My new project ...Diesel engine .

[Minh Thanh]

Hi All !
My new project ...Diesel engine .
a little update with new design, a lot of changes...now it looks good (hopefully)
Engine capacity 10 or 12 cc, I haven't decided yet
It is the premise for a project that I posted
https://www.modelenginemaker.com/index.php/topic,12620.0.html

[Roger B]

Are you planning this as a full diesel rather than hot bulb?

Do you have a source of 2-1 crossed helical gears for the side shaft or are you going to make them?

[CI]

Cool engine design !
 

[Minh Thanh]

Are you planning this as a full diesel rather than hot bulb?

Do you have a source of 2-1 crossed helical gears for the side shaft or are you going to make them?

Hi Roger B
I will build both types of engines: diesel (true) and Hot-bulb engine
Gears: Although I have cut some gears - of course in an "amateur" way and I really hate cutting gears. I also searched the internet for gear suppliers but I couldn't find gears of the size I wanted. So the only option: cut the gears myself.

Cool engine design !
 

Thank you ! 

[Minh Thanh]

 Hi All !
 An update
 The gearbox part for the governor is just a preliminary design to give me dimensions...which gives me an idea of ​​what to do next.

[Minh Thanh]

Hi All !
 I need help....
What is the name of the part in the picture ? How does it work ? Thanks !
 
 <a href="https://www.youtube.com/watch?v=UKScvorB85E" target="_blank">http://www.youtube.com/watch?v=UKScvorB85E</a>

[Michael S.]

Hello Minh Thanh,

I can't give you the English term right now. It's an oil pump with multiple connections. It's driven. A central oiler.

[CI]

The oiler design is interesting in that it drips upwards, apparently through liquid that does not mix with oil (water ?).

I have seen the "drip upwards through water" oilers on steam engines, but was not aware that they were used on IC engines.
I am not positive how that oiler gets the oil up and over to the various places after it drips upwards.

Here is a steam engine lubricator, which drips upwards through water in a sight glass.
The rate of oil flow can be seen throught the window in the form of the speed of dripping.
And a positive oil flow can be verified to each area that needs oiling by observing the dripping through the windows.
If one of the oil pumps stopped working, you would not necessarily be aware of no oil flow without having the windows for visual verification.

<a href="https://www.youtube.com/watch?v=SyI4wozVb94" target="_blank">http://www.youtube.com/watch?v=SyI4wozVb94</a>
.

[Michael S.]

I'm not familiar with this version with the sight glass and rising oil drops for diesel engines. I've often seen oil pumps that produce a single drop of oil; this amount can be adjusted separately, and these drops are then transported under pressure to the lubrication point by a second piston in the pump.

https://www.roesen-bremen.de/gruetzner.php

[Minh Thanh]

CI , Michael S .Thank you very much !

I'm not familiar with this version with the sight glass and rising oil drops for diesel engines. I've often seen oil pumps that produce a single drop of oil; this amount can be adjusted separately, and these drops are then transported under pressure to the lubrication point by a second piston in the pump.

https://www.roesen-bremen.de/gruetzner.php

Hi Michael S !
Actually I don't intend to build like that , everything is too small to be made to the same detail,.
I just want to do similar to the link you shared.

Update :
  ---I wish.....someone would design this engine for me...----

[Zephyrin]

here you can find 0.8 Module helical gears
they also have 0.5 Module.

