5 ms·

Making tiny 0.1cc two stroke engine from scratch

155 points by pillars 11mo ago

pillars 11mo ago
Some Model Engineering related resources: 1. Engineering drawings of small model engines used for model aircrafts. They are designed for manufacturing and working, not not like showcase item. We can actually build them. https://outerzone.co.uk/plans.asp?cat=Engines&Xcardsperpage=48 https://outerzone.co.uk/plans.asp?cat=Engines&Xcardsperpage=... 2. https://modelenginenews.org/midge/index.html https://modelenginenews.org/midge/index.html
- WalterBright 10mo ago
  I still have a Cox .049 engine in the basement somewhere.
  - tlb 10mo ago
    Of course that's .049 cubic inches (~ 0.82 cc), huge compared to the one in the article.
    - WalterBright 10mo ago
      I also had an .020 engine, but it never ran very well, and I don't know what happened to it. I had a lot of fun designing my own airplanes and flying them with the .049. Modern electric airplanes are too easy.
  - greenbit 10mo ago
    Used to see adverts for those in magazines and even (iirc) comic books
- JKCalhoun 10mo ago
  Outerzone is a great site for (mostly vintage) model aircraft plans. Cut my fingers up many times as a kid trying to start Cox model airplane engines…
xseer 10mo ago
I went down a rabbit hole lately and found this article on tiny diesel engines built throughout the past decades, most of them model engines: https://modelenginenews.org/techniques/minid.html https://modelenginenews.org/techniques/minid.html > I've seen collectors turn a greenish blue and stammer out crazy offers on sight of my 0.1cc Nano, pictured here. But as the size goes down, construction difficulty and criticality of "fits" goes up exponentially.
jiggawatts 10mo ago
I just noticed that this channel has 2 million views and only four videos, all from about a year ago!
wcrossbow 10mo ago
This is great. If you enjoyed it you should check https://www.youtube.com/watch?v=8IEGmD_aV3w https://www.youtube.com/watch?v=8IEGmD_aV3w . Next to that it’s child’s play. That’s a whole trasatlantic’s engine room from scratch.
- WanderPanda 10mo ago
  Wait but the one you linked seems to be pneumatically driven, while the op one is an actual combustion engine, right?
  - wcrossbow 10mo ago
    That’s true! Sorry for not mentioning that.
antonvs 10mo ago
I skipped some bits of the video so probably missed this, but: in the beginning he mentioned no spark or glow plugs and said “similar to a diesel”, but in the end that didn’t work and he had to resort to a glow plug. Did he mention what fuel he was using for the compression-only attempts? If not actual diesel, it seems like he would have had to use ether or something like that.
- Frenchgeek 10mo ago
  He did: It was just warm enough for the ether in the mix to evaporate long before it reached the engine, so it couldn't run.
- RossBencina 10mo ago
  It was a mixture of ether, castor oil, and something else. He theorised that the ether was boiling off in the tank before it made it to the engine.
  - antonvs 10mo ago
    Ah thanks - I was imagining that perhaps the engine didn’t have high enough compression to achieve ignition.
    - CamperBob2 10mo ago
      I would think there would be some interaction between the carburetor air intake and the propeller right next to it. Intentional feedback, maybe, to change the mixture as the RPM goes up? If not intentional, then it sounds like a potential showstopper.
- vessenes 10mo ago
  https://modelenginenews.org/techniques/minid.html https://modelenginenews.org/techniques/minid.html Mentions that this engine needs a spring start and 50% ether and it runs up to 40k rpm(!) seems like it’s finicky, which makes sense given its size
N_Lens 10mo ago
If you want to see the engine running it's at 30:12
acomjean 10mo ago
Last century I was gifted a gas powered model helicopter with one of these small gas engines. It had a propeller would fly up, run out of gas and fall back down (it had some larger blades to slow its decent). You started by spinning the propeller and letting it spring back. How I didn’t loose a finger… They’re remarkable little devices.
- noefingway 10mo ago
  Brings back memories from childhood. I used to build and fly model airplanes (by wire not rc). Starting those engines was also a challenge. I still have a scar on one finger from an engine kicking back when trying to flip the propeller.
