I Tried 3D Printing a Gas-Powered Engine!

[@CamdenBowen]

To try everything Brilliant has to offer-free-for a full 30 days, visit brilliant.org/CamdenBowen . The first 200 of you will get 20% off Brilliant’s annual premium subscription.

[@xmysef4920]

Damn now you’re getting sponsors too! Nice video aswell, I like seeing you return to different projects!

[@EliasSilva-ff7us]

I noticed you put the negative connection for the spark plug after the circuit breaker, it should be placed before it. Love your channel.

[@vitorstreetboys]

será que a deformação material esta alterando o ponto?

[@fabiotiburzi]

why not two stroke? i mean you have to make the piston interfere with the cylinder but it's worth a try due to semplicity

[@ItsRandy420]

Maybe try acetylene for your fuel. Definitely shouldn't have any problems with ignition lol

[@Jorged18]

Bro you have no idea how excited I was for this update

[@Drosba]

We all were.

[@been9ne991]

SAME

[@mattteprot]

SAME

[@peter9011]

Honestly

[@abdullahajeebi]

Yippee!!!

[@guerrillaradio9953]

I've thought of replicating something similar to this using Ford's plastic engine research from the 80s. Basically, they made the main block and head structure of PA6 glass filled Nylon (which is 3d printable), but made steel inserts for the cylinders, bearing surfaces, combustion chambers, etc. It worked fairly well from what I've read. With 3d printing, you could then easily print in water cooling passages, etc, so that even if on a hot day, the coolant temp gets too ~100C, it's still lower than the glass transition temp of Nylon (and that's plain Nylon with no fiber reinforcement).

[@elitewolverine]

If you have a resin printer you can use 3dmaterials HDT resin, which holds its shape for up to 264C temps. Which should be good enough for this simple low rpm design

[@nvcnc]

Torlon! I'm curious as to what happened with that project. from the articles I read, it worked reliably during a full endurance race, weighed next to nothing in comparison to a metal counterpart, and had some promise with regards to costs. Even if it was more expensive, it seemed to fade from existence.

[@dappermanphoto]

I'd be curious if the heat in the engine compartment could've potentially created a problem they didn't expect. Or expansion played a variable and they gave up. Would love to see it re-tested with today's technology @@nvcnc

[@HurricaneLantern]

electroplating the whole block might work too

[@dappermanphoto]

@@HurricaneLantern Potential yeah, I'm not sure if the coating would be thick enough to create any type of extra stability though

[@tilen3266]

I need to see this thing run. Its so promising. You inspired me to buy a 3d printer and print a air engine. Took 3 attempts but it actually ran before the crank exploded

[@CamdenBowen]

Welcome to the club!

[@bethpostlewaite7017]

If it did run it would melt because it’s plastic😭

[@tilen3266]

@@bethpostlewaite7017 nope its resin so in terms of wear. And it ran for like half our before the crank gave up

[@edvinjohansson9625]

Hi! Someone with knowlege on smaller engines here! Weak spark is because you're opening the points WAY too far. They should open like 0.4mm or something along those lines. Try it, you'll get better spark. Right now you have great spark when just using the screws as electrodes, but under compression the spark will fail. The second large fault with this engine is the compression. I've never seen an engine run on less than 5 bar compression, and that 5 bar engine ran like hot garbage. You should aim for a minimum of 6 bar. 7-10 bar is usually considered good in most smaller engines, but 10 bar in a plastic engine would probably not work. Fueling isn't as important as you think. If you remove the carb from your lawn mower and just pour a bit of gas into the intake, it WILL start. It won't run, but It'll start. An engine needs a good precise mix of air and fuel to run good, but as long as there is both air and fuel in the chamber, it will fire. As long as there isn't enough fuel to foul the plug that is.

[@skycloud7623]

Resistor plugs could be the problem too?