https://fr.aliexpress.com/item/1005007880665661.html?spm=a2g0o.detail.pcDetailTopMoreOtherSeller.11.5961bvlgbvlgui&gps-id=pcDetailTopMoreOtherSeller&scm=1007.40196.460259.0&scm_id=1007.40196.460259.0&scm-url=1007.40196.460259.0&pvid=339a26b1-3bd8-469a-9ba6-3b66d3a344b7&_t=gps-id:pcDetailTopMoreOtherSeller,scm-url:1007.40196.460259.0,pvid:339a26b1-3bd8-469a-9ba6-3b66d3a344b7,tpp_buckets:668%232846%238110%231995&pdp_ext_f=%7B%22order%22%3A%2227%22%2C%22eval%22%3A%221%22%2C%22sceneId%22%3A%2230050%22%2C%22fromPage%22%3A%22recommend%22%7D&pdp_npi=6%40dis%21EUR%215.69%215.69%21%21%216.45%216.45%21%40211b816617642550696663249eda0c%2112000042688154987%21rec%21FR%214344569378%21X%211%210%21n_tag%3A-29919%3Bd%3A4d25a5aa%3Bm03_new_user%3A-29895&utparam-url=scene%3ApcDetailTopMoreOtherSeller%7Cquery_from%3A%7Cx_object_id%3A1005007880665661%7C_p_origin_prod%3A

another great built to follow, thanks Minh Thanh !

[Minh Thanh]

 Hi  Zephyrin . Thanks for link
I use 60 and 30 degree gears , That makes the C-C distance shorter ( see attached photo )

 Hi All .
 Update : I changed some dimensions to make it more reasonable (changing one part size will require changing the size of other parts: Crazy)
I am currently looking into installing the fuel pump
 

[Minh Thanh]

Hi All !
 Update :
....still have a lot of parts to assemble but everything is ok.
I will start buying materials and processing.

[AlexS]

Looking good! What kind of static and dynamic compression ratio are you designing?

[Minh Thanh]

Looking good! What kind of static and dynamic compression ratio are you designing?

 AlexS !
 I am not a professional engine designer so I don't know.
Compression ratio - theoretical - of the engine: 20:1

[AlexS]

me too! sounds good!

[AlexS]

The projects is interesting to follow. I have no pratical experience with diesel engine other than visit to test plant of DAF truck engine departement and VW. Which was interesting to see!

But also Roger progress and builds are interesting to follow. To realize a system for our homemade creations.

Out of the box, after deep chat with copilot maybe give a ball park idea to downscale a simple injector and delivery pump and spill port for variable quantity?. Maybe it is good idea to build a IDI indirect swirl chamber instead of DI direct. But still need high pressure at nozzle opening and pumping. Which need accurate tolerances and machining. Might interesting to outsourch critical parts far east in the world.

Might be interesting to first design and run the engine om gasoline and keep in mind to later turn to diesel. Building an Direct or indirect gasoline injection system which is less critical and prove the design. Later swapping piston/cylinder head to high compression. Gasoline is thinner and mix better with air, lower injection pressure needed and need less critical injector and pump body/piston!

Sorry I don't want to rush but this idea was in the head of couple days!

Greets

[Minh Thanh]

Sorry I don't want to rush but this idea was in the head of couple days!

Greets

Why the "sorry" !!??   Let's discuss this so everyone, including myself, understands better 

The pump doesn't need to create high pressure; the fuel injection time can be at 50 degrees before TDC, at which point the pressure in the cylinder is low.

[AlexS]

Great!

Okay I don't know exact delay or ramp angle when the cam lobe hit the maximum lift and the full open duration when there actually the needle of injector opend. What I read that aiming at 150 bar opening pressure of nozzle with very small holes (0.2-0.3mm two or more). But indeed cylinder compression pressure is far less. I could imagine that diesel is difficult to evaluate or create larger droplets under lower injection pressure. Which for model engine it would less a issue than modern emission targets. Maybe 80 bar would also be safer.

Well it would interesting to see one homemade!

[Minh Thanh]

  Hi AlexS !
For valve-type nozzles: I don't know the actual injection time.

Injection time: When the lobe begins contacting the plunger.

Lobe: After some testing, I found that straight lobes seem to inject slightly better than lobes with a curved radius.
Nozzle with very small holes (0.2-0.3mm, two or more): I haven't tried it, so I don't know. But I probably won't try it; I'll choose a simpler diameter that's feasible, inexpensive, fast... and still achieves the same result: the engine runs.

