24cc DIESEL ENGINE FROM SOLID

[Kiwi BlokeParticipant @kiwibloke62605]

Impressive!

I’d love to know how you carved the crankcase where the ‘horizontal’ and ‘vertical’ cylindrical surfaces meet (does that make sense?), and also the internal corners where the web meets the crank extension housing.

[dean clarke 2Participant @deanclarke2]

Great care and dexterity, some fairly simple milling operations and a bunch of elbow grease,blood, sweat and the odd tear. lol.

[Kiwi BlokeParticipant @kiwibloke62605]

Thanks. As I feared, no magic machining solution then, but the application of greater-than-average skill! And patience…

[dean clarke 2Participant @deanclarke2]

Unfortunately yeah, the last part is the filing and fetteling of the cylinder to case join.

Dean

[dean clarke 2Participant @deanclarke2]

Slight sidetrack to complete the drum type back plate,

[dean clarke 2Participant @deanclarke2]

Now I’ll start the crankshaft, lol

Dean

[DiogenesParticipant @diogenes]

Can’t wait to see it, your posts here are great punctuations in the year..

..is there an induction stub to attach to the drum housing?

[noel shelleyParticipant @noelshelley55608]

Looks Good ! The crank case finish looks like a type of blasting ? What medium ? Noel.

[dean clarke 2Participant @deanclarke2]

Hi Noel, case is blasted with garnet.

Hi Diogenes, yes there is a screw in venturi that will go into the drum housing the same as the smaller original size engine shown earlier in this thread. I haven’t machined in the hole and thread for it yet.

Dean

[dean clarke 2Participant @deanclarke2]

Here’s the backplate all finished and ready to get assembled onto the rest of the engine.

[dean clarke 2Participant @deanclarke2]

Here’s the first stage of the crankshaft machining.

End of the first machining operation.

[dean clarke 2Participant @deanclarke2]

End of the first machining operation.

Now it’s time to make the special fixture to machine in and finish the big end journal.

 

[dean clarke 2Participant @deanclarke2]

And here’s the finished crankshaft.

Next up is to assemble the crank into the case and start the prop driver and spinner nut.

 

[KEITH BEAUMONTParticipant @keithbeaumont45476]

You have made a lot of swarf there ,Dean. Super work! Keep at it.

Keith.

[dean clarke 2Participant @deanclarke2]

Next step is to assemble the finished crank into the crankcase and start on the front end.

Now we move onto making the prop driver, collet and spinner nut.

And all fitted up to the rest of the engine.

 

OK so now it’s starting to look like an engine at least, been a bit of a long road so far but making progress, albeit slowly, lol

Now I’ll start on the rear end with the end cap and drum valve.

 

[KEITH BEAUMONTParticipant @keithbeaumont45476]

What sort of bearing/s have you got for the crankshaft Dean?

Keith.

[dean clarke 2Participant @deanclarke2]

Hi Keith, the crankshaft runs on twin ball bearings. Rear bearing is a 15x28x7 and the front bearing is 15x24x5.

The drum valve is also mounted on twin ball bearings, 20x37x9 in the front and 20x 32 x7 in the rear.

Dean

[KEITH BEAUMONTParticipant @keithbeaumont45476]

Hi Dean, looking forward to see this beauty finished !

Keith.

[Roger BParticipant @rogerb61624]

Looking good 🙂

How did you turn the crankpin, a block with an offset hole?

[dean clarke 2Participant @deanclarke2]

Hi Roger, the crankshaft big end was machined using a purpose made fixture to hold the crankshaft. The tooling I made for this job is designed so that I can machine any crankshaft with a 30mm stroke in the same fixture without any setup time involved and also with the repeatable accuracy needed for accurate machining each time I use it.

Dean

[Roger BParticipant @rogerb61624]

Thank you, I use a Keats quick set angle plate for crankshafts. It doesn’t give an instant setting but is quite versatile.

[KEITH BEAUMONTParticipant @keithbeaumont45476]

My normal method for I/C engine crankshafts is to use a Stevensons ER25 ,4 sided collet block. This is centred in the 4 jaw, then moved horizontaly sideways for the radius of the stroke dimension.

Keith.

[dean clarke 2Participant @deanclarke2]

Hi Keith and Roger, both of those systems are perfectly adequate for one off operations and work extremely well. My situation requires a bit more complexity due to the significant increase in numbers of parts being made that’s why I use purpose made tooling to remove all the setup time involved.

Here I have finally be able to finish the back plate assembly parts.

And here they are all final assembled.

And test fitted to the rest of the engine to ensure they play nicely together.

Now it’s onto the piston liner assembly.

Dean

[dean clarke 2Participant @deanclarke2]

Here we have the venturi and needle valve assembly all finished and fitted up to the rest of the engine.

 

Next up is to make the cylinder liner and piston blanks.

Dean

[Grindstone CowboyParticipant @grindstonecowboy]

Looking good!

Rob

[Author]

Posts