[@t3cht098]

yeah this is what i was thinking 2 bar is so low for a engine (i'm use to work on car engine as a mecanic so i was not sure about little engine) but i think he need around 10 bar because i never seen a engine run under 10

[@ncrshane1919]

I don't have a lot of experience on small engines, but on full size auto engines anything under 100psi (6.5 bar) and it won't even try to fire on that cylinder, granted that threshold is probably very fuel dependent. Also gonna second the spark breaking down at pressure, at the 25ish PSI he is over double atmospheric pressure so the spark can only jump half as far. The spark plugs should work, its like he has an issue with the grounding of the plug or something with how weak the spark was. Something else I wonder about is how much fuel is actually getting into the cylinder. With the current setup you are taking fuel in the form of butane and mixing it with air from the venturi, and then by having a gap to the velocity stack you are creating a second venturi that is pulling in more air, leaving you with a very lean A/F mixture that is likely below the combustion threshold. It also leaves a gap for the A/F mixture to flow away from the intake valve and not get drawn into the cylinder. That could be why it was giving 1 attempt to fire when slowing down, enough butane built up in the cylinder to become flammable. I would mount the venturi directly to the intake port on the head with the velocity stacks on the side air inlets. That would basically form an intake manifold with port injection, giving a richer A/F mixture and helping ensure the mixture actually gets drawn into the cylinder. Edit: Just did the math, he aimed for a 6:1 compression ratio, but a peak PSI of only 29 means he effectively is only getting a 2:1 compression ratio. A 6:1 compression should yield 80 - 90 PSI (5-6 Bar).

[@CamdenBowen]

Seems like I got plenty of work to do! Thanks!

[@edvinjohansson9625]

@@CamdenBowen No problem! Love watching you try to design these little engines. I've made a few compressed air engines myself on the 3d printer, but we're building them quite different. Currently designing an inline 2 with aluminium cylinder sleeves and rubber o-rings as piston rings (inspired by your engines). All previous designs I've made have just had plastic on plastic, and zero compression. Also giving it exhaust valves instead of just ports as I've been using until now.

[@thebestmaidens]

I am so invested in this series. In 8th grade I did a presentation on how the internal combustion engine works and have been so interested in the mechanics of making a miniature one. This series is essentially what I want to do just someone actually doing it and knowing what they're doing. I love it!

[@esahg5421]

you already a genius, show the others a working transmission and clutch. easy to understand but looks extremely complicated.

[@nebo37]

Super underrated channel. Big fan of your work , keep going

[@dronemotionlab]

right?! he is very smart i just realized it too and saved the vid and channel .

[@CamdenBowen]

Thanks bro!

[@blackburngaming8345]

"It's not even that hard to make an engine, just SUCK, SQUEEZE, BANG, BLOW." ayo WHAAAAAA

[@wilurbean]

Keep up the work man I was working on a 3d printed machine that needed to spin at 10k rpm with a heavy magnet. 11 revisions (full redesign) for a functional prototype over a year. You got this. Keep at it.

[@AviationAngler]

Damn 10k is wild

[@gwheyduke]

You could put a metal sleeve in the cylinder to make it more durable. Also on starting, I've had success using a flywheel extension about 2-1/4 inches in diameter on the engine and a two-inch wooden dowl on a 5/16 -inch steel rod in the drill. A large O ring from a water filter cap drives the engine. This was you can continually crank over the engine with one hand, allowing the other hand free to tweak needle valves and so on.

[@iLife64]

"What's under the hood?" "IDK, I downloaded it lol"

[@aserta]

18:26 not just a funnel, Coanda effect plays a huge rule. The air curves around the lip, so in fact, the totality of the air is much greater than what's "funneled" in. It goes beyond the lip, which is why v-stacks suck in hot engine bays, because even if you point the thing in the fresh air, it will suck air from a far greater area due to the properties of fluids (of which air is one). So you end up sucking a hell of a lot more hot air than cool air (because the air travels straight from the fresh air port is smaller than the greater volume created by the lip) and the engine suffers. The best stacks are exposed stacks, hence why vintage racers had them out to atmosphere.

[@SocktheWorm]

Thanks to KZbin's terrible algorithm, I'm watching this 'series' in reverse order.

[@Sierra-579]

Thought of doing this myself recently, glad to see I wasn't the only one 😅Keep it up man! I really like the diagrams too.

[@hayden3928]

Making awesome progress! Congratulations on getting a video sponsor!

[@CamdenBowen]

Thank you for being a long time viewer!