- kotaKat 10mo ago
  I would love to couple one of these mini-engines to an electric motor and... build a cursed USB-C "generator"... ;)
  - DoctorOetker 10mo ago
    I would also like to try that some day, but theres little information on efficiency. I'd also like to see one running on laughing gas (N2O), as the autodecomposition reaction is nitrogen and oxygen gas, in similar proportions to atmosphere. But the reaction efficiency would have to be high enough or I'd feel bad about the GWP.
jakedata 10mo ago
The second I heard that engine fire it was 1986 in my brain again. I could smell the fuel and feel the finger damage from repeatedly trying to get the darned thing to start. Followed by damage on the other side of the finger when it actually did. Ouch.
- jaredhallen 10mo ago
  Cox 0.049?
- JKCalhoun 10mo ago
  Me too, brother.
- mycall 10mo ago
  Flick a pen on it instead.
  - greenbit 10mo ago
    Ah, the classic "chicken stick" approach. No shame in that!
JKCalhoun 10mo ago
Related? Blondihacks [1] has been working through machining a live-steam powered scale locomotive. Has it been three years now? She easily has another year of work ahead of her before she has live, rolling stock. Wild dedication to a project that could perhaps consume half a decade of your life. [1] https://www.youtube.com/@Blondihacks https://www.youtube.com/@Blondihacks
pillars 10mo ago
Sorry for offtopic, I want to share, Some Machining related channels on youtube: this old tony, Chronova engineering, cylo's garage, inheritance machining, breaking taps, blondie hacks, tarkka, dan gelbert, Jonesey Makes, Eric(with a K), Clough42, Alec steele, NBR Works, Not An engineer, Stefan Gotteswinter, oxtoolco, ROBRENZ, MrCrispin, Clickspring, Artisan Makes, MH Anything, Jellyfish machine,Maker B, And also there is great course on precision engineering by Alex slocum: https://m.youtube.com/playlist?list=PLksE8LDXGXl_MQHKr2DqhfDC64W7QHjxL https://m.youtube.com/playlist?list=PLksE8LDXGXl_MQHKr2DqhfD...
- echelon_musk 10mo ago
  https://www.youtube.com/@thisoldtony https://www.youtube.com/@thisoldtony https://www.youtube.com/@Chronovaengineering https://www.youtube.com/@Chronovaengineering https://www.youtube.com/@cylosgarage https://www.youtube.com/@cylosgarage https://www.youtube.com/@inheritancemachining https://www.youtube.com/@inheritancemachining https://www.youtube.com/@breakingtaps https://www.youtube.com/@breakingtaps https://www.youtube.com/@blondihacks https://www.youtube.com/@blondihacks https://www.youtube.com/@tarkka https://www.youtube.com/@tarkka https://www.youtube.com/@dgelbart https://www.youtube.com/@dgelbart https://www.youtube.com/@JoneseyMakes https://www.youtube.com/@JoneseyMakes https://www.youtube.com/@Erik-not-Eric https://www.youtube.com/@Erik-not-Eric https://www.youtube.com/@Clough42 https://www.youtube.com/@Clough42 https://www.youtube.com/@Alecsteele https://www.youtube.com/@Alecsteele https://www.youtube.com/@NBRWorks https://www.youtube.com/@NBRWorks https://www.youtube.com/@NoEngineerHere https://www.youtube.com/@NoEngineerHere https://www.youtube.com/@StefanGotteswinter https://www.youtube.com/@StefanGotteswinter https://www.youtube.com/@oxtoolco https://www.youtube.com/@oxtoolco https://www.youtube.com/@ROBRENZ https://www.youtube.com/@ROBRENZ https://www.youtube.com/@MrCrispin https://www.youtube.com/@MrCrispin https://www.youtube.com/@Clickspring https://www.youtube.com/@Clickspring https://www.youtube.com/@ArtisanMakes https://www.youtube.com/@ArtisanMakes https://www.youtube.com/@MHAnything https://www.youtube.com/@MHAnything https://www.youtube.com/@Jellyfishmachine https://www.youtube.com/@Jellyfishmachine https://www.youtube.com/@MakerB https://www.youtube.com/@MakerB
  - pillars 10mo ago
Cockbrand 10mo ago
As someone who always thought that it'd be cool to create my own parts and components by milling, but who never actually had access to a milling workshop, I find this video extremely satisfying to watch. Thank you!
noufalibrahim 10mo ago
"The compression seems a little off". I'm really curious what kind of background and knowledge the creator of that video would have to develop instincts like that.
- tkfoss 10mo ago
  Work with few engines and you ll hear most of problems right away

