[My Design] - 1 Cylinder 4 Stroke

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Leucetius

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Moinmoin (I'm from germany ;D )

as one might remember from my introduction I am a mechanical engineering student and I'm about to graduate as B.Eng in 3 months.
During my studies I've put all I learned into my own IC engine design and this is finalising too. Sadly I've no chip making experience but 3 weeks on a CNC lathe and mill. So I' m eager to get your feedback about my design and if you would change something in respect of fabrication.

Some facts:
- bore x stroke: 22 x 22 mm = 8,36 cm³ (about 0,51 cu in)
- 4-cycle, pushrod/rocker actuated
- compression about 5,5:1

At the beginning I intended to design a gasoline not a methanol engine. But during the process I was told, that a gasoline engine this size won't run very well if at all.
So I reduced the compression (it was at some 8:1), designed the cylinder head for a glow plug and gave no thought about ignition.

As one can see on the last attached picture, the camshaft consists of a left and a right half and the helix gear. The idea is to put the gear onto one half and then press the other half in. But I've no idea how to make sure the timing isn't off or how to set it up in the first place (together with the gear).

Another thing are the needle bearings on the rod (between piston and crankshaft). The manufacturer says, all surfaces the needles run onto have to be hardened and grinded. For the shaft there's no problem as it has to be hardened and grinded anyway. But i don't know about the inner surface of the rod. Is it really crucial for an engine this size, which isn't about to run 24/7 or is it sufficient to ream and maybe hone the surface?

Ah one thing that may lower you interest: I may be granted to use our university's lathe and mill but I don't know when I have time to do so. Bachelor thesis, Master thesis and a nine week seminar paper are my top priorities until september next year. Find someone who's willing to build the prototype is way to much to hope for.


Edit: more drawings to follow (as said - bachelor thesis ;) )

Assembly_2.JPG


Mechanics.JPG


Camshaft.JPG
 
Looking good.

A methanol glow-plug ignition needs a compression between 8:1 and 8.5:1 to run ....

Although I'm not sure - do you have a way to adjust the valve clearance ? .... If what I think might be adjusters, how are they locked ?
 
After one very nice PM with question about the rest of the drawings, I realized that a recent hardware crash and the change of system that followed, has claimed another victim: My 1 cylinder was thrown back to a state where I didn't even had rockers modelled - let alone the camshaft and gear drive...
As I still didn't call a machine park my own, I doubt that I follow the path of recreate the parts I have drawings published for and do the rest from that point.
If you (like cwkelley75) like my design so far, you are hearby free to use my published drawings as you like. I may even upload the files I have so far (they don't work with the published parts 100% but may inhere suggestions) if someone wishes me to do so.

I'm mourning the loss of my files as I was proud of my creation ... even if it was just virtual.

Greetings
 

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