[HN Gopher] Making tiny 0.1cc two stroke engine from scratch
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       Making tiny 0.1cc two stroke engine from scratch
        
       Author : pillars
       Score  : 141 points
       Date   : 2025-11-30 17:34 UTC (6 days ago)
        
 (HTM) web link (youtu.be)
 (TXT) w3m dump (youtu.be)
        
       | pillars wrote:
       | 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=...
       | 
       | 2. https://modelenginenews.org/midge/index.html
        
         | WalterBright wrote:
         | I still have a Cox .049 engine in the basement somewhere.
        
           | tlb wrote:
           | Of course that's .049 cubic inches (~ 0.82 cc), huge compared
           | to the one in the article.
        
             | WalterBright wrote:
             | 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 wrote:
           | Used to see adverts for those in magazines and even (iirc)
           | comic books
        
         | JKCalhoun wrote:
         | 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 wrote:
       | 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
       | 
       | > 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 wrote:
       | I just noticed that this channel has 2 million views and only
       | four videos, all from about a year ago!
        
       | wcrossbow wrote:
       | This is great. If you enjoyed it you should check
       | 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 wrote:
         | Wait but the one you linked seems to be pneumatically driven,
         | while the op one is an actual combustion engine, right?
        
           | wcrossbow wrote:
           | That's true! Sorry for not mentioning that.
        
       | antonvs wrote:
       | 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 wrote:
         | 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 wrote:
         | 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 wrote:
           | Ah thanks - I was imagining that perhaps the engine didn't
           | have high enough compression to achieve ignition.
        
         | vessenes wrote:
         | 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
        
           | antonvs wrote:
           | The spring start makes a lot of sense, thanks.
        
       | N_Lens wrote:
       | If you want to see the engine running it's at 30:12
        
       | acomjean wrote:
       | 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 wrote:
         | 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 wrote:
         | I would love to couple one of these mini-engines to an electric
         | motor and... build a cursed USB-C "generator"... ;)
        
       | jakedata wrote:
       | 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 wrote:
         | Cox 0.049?
        
         | JKCalhoun wrote:
         | Me too, brother.
        
         | mycall wrote:
         | Flick a pen on it instead.
        
           | greenbit wrote:
           | Ah, the classic "chicken stick" approach. No shame in that!
        
       | JKCalhoun wrote:
       | 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
        
       | pillars wrote:
       | 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_MQHKr2DqhfD...
        
         | echelon_musk wrote:
         | https://www.youtube.com/@thisoldtony
         | 
         | https://www.youtube.com/@Chronovaengineering
         | 
         | https://www.youtube.com/@cylosgarage
         | 
         | https://www.youtube.com/@inheritancemachining
         | 
         | https://www.youtube.com/@breakingtaps
         | 
         | https://www.youtube.com/@blondihacks
         | 
         | https://www.youtube.com/@tarkka
         | 
         | https://www.youtube.com/@dgelbart
         | 
         | https://www.youtube.com/@JoneseyMakes
         | 
         | https://www.youtube.com/@Erik-not-Eric
         | 
         | https://www.youtube.com/@Clough42
         | 
         | https://www.youtube.com/@Alecsteele
         | 
         | https://www.youtube.com/@NBRWorks
         | 
         | https://www.youtube.com/@NoEngineerHere
         | 
         | https://www.youtube.com/@StefanGotteswinter
         | 
         | https://www.youtube.com/@oxtoolco
         | 
         | https://www.youtube.com/@ROBRENZ
         | 
         | https://www.youtube.com/@MrCrispin
         | 
         | https://www.youtube.com/@Clickspring
         | 
         | https://www.youtube.com/@ArtisanMakes
         | 
         | https://www.youtube.com/@MHAnything
         | 
         | https://www.youtube.com/@Jellyfishmachine
         | 
         | https://www.youtube.com/@MakerB
        
           | pillars wrote:
           | Thank you!
        
         | johnohara wrote:
         | Have to recommend TryAlly. He makes it look easy and
         | straightforward. It's not.
         | 
         | https://www.youtube.com/@tryally
        
         | chongli wrote:
         | Thank you for the Alex Slocum link. I was aware of a lot of
         | those other machinist channels but the engineering course is
         | new to me. This looks incredible. Alex is a fantastic teacher!
        
       | Cockbrand wrote:
       | 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!
        
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