston assembly and then go back to the cylinder head.

Not far from finished now……..

Dean

[alecsParticipant @alecs]

Totally awesome work. Respect.

[dean clarke 2Participant @deanclarke2]

Compound contra piston assembly all made and fitted to the cylinder liner.

Now we just need the cylinder head finished and the compression screw.

Dean

[DiogenesParticipant @diogenes]

What’s the contra compounded from?

[dean clarke 2Participant @deanclarke2]

Contra piston components are made from cast iron, compound meaning not 1 piece but an insert plug with a the movable compression adjuster inside. both parts are lapped and fitted to each other and the cylinder for a gas tight seal.

Dean

[KEITH BEAUMONTParticipant @keithbeaumont45476]

Hi Dean,  Brilliant work. I would be interested to know why the contra is in several parts,compared to the normal one piece?

Keith.

[dean clarke 2Participant @deanclarke2]

Hi Keith, the contra piston assembly in this engine is made in 2 parts because at 32mm bore a single contra would prove a bit awkward to make and fit(which is of course possible) but more importantly the compression adjustment is too severe. using the 2 piece setup give a much better running adjustment with finer compression adjustment, much like the setup on the Jeffe ETA 15 team race engine.

Dean

[KEITH BEAUMONTParticipant @keithbeaumont45476]

Thanks for the explanation, Dean.

Keith.

[dean clarke 2Participant @deanclarke2]

Here’s the next update on the machining of this big boy diesel engine.

Start of the cylinder head, a lump of 3″ round 6061 t6 aluminium bar stock.

After the first stages of machine work……..

And the outside done……..

Next step is to machine the profile into the fins and then the exhaust slots.

Dean

[dean clarke 2Participant @deanclarke2]

OK so I’ve finally managed to find some time to finish off the cylinder head and compression screw for this engine.

Compression screw…….

And all assembled ready for the test stand…….

Now all we need is the fuel bottle..

Dean

[DiogenesParticipant @diogenes]

I look forward to your finding it..

[KEITH BEAUMONTParticipant @keithbeaumont45476]

And the “Chicken Stick”!  What level of compression pressure has your lapping method  achieved Dene?

Keith.

[KEITH BEAUMONTParticipant @keithbeaumont45476]

Evey time I see this Crankcase,I marvel at your carving skills. Absolutely Brilliant!!

Keith.

[dean clarke 2Participant @deanclarke2]

Hi Keith, no chicken stick mate just quick hands, lol I hope.

Compression is variable so the compression ratio is also very “adjustable”. The piston has been lapped with lead in on the crown and skirt taper to allow for good oiling of the piston to liner faces. I have also machined in 2 small oil retention grooves in the compression band of the piston to help alleviate seizing under operating temperatures which can be a very serious problem for large lap seal piston/liner assemblies.

Next mission is to build a suitably solid test stand to run him up on.

Until next time

Dean

 

[dean clarke 2]

On dean clarke 2 Said:

Next mission is to build a suitably solid test stand to run him up on.

 

Dean

 

And bolt it to the floor!?

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