[AlexS]

Thanks for information! It is for sure a archievement that engine runs;)

[Minh Thanh]

 Hi All !
An update

[CI]

 

[vtsteam]

I don't know much about diesel engines, but the base is a beauty. How did you make it? 

[Minh Thanh]

CI , Steve . Thank you !
 A diesel engine is similar to other internal combustion engines, the only difference is that it has a higher compression ratio and fuel injectors and a fuel pump.

 

. How did you make it? 

 
  I haven't finished it yet because there are still a few holes to drill...
Here are a few pictures, hopefully they're helpful.
Just marking for sawing, milling, grinding, and a little bit of finesse.

It was made using a milling machine converted from a drill, and with a homemade l...a...t...h...e - you could call it a lathe - grinding... all of it.

[vtsteam]

Wonderful! 

I don't want to sidetrack this thread, but is there somewhere else where I can see or read about your lathe and converted drill/mill?

[Minh Thanh]

Wonderful! 

I don't want to sidetrack this thread, but is there somewhere else where I can see or read about your lathe and converted drill/mill?

Hi !
Machinery and tools are part of the machining process.

The lathe I built over 12 years ago, just a few simple things and it was a  "lathe !?".

But what's very interesting is that I built engines: Stirling, flame eater, steam, 2-stroke, 4-stroke - up to V4 and I4, and including "true" diesel engines (pump and injectors) and even an I4 true diesel engine from that lathe.

As for the milling machine: I just made the X-Y axis and assembled it onto the base of a bench drill, and it became a milling machine.
 
I'm planning to change a few things to make them better and upgrade them into an NC machine... Perhaps at some point in the future....

I recently bought a Chinese lathe (around 600 USD), which makes machining easier. However, perhaps due to habit, I usually use my homemade lathe, while the Chinese lathe, after adjustment..., I use it for tasks that sometimes require precision, such as turning long shafts or needle turning....

 some pictures for you.

[CI]

Nice work !
.

[Roger B]

A nicely made lathe    You get good results from it 

[Kim]

Wow! That's quite amazing! 

Kim

[vtsteam]

Minh Thanh, I like your lathe! It's heavy where it needs to be. And you have a boring table. I like your anti-backlash nut, too.

I've built two lathes, and I like any lathe that someone else builds and uses. Are there pics of your drill-press/mill or did I mistake one in that set of photos?

Great!!! 

[Sanjay F]

I'm amazed too, that's really astonshing that you made that and the result you have obtained are superb! 

[Minh Thanh]

  Thank you for your comments !! 
 Hi All !
 I'm back.

Reason for my absence :
- I was a bit busy.
- My computer's hard drive failed and I lost all the engine designs, which was crazy when I updated Windows 10. It's probably because the old hardware wasn't compatible with the updated software, causing conflicts... a lot of things to resolve afterwards, including redesigning this engine.
Anyway, it happened - and life goes on !

A little update :

[Sanjay F]

Sorry to hear about the loss of your engine designs, that must be tough. Glad you're back 

[Minh Thanh]

 Sanjay F , Thank you !
 
 Hi All !
A few updates:

During the design and  process, I initially planned for a sealed gearbox. After preliminary machining, I found it quite unsightly – at least in terms of size ; there was another way, making the gears even smaller – so I decided to replace it with an open gearbox: it seems to fit the engine's design best - Or at least I find it pleasing to the eye.
 

[Sanjay F]

Looking impressive .....following along 

[Roger B]

Glad to see you back on here    I agree that the open gears look better 

[Zephyrin]

 Great work Minh Thanh;
I totally understand why you want to show off those amazing helical gears, but I dare to say that I disagree—for me, a less bulky gearbox, one that gives a glimpse of the internal gears, similar to  the gearbox on the Crosley engine shown in post #5 would be more elegant and closer to reality.
Just to say, but of course this is your creation from A to Z, (including machine tools!) truly impressive.