[@SaintHarper-t2h]

​@@CamdenBowenyou should try a two stroke engine it would help oil and lubricate and no valves required

[@ogKEGGY]

I actually just put a printed velocity stack on my 2 stroke scooter, and I couldn't believe how much of a difference it made. I had to jet up like 6 sizes over what I was at already. Velocity stacks are sick.

[@olfreal]

Super underrated channel! The best series on KZbin!! I cant wait to see an update!

[@dbk24601]

8:52 to 10:07 is an absolutely amazing description. after just going over magneto and battery ignition systems in class this really helped for reinforcement

[@m1sst4k37]

21:00 try to use starting fluid/carb cleaner, it starts anything if it have ANY little compression and good spark - it will start

[@markl3871]

I was SO excited to see you made another video on this. Looking for someone who 3d printed an engine is how I found your channel. Its awesome.

[@glabifrons]

A few things... Spark plugs have a small gap as they need to spark under compression. The denser the medium, the more difficult it is for a spark to jump the gap. I'd suggest making the bolt ends a bit closer together, as even a lawnmower with it's low compression is going to have a gap on the order of 0.030". It looks like it was kicking back when it was firing, which means your timing is way too far advanced. Try a bit after TDC to start with... that should make it a lot easier to start. Butane isn't a bad idea at all. I'm tempted to suggest propane as it should be a lot easier to use a propane torch for this, but it might burn hotter, shortening the usable life of the engine. I'd add some grease (not necessarily oil) to your cam lobes. Once this thing does work, they're likely to flatten out quickly.

[@tombuster]

The compression you managed to create is very impressive! Excited to see what you come up with to make it run! Also glad to hear that other cars shed parts, too! I was afraid it was just mine that did that... Congrats on getting a sponsor too! Great to see your channel grow so rapidly!

[@CamdenBowen]

Thank you for the support!

[@christianbjerkestrand2315]

I actually do alot of repair on older engines that use a similar ignition system. Your cam for the points are opposite. If you got a small raised point you get more presise ignition and the coil gets a longer contact period to charge up. Also the cam height seems to big and can easily cause float at higher rpm, especially due to the cam design. Also most car coils are actually 9v and require a ballast. They are 9v to make starting a car engine easier when the voltage drop while cranking over. Giving the coil 12v will fry either the inside or the points. Some coils have an internal ballast, but many require an outside ballast.

[@hunnybunnysheavymetalmusic6542]

Use an open bowl 'whisker' carburetor. Its really simple, will not flood, and will allow your engine to take in just as much as it needs. The simplest way to make one is to: 1, just take a metal baking pan [needs to be fuel proof and flame resistant in case you get a backfire from the timing being off], and 2, take a piece of sheet metal, put an inlet at one end [preferably the corners actually to make the flow and efficiency best] and outlet at the other, and 3, loosely fluff some coarse steel wool in between those. It can be held together with wire, tape or rubber bands, and you can fill it from the inlet using a funnel or just being careful enough to not spill all over the place. This is a dry vapor carburetor, and therefore will not dissolve your plastic [that we can then leave to the heat of combustion to take care of], and it can not flood, nor thin your oil out too much. Also it won't carbon foul anything [NOT that a plastic motor of THIS kind of plastic would last that long] if it ran for a long time. From there, just connect a hose from the outlet of the carburetor to the inlet of your motor. I can't suggest you use glass cookware, simply because it is glass and can break, but if one did want to see how much fuel was inside the carburetor, one could solder tubing, or thread in some hose barbs and put a clear vinyl tube on the side to act as a sight gauge. It would be best to seal the edges of the box with a little silicone, but only if you make sure not to spill fuel on the silicone sealant, because it can soften the silicone and make it swell up and ruin the seal. A small 9 inch pan would be fine for this. Technically you COULD use a round cake pan, a bread pan, even a normal cook pot, and a cook pot even comes with a handy removable lid [again, best not to use one made of glass in case of a backfire] that would be super easy to observe, and, a thick aluminum pan would allow easier threading of hose barbs in the sides than thinner steel would. These have existed a long time and work really well on stationary engines. They are not quite so great on vehicles where tipping over can be a problem, nor on engines where high horsepower can be a problem, but just for the sake of youtube content, it will work on this instance, and last longer than your engine. Another thing I can mention here is that if you do not mind 'cheating' enough to use various sizes of smooth walled cans [either soda cans, beer cans, or even single operation die formed aerosol cans] you might be able to insert a piston sleeve, a cylinder head combustion chamber, and a metal surfaced piston, which would allow much longer and smoother operation. The trick would be to find one cylinder for the head and sleeve diameter [they have to match, but could be cut using 2 separate cans to ensure adequate material to make them match] and then one slightly smaller for the piston. I know there are some out there, I have made little 'air motors' out of them long time ago when I was bored.

