Carbon Fiber Inside the Engine - How CF rods and pistons change engines and why you can't have them
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- čas přidán 16. 05. 2024
- Let’s say that you want a car part that’s strong. Something that needs to consistently and reliably survive massive forces. How massive, well, let’s say around 100.000 newtons. But how much is a 100.000 newtons…..well to put into perspective an average person like myself can throw a punch with a force of about 1000 newtons. An average sledgehammer blow is around 5.000. So 100.000 newtons is 20 times stronger than a sledgehammer blow. And that's roughly the force to which engine internals are subjected thousands of times per minute when the engine is revving and under load.
To ensure that connecting rods can survive the violent loads inside the engine we usually make them from steel. But sometimes we also make them from aluminum. Now steel is strong. A high grade alloy like 4340 steel can survive a load or stress that is equivalent to nearly 75.000 newtons exerted on every square centimeter of the part before breaking apart. Aluminum isn’t as strong and even high grade alloys like 6061 or 7075 can only manage a maximum of 55.000 newtons per square centimeter. Now carbon fiber is completely is in a league of it’s own….it can survive 250.000 newtons per square centimeter before breaking.
Now here’s the interesting thing we actually put rods from the weakest material here, aluminum, into the most extreme engines out there which generate the highest loads and have the highest chances of destroying their internals. Why? Well that’s because aluminum is lighter than steel.
But aluminum plays a price for it’s low weight and the price is longevity. So with metals we have to compromise, we can either have low weight OR long life, we can’t have both. Now let’s look at carbon fiber again. Just like it blows steel out of the water in terms of strength it blows aluminum out of the water in terms of weight.
So carbon fiber is the absolute champ? It’s super strong, it’s super light and it has no real fatigue life issues. So if it’s the best material out there why are there zero mass produced engines with carbon fiber internals and zero aftermarket carbon fiber rods you can purchase today? I mean we make wheels, car chassis, spoilers and so many other things from it. Why not engine internals if they offer so many benefits?
Here’s the first issue. Carbon fiber does not exhibit isotropic properties. When a material is isotropic it exhibits pretty much the same mechanical and thermal properties in all its parts.
For example this block made from steel is equally strong everywhere. Applying the load here or here will have the same results in terms of the amount of force required to deform or break the block. But carbon isn’t like this. Carbon fiber isn’t isotropic, it’s orthotropic in other words it’s a bit like a wood. Parts made from carbon fiber can’t be one solid chunk as is the case with metals.
Another major problem is the manufacturing process. If you wish to make strong carbon fiber parts you really have only two options. Using dry carbon fiber layers and then bonding them manually together by brushing or rolling resin onto them or by using prepreg. Advanced manufacturing process than involve an autoclave which exposes the part to both high pressure and high temperatures during the curing process to ensure the best possible part uniformity and surface finish.
And as you can see this process of manual stacking of layers, long curing times and the high cost of the raw material itself explains why carbon fiber parts are so expensive. Another issue is that this type of manufacturing process can be very difficult to apply on parts with complex and intricate shapes.
But in 2010 at the Paris Motor Show Lamborghini unveiled something called the Sesto Elemento, a striking limited production run race car. It’s name means “the sixth element”, which is the atomic number of carbon and indeed the car’s chassis, body, drive shaft and suspension components are all made from carbon fiber, but it wasn’t the first to have so many parts made from carbon fiber, instead it was the first to feature something called Forged composites. A brand new unique "forged "carbon fiber manufacturing process which was employed in the tub and suspension arms of the car.