[Laurentic]

Hi Minh Thanh, I'm a bit late to the party but on reply #5 you asked what a part on an engine was.  It is, as others have said, a mechanical lubricator.  I worked with them back in the 1960's - yes, I'm that old! - on ships main engines, they supplied lube oil to the diesel engine cylinders, lubricating the liners to help prevent the piston rings sticking in the grooves as well as generally lubricating the liners in use. 

Down in the base of the unit is a simple two diameter plunger - the difference in diameters producing the displacement areas - that pump the oil via ball suction and delivery valves.  Varying the plunger stroke varies the output.  The oil is pumped up into the glass tubes which are filled with distilled water, or distilled water and glycerine, and the tubes are fitted with a fine wire up the centre whose function is to guide the oil up to the top and out without the oil mixing with the water.  On a bank of lubricators, one glass tube for each engine cylinder, one can check all cylinders are getting the same oil delivered by checking the rate and size at which the little drops of oil are produced and ensuring the rate and size is the same in all glass tubes.  Not very technical and specific, as it's purely visual, but it works!  Plus it's a constant and easy confirmation that the cylinders are being supplied with lube oil too.  Nice to see again in your video after all these years!

Now back to the build - all coming along very nicely.  Plus loved your self built lathe too, well done.

Chris

[Minh Thanh]

Sanjay F, Roger B, Zephyrin, Laurentic
  Thank you !

 

Great work Minh Thanh;
I totally understand why you want to show off those amazing helical gears, but I dare to say that I disagree—for me, a less bulky gearbox, one that gives a glimpse of the internal gears, similar to  the gearbox on the Crosley engine shown in post #5 would be more elegant and closer to reality.

Previously, I had a solution: shorten the thickness of the crankshaft gear  (or both gears) – that would make the gearbox more suitable for the engine size. But I found an open gearbox quite interesting, anyway, 
 ----
 I also didn't think I could get this far with these so-called "machines"   
 
 

[Minh Thanh]

Hi All !
 An update :
 

[Sanjay F]

Looking amazing Minh - you've made a lot of progress 

[Admiral_dk]

I agree - looks Amazing 

Great that you were allowed to login and post today   
And sorry that other things on the Web prevent this from being easy ....

Per     

[Minh Thanh]

Sanjay F, Admiral_dk Thank you !

Great that you were allowed to login and post today   
And sorry that other things on the Web prevent this from being easy ....

Per     

I just hope it doesn't happen too often 

[PaulR]

I haven't had time to follow this thread so I'm not at all sure what I'm looking at... but I do know it looks fantastic!

[Minh Thanh]

I haven't had time to follow this thread so I'm not at all sure what I'm looking at... but I do know it looks fantastic!

Thank you !
 
 Hi All !
 I don't know if this helps, but this is how I machine the needle shaft.
 The old live center wasn't very stable, so I made a new one.

Another method is that after machining a section, I open the clamp on the rotating center support and move it in - clamp it again, and then open the clamp on the chuck and pull the workpiece out a bit - clamp it again - and continue machining.
 Hopefully this gives you some ideas.

[Roger B]

Hi Minh,

Are you using TIG welding rods for your needles?

[Minh Thanh]

Hi Minh,

Are you using TIG welding rods for your needles?

Hi Roger !
I've been a little busy, and I often have trouble accessing the forum, so I'm replying to you a bit slowly. Sorry !

Yes, I used stainless steel TIG welding rods to make the needles. (I usually use what is readily available around me.)

I want to know: "Why..." so I made a few needles with a diameter of 0.5 mm for testing, but they were mostly useless - there was a way to make it spray better, but it started to alter the texture of the whole size I wanted, so I went back to the familiar size and with few adjustments, the results were good.

  <a href="https://www.youtube.com/watch?v=6ph2MciY5WE" target="_blank">http://www.youtube.com/watch?v=6ph2MciY5WE</a>