[@kepofshangri-la8942]

A youtuber who loves laminar natural aspiration as much as me? And he also does stupid projects combining 3dp and internal combustion engines? You might actually be my favorite KZbinr.

[@CamdenBowen]

Thank you! And if you like this project... then you will certainly want to see the next video coming out soon :)

[@Electromagneticdestruction]

You need a small capacitor and a ballast to get a useable output from the ignition coil, hope this helps for future experiments:)

[@srboromir452]

If energy is stored in the magnetic field of the transformer what does the capacitor do?

[@Electromagneticdestruction]

@@srboromir452 It eases arcing on the contacts and resonates back and forth with the tranformer when they open to create a higher energy pulse or spark at the output.

[@umiy6299]

also, he needs to make sure that the contacts aren't bouncing too hard, or else there will be a lot of "noise" in the switched line and that may make the spark weaker due to the breakdown not being clean

[@Electromagneticdestruction]

@@umiy6299Correct :)

[@Hans-fq4ip]

The issue with the spark plugs may be the internal resistor that helps limit Radio Frequency (RF) noise. May be too high of a resistance for the current/voltage generated by the low speed of the engine. That would explain why 2 bolts seemed to work better.

[@LISITCODM]

I love watching this guy inventing stuff that shouldn’t be made but doing it anyway because it’s cool😎 good work my guy

[@davidtucker1155]

i really like your paper headgasket especially since i have this 1980s suzuki quad that i fixed with some paper as a gasket for its leaky clutch cover and it still works today!

[@MotorizedMayhem]

a plane 0:05

[@danielarobbins]

I know nothing of engines and love these videos. Keep up the great work.

[@5APPH_13]

Hey Camden, loved the video, I do have some ideas you could try. Try going back to a DOHC so you can adjust the intake/exhaust separately. Changing to a domed piston to allow the compression to force on the piston more than the cylinder walls, maybe try a 2 cycle system with a motorcycle style ignition system, and a sealed case for motor oil.

[@Impossible_Fishy]

I’ve been looking forward to this video! Nice work man

[@play4dayzproductions347]

Make a 3d printed block, crank, piston, and cylinder. Then put a metal sleeve in the cylinder with metal piston rings! Cool stuff! Keep up the good work, God Bless!

[@excell211]

I think it would be possible to make a 3D printed gas-powered engine if you used the 3D prints for molds for casting heat resistant composites (or even metals, such as aluminium). Also, I think it would be interesting to use a *semi-adiabatic piston design* (it was used on diesel engines), basically, you make the piston head partially hollow and inject air and fuel in a vortex inside this piston hole. Since a lot of heat ins't actually being exchanged with the piston head, it makes the engine more efficient, but it also reduces the amount of heat generated. Plus, I would also advise you to take a look at hypocycloid engines, these kinds of engine try to reduce the friction of the piston head with the cylinder walls by making it a straight movement converted to rotary movement using gears. *If you get the parameters correctly*, I think that _maybe_ it could help this engine a little more of a life-span by using linear bearings. Well, there are a lot of different ways you could try to make this 3D printed engine work, be more efficient and/or durable, but I don't know how much you want to crack your head on the subject.

[@Strider314]

loved that bit around 9:00 where you replicated those old tv explanations. gold.

[@leeboatt]

Camden is by far my fav youtuber at the moment. Super underrated.

[@laszloszell8753]

I made a working 3d printed engine,with water cooling. What I made different is: 1. In the engine block I used from aluminium pipe (40mm ID) a Cilinder liner,so the plastic won't melt and also you can cooling it. 2. In the block I designed channels for water flow cooling the aluminum wall(coolant passages). 3. I used a hall sensor and a little magnet for 50cc fuel injector. You easily can adjust the timing with this setup. You can burn Aceton or anything very flamable just keep under some pressure for the injector.

