My new project ...Small diesel engine .

[peterl95124]

Minh-Thanh, nice choice of engine to model !!!

I have built a working gasoline + spark version of the Hansen Diesel, as a precursor to an actual diesel injection version (like Hansen's its all built out of silver-brazed together sheet steel), if you're curious look for "my hansen diesel" on youtube, "mostlyIC" is my current channel name.

but on to my point, I researched making my own helical gears (Hansen did) and never found a method that I liked (the best IMHO is George Fellows' design, George Britnell has plans for it, if you insist on home made), so I bought gears, even that took some searching, finally found 45-deg helical gears in 48-DP with teeth of 15, 20 and 20, 30, from rpcgears.com in UK ===> so I designed the engine around those gears <===

Also, it looks like you're using a worm gear up top, that means the vertical shaft is spinning really fast, that means the gears at the bottom (crankshaft) have to be step-up rather than step-down, but if you experiment with skewed helical gears you'll find this isn't practical, they will have too much friction and won't move without undue force or simply won't move at all. that's why my choice of gear teeth are reduction gears at both the top and the bottom, and they run very smoothly without any unnecessary friction.

anyway, I'm really looking forward to seeing how you design and implement fuel pump and injector for your new engine, I might want to copy to avoid doing my own time consuming experimentation (getting old and lazy !!!)

 

[Vietti]

Peter, Tried your gear link and it did not work??

 

[peterl95124]

Peter, Tried your gear link and it did not work??

check out the youtube video of my #1 engine, also here's a photo of parts for my #2 engine, if you want me to help debug your design I'll have to know more about it ?

 

[Vietti]

Sorry, I meant to say I could not get the link, rpcgears.com, to work. No bugs yet.

 

[peterl95124]

Sorry, I meant to say I could not get the link, rpcgears.com, to work. No bugs yet.

my bad :-( its hpcgears.com !!!

I had been using sdp-si.com here in USA for decades but they aren't being reasonable about a 15-T helical in this DP as they only stock going down to 20-T even though 15-T doesn't require special cutters and fits the hub size they use (they gave me a quote that's not fit to print), so I'm using HPC Gears in UK now.

 

[minh-thanh]

Hi @peterl95124
About gears, I will test...check..
The reason I chose the gear ratio on my engine is because it brings symmetry, neatness... to the cylinder head.
About fuel pump, it is similar to the cylinder engine pump, just the structure has been changed to suit the new design.
injectors, after some experiments with 1-cylinder and 4-cylinder engines, I will follow the new style
What information do you need about them ??

Hi All !
An update .
I used a "HM-CNC 100-axis machine " ( runs on rice ) . A little sanding makes it look nice and gives me more interest in the project

 

[petertha]

I have built a working gasoline + spark version of the Hansen Diesel, as a precursor to an actual diesel injection version (like Hansen's its all built out of silver-brazed together sheet steel), if you're curious look for "my hansen diesel" on youtube, "mostlyIC" is my current channel name.

This probably isn't the appropriate post to discuss, but I checked out your YouTube & saw your nice running engine. Is your build documented somewhere? I'd love to see the parts. I was under the impression the Hansen diesel secret sauce was closely guarded information. Men in dark suits might knock on your door soon, LOL. Anyways, I just finished Audible of this book & I kind of have diesel on the brain. Miniaturization seems like a formidable challenge, so my hat is off to you guys.

https://www.simonandschuster.com/bo...-of-Rudolf-Diesel/Douglas-Brunt/9781982169909

 

[minh-thanh]

. I was under the impression the Hansen diesel secret sauce was closely guarded information. Men in dark suits might knock on your door soon, LOL.

Yes, very secret , "strange and different" from my engines

 

[kuhncw]

Your engine frame is a nice looking design.

Chuck

 

[minh-thanh]

Hi All !
An update
After aligning and drilling, threading..., I assembled and placed them on the base plate. After re-measuring the base plate, I discovered it was 5mm smaller in width. Because I bought it a long time ago, I didn't know am I wrong or the is store wrong !?, so I will buy 2 other base plates .

 

[peterl95124]

This probably isn't the appropriate post to discuss, but I checked out your YouTube & saw your nice running engine. Is your build documented somewhere? I'd love to see the parts. I was under the impression the Hansen diesel secret sauce was closely guarded information. Men in dark suits might knock on your door soon, LOL. Anyways, I just finished Audible of this book & I kind of have diesel on the brain. Miniaturization seems like a formidable challenge, so my hat is off to you guys.

https://www.simonandschuster.com/bo...-of-Rudolf-Diesel/Douglas-Brunt/9781982169909

Peter,
my plan is to document the build process here on HMEM, and sell plans at cost only since this is a rip-off of Hansen's B.E.A.Utiful design (converted to imperial). this will most likely happen before I get a true diesel working, which means its possible that one of you will figure it out before I do (or so I can hope !!!)

I got an email channel with Finn Hansen going by sending him a link to the video of my running Rolls Royce Merlin model engine, but I don't want to put that connection in jeopardy by asking him about his secret sauce, that we're going to have to figure out on our own !!!

would love to see you join in on this design exploration.

Peter.