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#d4a #carbonfiber
00:00 Carbon fiber vs steel vs aluminum
10:29 "Forged" carbon fiber
16:46 I contacted Lamborghini and other pioneers - Auta a dopravní prostředky
CF cloth: amzn.to/3xjc5ai
DIY: www.easycomposites.co.uk/starter-kits
AWA: www.awacomposites.com/
Patreon: www.patreon.com/d4a
Titanium rods: czcams.com/video/PzblJe7cwCY/video.html
Motivation: czcams.com/channels/t3YSIPcvJsYbwGCDLNiIKA.html
Can you do some research on forged chrome molly 300M gun drilled/machined hollow crankshaft for high-performance cars with a modified racing engine. You should do a video on rare custom cnc machined forged 7068 aluminum alloy engine internal race parts (rods& pistons) Plus total seal gappless metal piston rings
please check more the greek manufacture his totall scam do and inside in his car chaos
Could you make a video explaining the advantages in terms of power of having different amount of cylinders for the same displacement?
You are comparing apples an oranges. You should be asking why there isn't graphene steel alloys...
IF.. you want to retain credibility when you present calculations.. do it RIGHT!.. seven point "EIGHTY FIVE".. WTF is that
Technically, Aluminium connecting rods will also last the life of the engine --- considering the consequences of a rod snap
Not even funny, not a joke either - but im laughting LOUD
LoL
Well depends on a multitude of factors. Such as WHEN it snaps. If at or near tdc in an interference engine? Possibly catastrophic. At high rpm? Same. Any other not so much. Sure there will be damage but its not the end.
@@Demonslayer20111 It will almost always snap at maximum force, which is at maximum RPM. Highest probabilities are near TDC and BDC because of the maximal acceleration at those points. Second derivative of a cosine is a negative cosine, so if one imagines TDC piston position as 1/2*displacement*cos(angle_shaft) then acceleration is negative to that and thus inward. How long elongation towards fracture takes is the question. Though if it is fatigue failure, I'd say instant snap as all the energy absorbtion in the material is no longer there.
I see what you did there......
I'm an engineer with carbon fibre experience and I absolutely agree with everything you said except for one thing. You can stack up layers of carbon fibre with different fibre orientation. This way it can sustain loads coming from different angles and making the part more isotropic. This doesn't change the final verdict though, CF parts are only economically feasible for very exotic cars.
Glad to read I had the right thought process! I was thinking the same thing while he was explaining that, "why dont they just rotate the carbon fiber sheet 90 degrees after every layer?" I figured there was some complicated mathematical or scientific explanation why they couldnt, but I guess not lol
He does mention orientation of the threads. My concern would be heat for the resin. Stuff like this gives me hope that traditional piston engines (and other engines, like wankels) will survive forever, even as they become hybridized, use waste-produced fuels or hydrogen, etc.
Iv actually been using carbon rods in my turbo bike for a year now.. it's working well at 60+psi of boost. It is chunky but seems to do fine so far. First version didn't do great but after some testing it's worked although with some less than conventional design. It doesn't have that many hrs at power so can't speak for long term.
@@oliverscorsim that's an absurd amount of boost. In a liter bike that would be like 600+ hp!
In something like a Honda Valkyrie, it could be more!
Do you have a CZcams channel or something?
@@jessev9686 iv got a few old vids on this channel but Iv been grudge racing it aswell as developing it. But hoping to break the 100hp goal with 155cc. I will say the epoxies exist for the temps and forging is how I did it along with a few directional layers. My crank is pressed together so no rod bolts to strip. I do weld the pin after pressing. And I have a bushing in the small end. Making the part wasn't all that hard once I made the mold. As far as production it has to sit in the mold under pressure for too long in my opinion but it could happen. In my case I had forged steel rod and I started bending those went to some fancy billet that works but about half way through testing (maybe 50 Dyno pulls in) they would be done (stretched). So I tried carbon. After I fixed a few things I learned in the process and found the right resin I haven't hurt one yet but I am out of turbo for now.
One thing you didnt mention about aluminum rods are they are "Shock Absorbers". That is a big reason why they are used in racing engines. They lesson the "hit" on the bearings, ect. Top fuel rods actually shrink after a run. That is how much force is being put on engine connectiong rods.
He also forgot heat. It gets hot in engines.
@@Delt4_Cr4wfishHe mentioned that it gets hot in engines. If you had watched the whole video.