[@kodykeye]

FINALLY!!! I've been waiting for you to post this video since I found your channel!! Thank you and great job on the engine!

[@billywilson3285]

You are incredibly smart my guy. You got a gift for sure

[@MichaelCowden]

Really enjoying all your videos. The engineering walk-throughs are great. Also love the video quality, editing and humor, and especially the outdoor demonstrations. These are super cool projects. Keep 'em coming!

[@albelab3d]

This channel, and of course you, are fantastic!! You can drive the user through every single minute of your video, by talking and showing what you are doing in a unique way that everyone can understand!! Thank you so much! Keep up with this good work!!

[@pneumantic6297]

The issue has to be the amount of pressure that the butane is getting as it goes into the engine. When the piston is moving up and down that quickly I highly doubt it is pulling enough butane inside in order to create actual combustion. Try grabbing an air compressor and tune the pressure on one of those blow air gun handles with butane spraying into a metal tube of the air gun. Make sure that you are getting a good amount of butane in there, and then have it shoot directly inside. It just needs more flow and pressure so I am sure you can do this by just shooting in the hole like what you did with the makeshift venturi but with pressurized air rather than ambient air (assuming you dont just backflow the butane hose). Of course this is a guess but I would say its worth a shot considering you basically have everything available to do it.

[@typicalconservative9994]

When you shaved the piston flat you increased cylinder displacement causing a longer compression stroke therefore raising compression to around 7:1 or 8:1 which would cause a higher torque and hp output if at the same revolution- Your favorite diesel mechanic

[@migamer15]

I'm thanking you for your hard work trying to make a 3d printed gas engine and i wish for every project you have to be successful

[@NissanSkylinegtrr32]

Finally you did an update and i am looking 100% forward to it, hope you make another soon i love it please and dont stop i need to see it start, even for 2rotations until it blows up, im looking into doing it myself and if you would sell/share the models afterwards i would 99% start building my own, thanks for keeping this series alive❤❤

[@Akhin-zx]

LETS GO ANOTHER COMBUSTION ENGINE VIDEO

[@CamdenBowen]

W

[@avkrpen]

If you make the gap on the ignition system smaller. You know the light switch that you used. That can make a huge difference in starten and running a engine. If the gap is smaller the rpms can go higher. I have a old 50 cc engine where the gap is 0,6 mm.

[@trabi601enjoyer]

For the fuel system, i'd use a petrol vapors. You can make the system by having a closed jar of petrol with two pipes, one leading from outside to the bottom of the jar submerged in petrol, and the second one leading from the top of the jar to the intake. Good Luck!😅

[@AgentOrange96]

KZbin says I've watched this video already. Not sure why. But it actually looks super interesting so I'm totally down to *actually* watch it.

[@jevfot4526]

2:03 jump scare omg 😂

[@nextlet8410]

Like, there's no any other ytber I wait so much for his videos

[@incomplete628]

You could try to build a 2 stroke engine, i know you need to time the exhaust and intake holes to make it run, but it could be interesting how a 3d printer handles the intake hole.

[@tburda823]

The algorithim brought me here, and I'm so glad it did. DUDE you were SO CLOSE! It's definitely your fueling system. I'd love to see you design your own FI system (Or carb to start for simplicity) and make it run. You could try a very small fuel system from an RC car or maybe small gas power tool to prove the concept before designing your own? Awesome project man glad I found your channel today.

[@TheEngineeringDutchman]

Yes mate!!! you sir just made it to the list of my top 10 favorite youtuber, just because of.... you

[@kbee225]

At this point I'd be happy to see a compressed air engine with 3D printed plastic.

[@RoboBuildsBMS]

how does this channel not have a million subscribers yet?

[@Gunbudder]

my friend is a mechanic and he told me the only "life hack" he ever used working on engines was to use a Cheerios cereal box material to make air intake gaskets for small engines. he would stack up three or four layers of that material and cut the gasktet shape and then use that

[@manganeseheptoxide7825]

Love the update on the series. I think you should give butane another chance, I think your mixture was too lean. If you decide against it, maybe try using a carb from a lawnmower or a chainsaw, get the thing working on that and then go to making your own. Too many variables!