155 points by pillars 11mo ago

Some Model Engineering related resources: 1. Engineering drawings of small model engines used for model aircrafts. They are designed for manufacturing and working, not not like showcase item. We can actually build them. https://outerzone.co.uk/plans.asp?cat=Engines&Xcardsperpage=48 https://outerzone.co.uk/plans.asp?cat=Engines&Xcardsperpage=... 2. https://modelenginenews.org/midge/index.html https://modelenginenews.org/midge/index.html

WalterBright 10mo ago
I still have a Cox .049 engine in the basement somewhere.
- tlb 10mo ago
  Of course that's .049 cubic inches (~ 0.82 cc), huge compared to the one in the article.
  - WalterBright 10mo ago
    I also had an .020 engine, but it never ran very well, and I don't know what happened to it. I had a lot of fun designing my own airplanes and flying them with the .049. Modern electric airplanes are too easy.
- greenbit 10mo ago
  Used to see adverts for those in magazines and even (iirc) comic books
JKCalhoun 10mo ago
Outerzone is a great site for (mostly vintage) model aircraft plans. Cut my fingers up many times as a kid trying to start Cox model airplane engines…

xseer 10mo ago

I went down a rabbit hole lately and found this article on tiny diesel engines built throughout the past decades, most of them model engines: https://modelenginenews.org/techniques/minid.html https://modelenginenews.org/techniques/minid.html > I've seen collectors turn a greenish blue and stammer out crazy offers on sight of my 0.1cc Nano, pictured here. But as the size goes down, construction difficulty and criticality of "fits" goes up exponentially.

jiggawatts 10mo ago

I just noticed that this channel has 2 million views and only four videos, all from about a year ago!

wcrossbow 10mo ago

This is great. If you enjoyed it you should check https://www.youtube.com/watch?v=8IEGmD_aV3w https://www.youtube.com/watch?v=8IEGmD_aV3w . Next to that it’s child’s play. That’s a whole trasatlantic’s engine room from scratch.

WanderPanda 10mo ago
Wait but the one you linked seems to be pneumatically driven, while the op one is an actual combustion engine, right?
- wcrossbow 10mo ago
  That’s true! Sorry for not mentioning that.

antonvs 10mo ago

I skipped some bits of the video so probably missed this, but: in the beginning he mentioned no spark or glow plugs and said “similar to a diesel”, but in the end that didn’t work and he had to resort to a glow plug. Did he mention what fuel he was using for the compression-only attempts? If not actual diesel, it seems like he would have had to use ether or something like that.

Frenchgeek 10mo ago
He did: It was just warm enough for the ether in the mix to evaporate long before it reached the engine, so it couldn't run.
RossBencina 10mo ago
It was a mixture of ether, castor oil, and something else. He theorised that the ether was boiling off in the tank before it made it to the engine.
- antonvs 10mo ago
  Ah thanks - I was imagining that perhaps the engine didn’t have high enough compression to achieve ignition.
  - CamperBob2 10mo ago
    I would think there would be some interaction between the carburetor air intake and the propeller right next to it. Intentional feedback, maybe, to change the mixture as the RPM goes up? If not intentional, then it sounds like a potential showstopper.
vessenes 10mo ago
https://modelenginenews.org/techniques/minid.html https://modelenginenews.org/techniques/minid.html Mentions that this engine needs a spring start and 50% ether and it runs up to 40k rpm(!) seems like it’s finicky, which makes sense given its size

N_Lens 10mo ago

If you want to see the engine running it's at 30:12

acomjean 10mo ago

Last century I was gifted a gas powered model helicopter with one of these small gas engines. It had a propeller would fly up, run out of gas and fall back down (it had some larger blades to slow its decent). You started by spinning the propeller and letting it spring back. How I didn’t loose a finger… They’re remarkable little devices.

noefingway 10mo ago
Brings back memories from childhood. I used to build and fly model airplanes (by wire not rc). Starting those engines was also a challenge. I still have a scar on one finger from an engine kicking back when trying to flip the propeller.
kotaKat 10mo ago
I would love to couple one of these mini-engines to an electric motor and... build a cursed USB-C "generator"... ;)
- DoctorOetker 10mo ago
  I would also like to try that some day, but theres little information on efficiency. I'd also like to see one running on laughing gas (N2O), as the autodecomposition reaction is nitrogen and oxygen gas, in similar proportions to atmosphere. But the reaction efficiency would have to be high enough or I'd feel bad about the GWP.