@@juanc5149 i did
They're used in racing engines because racing engines are built to last like 10,000 miles lol
@@woozledog And the top fuel engines op mentioned are rebuilt after every 1/4 mile. The spark plugs, seals, valve springs, pistons, rods etc are all literally consumable parts that are done after 1-4 passes.
Composite Technician here: Very well explained. Absolutely well done.
An incredible video, thanks! Never asked for it, but definitely loved it and helped me to understand the theory behind it
love your video too
I wanna see CarbnFibr woven into an Escutoid pattern, then locked into shape via resin.
czcams.com/video/MkfmCLiJ6kI/video.html
so awsome to have the master as a companion
Gud comment. And gud vid also.
Greatness meeting greatness!
A pro stock team experimented with carbon fiber connecting rods and found out that every time the car experienced tire shake it destroyed the rods. They decided the CF rods weren't worth the expense and were too fragile when subjected to the stress encountered in an imperfect world.
Thank you
I just commented above that carbon fiber is much to rigid. Then I see your comment 👍🏼
I put a motor in a tow rig for a race team that was competing at Heartland Park Topeka and they dropped a valve. Inside the truck on the console, they had some carbon fiber rods. This was in 1996 and I asked them wth they had and where they came up with them ? They told me they were working on them and had them to where they would handle the compression but couldn't handle being pulled apart at high RPMs. They also said I would be seeing them for sale within a few years.......... haven't seen them yet
for sure I agree. the compression effect of the aluminum is needed 👍
the advantage of steel/aluminum is that they’re flexible, even if they’re forged they still have that small flex that cushions vibrations
You are a breath of fresh air, I build my own engines for Drag Racing and Road Racing. Every time I was Drag Racing at Fremont Drag Strip, when I came home I took the engine apart, at that time I was running a D/Gas 1955 chevy four door sedan, I ran a Chrysler 4 speed transmission and 1957 Pontiac Rear Axle, leaving the staring line at 10.000 RPM, I was able to lay a big gate job on my competition, 6-14 rear axle ratio, the 288 cubic inch chevy engine was screaming at the finish line. When I got home I found the Con Rod Bearings were moving a round, so I added a windage tray to the back of the pan, but when checked the Rods I had Boxed in I found the pistons were hitting the heads because the rods were Stretching even though I had right at 001. of and inch clearance. The next time I ran the Bearings looked great the windage tray worked, but the Pistons were hitting the heads too much. So I bought a new set of Carrilow, Steel Con Rods. Those Connecting Rods were So "Good", I was able to use those same Rods in other Engines I ran. Never "Broke" and Engine because of making sure I had "Good-Equipment" and that I checked the engine after hard Racing. I would like to get more information on the New "Carbon-Fiber" Rods being sold through Carrilow.
Why were you spinning a sbc to “10,000” rpm? Aint a sbc on earth making power that high especially in the old days with 23* angle heads. Also how can a piston hit the “head” “too much?” It shouldn’t hit it at all! I’m very confused here and the “ quoted” words you typed are misleading.
Have you looked into titanium ?
On that Lamborghini connecting rod sample, the bolts thread into that hunk of metal that makes up the logo. Also, you can just use nuts on the other side of connecting rod bolts, it’s not necessary to have the thread in the rod itself. Titanium rods usually are set up this way. 👌
When we see carbon fiber/carbon carbon connecting rods in Formula 1 engines, then we'll know that they have overcome the obstacles inherent with CF/CC. Until then, it is pretty cool to think about the performance advantages of such a lightweight and rigid material inside of a reciprocating engine.
Carbon fiber and epoxies and most composites in general that we have are way too brittle for engine internals. Would be pretty cool if it happens in the future though
Well said.
@@jacenharding2674true carbon fiber is very brittle also they use titanium connecting rods in F1 which are stronger than steel and stronger than aluminum and just about as strong as carbon fiber so.
Unless I got my fax wrong I don't know maybe I made a mistake.
I don't work at McLaren or something lol.
@@jacenharding2674not just brittle. The epoxy will never be able to handle the heat inside an engine.