[@aserta]

18:16 i think that if you drill holes, tiny holes around the lip, the vacuum stops forming. I'm not 100% sure of this, but there's some old military intakes i've seen over the years that were straight pipes (with the knowledge that they would fully know about intake shape properties, especially on account of NACA - which transformed into NASA) that had these tiny holes.

[@jacobhorton7850]

Bruh, wheres your patreon, I have some paper that's pulling my pants down, seriously tho man, your pumping out some top tier quality KZbin vids that are up there with some other makers like Integza, Tom Stanton and Project Air to name a few, thank you for your content and I truly hope only your engines will suffer burn out. Keep it up!!!

[@turvboi007]

This guy deserves way more subs

[@roscoe454]

a condenser in line with a old style car coil is needed and the car coil runs on 9 volts but when it cranks over its 12 volts..hopes this helps ..and the condenser is on the neg side of the coil 👍👍

[@Sludge73]

Seems like LP would be easier to deal with than Butane. Especially considering availability of regulators, valves , and orifices in the world. Great project. I hope to see more

[@kbee225]

You could keep the butane cyclinder in a warm water bath to help keep it warm for longer. Or use a industry-grade gas cyclinder thats 4 feet tall.

[@marioredondo8279]

To prevent the cilinder from excesive fricción and having to print the entire engine each time you could try to insert a metal or plastic sleeve, like a piece of thin wall pipe cut to the length of the stroke and with the inner diametre of the bore. Maybe a pvc or copper pipe

[@gwheyduke]

That's a good idea

[@Copperdude]

"i was just driving and then these white bits just fell out" 💀 quote of the century

[@megamanguy]

3:29 alot of ignition coils have a low ohm resistor in series with them to avoid burning out the primary

[@dieguerrero]

Try lowering the compression ratio by shimming the cylinder head. The issue is that your valves and piston probably don't have a good enough seal to keep the mixture in the compression chamber. Lowering the compression ratio will help keep some mixture in the chamber because it will be at a lower pressure

[@henningklaveness7082]

Interesting project. I have some relevant experience, and will be very interested to see how long this runs once you get it going. A few thoughts: - Try to use as many COTS components as possible to begin with, even if your long term goal is to 3d print everything. This especially applies to ignition and fuel metering systems. That way you can concentrate on solving one problem at a time. - The engine is obviously under fueling (running lean) as it is. That's probably the main reason it won't idle. You need a fuel metering device of some sort, or you will never get anywhere. For the sake of simplicity, a carb is probably the way to go. - Likewise, look into using a self contained CDI system off an outboard or similar. They usually need only 12V and a hall effect signal to work, and are both powerful and reliable. - The comrpession pressure seems really low compared to the compression ratio, about half the expected value. You either have some kinda design flaw or a major leak somewhere. - Thermal management is going to be your limited factor once this gets on idle, especially at the piston crown and exhaust valve seat. These components rapidly approach the melting point of various metals in "real" engines, and there is only so much you can do by reducing compression and running rich. Consider using different materials in these areas, at least initially, so that engine life can be extended far enough to gather useful prototype data. Good luck 🙂

[@milksheihk]

There was a fully Zytel Nylon engine in the 80s, it even powered a LeMans entry, was a 4 cylinder, loosely based on(well molded from) the 2 litre Ford(Europe) Pinto engine block.

[@hunterpratt9963]

Great videos man, thanks for sharing! Generally a gasoline powered engine has a much higher compression when at top dead center, something like 100-125psi. It allows for better thermal efficiency and to extract all the energy from the fuel. Another important part is having your air fuel ratio as close to stoichiometric as possible, this ratio changes depending on fuel type. In an open atmosphere the Venturi works for mixing the air to a relatively stoich ratio but may need a more tightly held ratio. Hope you can get that thing running! Maybe try a fuel that burns "cool" in the sense that it dosnt produce as much heat from combustion, alcohols tend to burn cooler.

[@jadenwebb8651]

that compression when tested is achieved through building the pressure over multiple strokes. An engine with a compression tester may reach 150psi but will only increase by 60psi or less each stroke, depending on the health of the engine and the compression ratio.