jakedata 10mo ago

The second I heard that engine fire it was 1986 in my brain again. I could smell the fuel and feel the finger damage from repeatedly trying to get the darned thing to start. Followed by damage on the other side of the finger when it actually did. Ouch.

jaredhallen 10mo ago
Cox 0.049?
JKCalhoun 10mo ago
Me too, brother.
mycall 10mo ago
Flick a pen on it instead.
- greenbit 10mo ago
  Ah, the classic "chicken stick" approach. No shame in that!

JKCalhoun 10mo ago

Related? Blondihacks [1] has been working through machining a live-steam powered scale locomotive. Has it been three years now? She easily has another year of work ahead of her before she has live, rolling stock. Wild dedication to a project that could perhaps consume half a decade of your life. [1] https://www.youtube.com/@Blondihacks https://www.youtube.com/@Blondihacks

pillars 10mo ago

Sorry for offtopic, I want to share, Some Machining related channels on youtube: this old tony, Chronova engineering, cylo's garage, inheritance machining, breaking taps, blondie hacks, tarkka, dan gelbert, Jonesey Makes, Eric(with a K), Clough42, Alec steele, NBR Works, Not An engineer, Stefan Gotteswinter, oxtoolco, ROBRENZ, MrCrispin, Clickspring, Artisan Makes, MH Anything, Jellyfish machine,Maker B, And also there is great course on precision engineering by Alex slocum: https://m.youtube.com/playlist?list=PLksE8LDXGXl_MQHKr2DqhfDC64W7QHjxL https://m.youtube.com/playlist?list=PLksE8LDXGXl_MQHKr2DqhfD...

echelon_musk 10mo ago
https://www.youtube.com/@thisoldtony https://www.youtube.com/@thisoldtony https://www.youtube.com/@Chronovaengineering https://www.youtube.com/@Chronovaengineering https://www.youtube.com/@cylosgarage https://www.youtube.com/@cylosgarage https://www.youtube.com/@inheritancemachining https://www.youtube.com/@inheritancemachining https://www.youtube.com/@breakingtaps https://www.youtube.com/@breakingtaps https://www.youtube.com/@blondihacks https://www.youtube.com/@blondihacks https://www.youtube.com/@tarkka https://www.youtube.com/@tarkka https://www.youtube.com/@dgelbart https://www.youtube.com/@dgelbart https://www.youtube.com/@JoneseyMakes https://www.youtube.com/@JoneseyMakes https://www.youtube.com/@Erik-not-Eric https://www.youtube.com/@Erik-not-Eric https://www.youtube.com/@Clough42 https://www.youtube.com/@Clough42 https://www.youtube.com/@Alecsteele https://www.youtube.com/@Alecsteele https://www.youtube.com/@NBRWorks https://www.youtube.com/@NBRWorks https://www.youtube.com/@NoEngineerHere https://www.youtube.com/@NoEngineerHere https://www.youtube.com/@StefanGotteswinter https://www.youtube.com/@StefanGotteswinter https://www.youtube.com/@oxtoolco https://www.youtube.com/@oxtoolco https://www.youtube.com/@ROBRENZ https://www.youtube.com/@ROBRENZ https://www.youtube.com/@MrCrispin https://www.youtube.com/@MrCrispin https://www.youtube.com/@Clickspring https://www.youtube.com/@Clickspring https://www.youtube.com/@ArtisanMakes https://www.youtube.com/@ArtisanMakes https://www.youtube.com/@MHAnything https://www.youtube.com/@MHAnything https://www.youtube.com/@Jellyfishmachine https://www.youtube.com/@Jellyfishmachine https://www.youtube.com/@MakerB https://www.youtube.com/@MakerB
- pillars 10mo ago

Cockbrand 10mo ago

As someone who always thought that it'd be cool to create my own parts and components by milling, but who never actually had access to a milling workshop, I find this video extremely satisfying to watch. Thank you!

noufalibrahim 10mo ago

"The compression seems a little off". I'm really curious what kind of background and knowledge the creator of that video would have to develop instincts like that.

tkfoss 10mo ago
Work with few engines and you ll hear most of problems right away