 

[Steamchick]

"Secret sauce" for diesel running?
I learned some years ago that DERV has a constituent (that unique "sharp" smell of fresh DERV) that is the "instant-flash/low-ignition-point constituent to help DERV ignite rapidly under cold starting, etc? Once warm, the base oil works fine. Otherwise starting can produce "white smoke" which upsets the emissions regulators...
So in order to simulate that for used "MacDonalds' chip-fat", or other used vegetable cooking oil, you should add a coffee mug of "paint thinners" (Turpentine substitute), to every gallon of vegetable oil. The trace of "Turps Substitute" - with a lower "flash-point" then starts the combustion when the fuel is injected in the engine, helping to maintain reliable and clean combustion when cold.
So maybe the "secret sauce" has some Turps. substitute in it? - Or Paraffin? Or Hydraulic oil? (But that has horrible corrosive effects in some applications - despite a very low flash point!).
You are only looking for 2~5% of additive in the base oil. - possibly less?
Winter/Cold/Alpine climate DERV has less wax in the oils than "Summer", or "Mediterranean" climate DERV - according to my Oil company Chemist.... but that doesn't affect cold starting.
K2

 

[minh-thanh]

This probably isn't the appropriate post to discuss,

No problem .
Discussions will help me and others learn more, It's okay to be a little out of line

 

[peterl95124]

"Secret sauce" for diesel running?

sorry about the confusion, the term "secret sauce" in this context is a euphemism for Hansen's secret designs and machining techniques for achieving a working injector and pump, didn't intend to mean a literal liquid, again, sorry !!! (he's making no secret about his fuel: "Fuel: Kerosene, mixed with 2 % two-stroke mineral engine oil." from his website)

 

[Steamchick]

And there was I about to send this tome...
Found this:


More on "secret fuel" for diesel. I heard the "half Kerosene and half lamp-oil".
Also: With Diesel fuel - "a lot of smoke and little power". This is indicative of too little heat at ignition, to properly vaporise the injected oil. Fuel pump pressure too low, injector orifice too large, actual compression ratio too low, or something. Heavy oils take more energy (Heat) to reduce droplet size small enough for complete combustion in the short time available inside the cylinder. The heat comes from the compression "work". Both compressing the air (heat to ignite and vaporise droplets), and the pressure developed before the injector on the fuel line (work to shear the fluid into fine droplets against the surface tension of the fuel). -Kerosene has a lower surface tension than "fuel oils".

Also I know a gas turbine guy advocated up to 50% Petrol in Kerosene as "cleaner" due to his model gas turbine having a lower compression ratio than a full sized engine, and difficulty making the pre-heater stage for the fuel/air mix adequate for full Kerosene oil. - but he said the actual mix ratio was around 50:50, but had been tuned a bit for preventing odd flame conditions... He used Propane-air as the starting mix for his turbine to get the combustion chamber and pre-heating zone hot enough for stable running on wet fuel.

Wasted,,,
The Joke is on me (as usual). Ho! Ho! Ho! - Happy Christmas one and all!

K2

 

[minh-thanh]

With the engine's 20-1 compression ratio, it was not easy to start it, but he turned the flywheel "simply and slightly", moreover to achieve the auto-ignition temperature of kerosene. - about 210 degrees Celsius is not easy and I don't think with that rotation the air temperature in the cylinder will be difficult to set at 100 degrees Celsius

 

[Steamchick]

I wonder if he introduces a squirt of "easy-start" (Ether) into the fuel, as a tiny amount has such a low ignition temperature that it starts aero engines of around 1cc - or less - at much lower compression ratios. ?
On a works' van, the heater circuit was NG, so in winter we always started it with a squirt of Easy-start. Even when the can was nearly empty, the smallest drop taken in to the air intake was adequate, at down to -10C when the van had been outside all night. Otherwise it was a lot of kettles of boiling water or a blowlamp on the intake manifold to warm the air intake to get it to start!
K2

 

[minh-thanh]

Confidential informations , sometimes it makes it difficult for newcomers to understand, making it difficult...for building a diesel engine
In general, some information is different from my engines. ..Or at least with mechanical ( the plunger stroke is 0.03mm) , or the theory of self-ignition temperature of kerosene is 210 degrees Celsius.

 

[TonyM]

I'm not convinced by the video. I imagine that when he restarted there was a fair bit of original fuel in the pipework and even some in the bottom of the tank despite the ''bleeding''. That takes nothing away from his fine engines even if they are normally running on higher grade fuel.

 

[minh-thanh]

The truth is that when I started building diesel engines, his videos were a source of inspiration but the more I watched, the more I learned,...... the more .....I didn't understand about the pump, about the fuel, about the ratio. compression ..and then the self-ignition temperature of diesel and kerosene is about 210 to 220 degrees Celsius, I don't understand even more.
All the engines we did or have been making we must follow the principles of full-size engines. For example, in a 4-stroke engine, we can change the compression ratio from 4, 5, 6, 7...10 -1 but it requires has ignition somewhere 15 degrees before TDC. With a diesel engine, we must comply with its principle that the temperature of the compressed air in the cylinder must reach the self-ignition temperature of the fuel we use.
Can I say my 4-stroke engine with 9-1 compression ratio can run on its own without ignition?? that is crazy
Can I say my diesel engine can run with an air temperature in the cylinder of 50, 70, 90 degrees Celsius, when using diesel or kerosene?? Do you believe ??
All the engines that we did we just copied and scaled them but they have to follow the principles of full size motors. We can do the best we can with what we have on hand and we will never, ever... never, ever...achieve technical standards of a full size engine, with a full size diesel engine and new, when we cold start it there will always be smoke.