[@Joshuabwd40]

This is actually really cool lad imagine putting it on a go kart

[@bryanadams3353]

Use a spray can of carb cleaner with the long plastic tube (this will fire up a standard engine) spray paint your head gasket with hi-heat paint. Fuel timing/ignition timing on the compression stroke. That "snap" may have been a back fire lighting up your exhaust...I'll mind my own biz now

[@I.no.ah.guy57]

I enjoy your videos and the things you make, especially because im a mechanic. Looking forward to seeing what else you build in the future. Oh and just a quick note about sparkplugs, you can change the spark gap yourself by just bending that little metal finger. You can get a sparkplug gapper/checker (most commonly looks like a 50 cent coin) and it helps you bend that finger up or down and set the gap. I know you didnt end up using the plug, but you wouldnt have had to buy a new one unless it burns out

[@simona625]

Try a piston with two O-rings wide enough apart to add stability to the piston. Less possibility of waggle = less piston on cylinder wear. Only the O-rings will have contact with the cylinder, but you will need to find a way to lubricate between the O-rings. This mod should also help with the air engine too

[@jackfarrell1369]

You should consider adding an oiling ring to the piston to prevent it from gouging the cylinder wall. And some smoothing and crosshatching on the cylinder walls wouldn’t hurt.

[@dooby1445]

Hey, if you can’t get the 3D printed version to work, you could look into using what you currently have and “PLA lost wax” cast it! You can build a cheap furnace, go grab a cheap iron/aluminum engine block at the junkyard, cut it up and metal it, and cast it. It’s what I’m currently working towards.

[@lukasohlsen5885]

i was 23 sec into the vid and can already tell that this guy is so underrated

[@Madkite]

As I used to do ignition systems, I can't tell you about the plugs. The issue is most spark plugs and plug leads today are suppressed. This means they have loads of resistance. Enough to turn the fat blue snappy spark, in to a pathetic weedy dull puuufffttt. This stops it interfering with radios. But also means the mixture has to be just right. You need unsupress spark plugs and lead. So there's basically 0 resistance. This is why old radio generators and aircraft leads have shelding as you need unsuppressed lead and plugs as you shouldn't have suppressors on magnetos. Anyway this is why modern cars have coil packes. They do the same sheldong trick without all the lead and distributors so you can have a big fat hot spark and invite a weker mixture. The gap is dependent on a few things, but largely compression. The gap is silly small in open air. But under compression there's maybe many times the air in that gap. So many times the resistance to the spark. Making that tiny spark a bright thing as it burns through the thick air. Make the gap too big and on a normal engine the spark may jump to another post in the distributor cap and jump a cylinder not under compression. And that's just getting the ignition right before you start on the rest. Not simple at all.

[@3v068]

I cant wait to see another update. I love this series.

[@henrybene7319]

using 2 O-rings on either end of the piston should prevent the piston slap, and if you designed a longer intake pipe with helical blades to circulate the air, you could probably atomize a liquid fuel well enough to prevent it from eating away at the engine's internals

[@JessePlays3434]

Glad you're trying again!

[@joshconfer209]

Really cool way to recreate a point system, distributor and fuel injection system. I do wonder if you could have just gapped the spark plug wider.

[@SuperVALUEDCUSTOMER]

i would reccomend the piston ring, cylinder, exhaust valve and seat and crank out of metal at least. the piston can probably be printed. A metal cylinder slid into the block then figure out lubrication, for now a little oil in the gas and reuse the ignition off the old motor you copy from. it might work

[@rodrigo1468]

Maybe the weak spark is bc of the amount of resistance in the plug. There are some plugs without resistance like for example in a 2stroke (I know the engine is a 4stroke) u can get a b8es or br8es. The "r" is for resistance and the "8" is the heat range. (Goes from: 2 hotter to 10 colder)

[@xmysef4920]

Hey Camden Perhaps it may also be your fuel flow-rate? since it does seem like most of the combustion happens when it’s *almost* at a standstill, which might be a sign that it either isn’t getting enough fuel (or fuel-air mixture) or perhaps something is messing with your ignition. The fact that it only fires when it has almost stopped does tell a few things though, so keep that in mind

[@mumblety]

you're making me want to design my own 3d printable engine.

[@TheJunky228]

i would bet good money that the spark plugs you were trying had built-in resistors. if you had used a non-resistor sparkplug you’d have gotten a good spark like the two screws

[@michaelfortier7726]

what's the approximate ignition timing you're running? something around 15 degrees before TDC should give you the best chances at starting it. Also, try using a small plenum to properly mix the butane and air. Lastly, you tried at atmospheric pressure in the soda bottle, but the electric resistance of the air inside the engine goes way up when the pressure increases. You might not be igniting anything once it's compressed. Try sticking an oscilloscope on it to see if you're actually igniting.

[@CamdenBowen]

I had messed around with the timing and found if it were too soon, it caused it to backfire like in the clip where it destroys the crankshaft. Using a method to monitor spark is genius however

[@Frank.and.Gus.]

bro called out subaru, probably the funniest thing ive heard today

[@CamdenBowen]

It's nuts that they built a car that loses oil pressure when turning right

[@Frank.and.Gus.]

@@CamdenBowen lol, it's so true

[@Unicorn-Vibes]

Compression testers also have a one way valve in them so that you can turn over the engine and it automatically records the highest of the strokes compression.

[@jadenwebb8651]

many of the issues you where having with the spark plugs is likely due to using a resistor type plug, all modern spark plugs are resistor plugs to cut back on EMI. Due to the plug having a resistor the coil does not need to be as big, having an oversized coil will cause great voltage for forming the spark but a weak spark due to low amperage. That is one of the reason the coils on modern cars is so much smaller than older vehicles.

[@Whistlindiesel1500]

This is just my dream but I have no idea of cad so I can’t do this. I would love to see it run and also if you were to share the stl‘s

[@DanB-0]

The biggest reason the sparkplug didn't have good spark was because it didn't have good ground, in a normal metal engine the head and the rest of the engine act as the ground. So when power goes down the stem it jumps the gap to the little tail of the nut (ground) but by itself is not alot of ground which ia why when sparkplugs are tested for spark they are typically held up to the side of the motor giving it the needed ground. If you're familiar with the acrilyic head videos you will notice they wrap a piece of wire around the base of the plug before inserting it which the wire gets connected to suitable ground.

[@twichbars8531]

Loved this so much I been waiting a long time

[@jamest.5001]

The engine idles because of the weight of the flywheel, it keeps it rotating! You should dip the 3D print in plaster, allow ig to dry for a few days, thf place it in a vacuum chamber for a week, to be sure all water is out, thrn heat the chunk of plaster to melt out thd plastic, then go to a salvage yard, or recycler, geta aluminum car rim, or pistons, a cast aluminum part, and get a propane weed burner, and a micro oxygen /mapp gas torch kit, and refractory cement, and a metal trashcan, use a small copper tube to to drip oil into the flame of weed burner, if the aluminum isnt burning allow the oxygen and mapp gas to flow into weed burner, within 30 minutes the aluminum should be thin as water, ready to pour from the crucible , the best way to build a engine , us to buy a bicycle motor piston, cylinder, and crank and rod, design the crankcase to fit these parts, maybe use two cylinders, a whole engine can be biught fir just over $120, ready to run, the build quality is poor, it needs to be disassembled and cleaned thoroughly, abd reassembled . With any luck at all, getting a machine shop to make a coupling, to connect the cranks together should be easy, just remember, a two stroke needs the crank case for each cylinder seperated from the other cylinder !the crank case is the intake for the engine,

[@nukeboy7633]

your timing might actually be off for the butane, cause its not firing at the right time in the stroke, you want just after the apex then goes down into the exhaust stroke, try feeling for the air coming out the exhaust when tuning it, that's all i can rack my brain around for it not working

[@NateSchoonoversAdventures]

I have been working on a 3d printed airsoft minigun. Having trouble getting compression in a cylinder. What did you do to get any compression? Is the cylinder lined? Is it printed horizontally? Did you use any particular settings? Cool project!

[@CamdenBowen]

I forgot to mention this but I used an acrylic pipe as a cylinder lining. It has a smooth surface and when combined with an O ring causes low friction and an air tight seal

[@notserpmale03]

This is so sick waiting for the next part