@@NebosvodGonzalezyou got your facts wrong. Titanium is not stronger than steel. It is very slightly less stronger than steel while weighing as much as aluminum which is what makes it a good metal on a lot of applications. Steel is slightly stronger but way heavier.
"Nothing like a thick black strong rod..." - Rob Dahm.
That's what she said.
I could see Rob trying to pioneer carbon rotors.
@@deciplesteve how, he can’t even get a car to run right…
@@dannyr3346 I don't think you've watched anything he's done lately cause the 4 rotor is running, driving and doing fan fuckin tastic. Bottom line... he's far more capable than you'll ever be.
Thats a Myth needs exposing 😂…czcams.com/video/YnQSYYw3aeU/video.html
This channel has developed beautifully over several years, and keeps providing technically accurate observations and facts. Very well done, please keep up the great work that have been doing.
Congratulations!
You are awesome!
Nobody has ever so perfectly illuminated me the differences of
CF vs CC.
It was driving me nuts.
Now for my purposes I will use the correct resin along with CF.
Thank you.
Would have been interesting to see titanium rods compared as well, such as those found in the LS7
Titanium rods suffer from fatigue and catastrophically fail. Aluminum stretches like bubble gum and is micrometered for reference after runs.
I also remember reading, a long time ago, about ceramic connecting rods.
I was under the impression that titanium is the strength of MILD steel and weight of aluminum. Not actually as strong as hardened steel.
@@RadDadisRad
All metals will suffer fatigue and catastrophic failure if there isn't enough material. Titanium is used in some rods. AML V8 for example.
Aluminium doesn't stretch like bubble-gum, it has quite a low strain-to-failure. It has a finite fatigue life; no endurance limit and has a low fatigue strength/unit volume compared to steel (since mentioned in the article).
@@RadDadisRad not really, 917 had titanium rod and they still managed to make 24 hours at full throttle, heck some even had titanium crankshaft
I'm not really a car buff, or especially interested in this subject, but I found your presentation absolutely fascinating, informative and easy to understand. Additional knowledge about anything, is never a waste of time. It is a brilliant video. Thanks.
On the contrary, I'm here just for the well deserved digs at the Lamborghini corporate :-D
Aluminum rods are used in topfuel racing because aluminum does not transmit the forces to the bearing, it acts like a shock absorber. A steel rod would destroy the the bottom end in a topfuel engine.
I sure wish I had a guy like you around when I was young, a lot of headaches could have been avoided. Keep up the amazing videos brother
Aluminum rods are also used in big boost applications because of their ability to take the shock away from the crankshaft.
Only downside they have to be inspected and replaced more often than the other options
@@jaycqc8136I think the implication here is high-end racing; they'd be rebuilding the thing all the time anyway.
I heard that in top fuel dragsters the rods are replaced every half dozen runs because they become shortened.
@@mnxs They dont rebuild the engine. Not even top fuel dragsters get an engine rebuild after each race, thats a myth. They do get an engine inspection, they open it up and if the parts are good they go back in.
@@rykehuss3435top fuel cars rebuild the engine between runs and replace whatever is needed including rods...
I can not find a SINGLE issue with this video. It's not only great, it's amazing: the lack of any music helps the viewer focus on the actual matter at hand, the audio is clean and clear withour any noise or distortion, with perfect volume level.
The subject is presented seamlessly in logically connected steps and progression, everything is well thought out and presented.
Like a few commenters have already said, this level of quality and professionalism is EXTREMELY rare on CZcams, and is up to par with professional documentary and educational videos.
I was about to ask if you are a professor because you could definitely help a university student understand a subject matter.
Keep up the amazing work!
Subscribed!
I prefer no music so i can play my own in the background.
well, he didn't get in to the cost and manufacturing overhead which imo, is the prime deciding factor when choosing a material.
4340 at 1cm2 cs can not withstand 75000n. Thats the only thing.
the tiles on the Columbia were not carbon carbon, there aerogel and 98% air....thats a flaw
There are bound to be some errors in details in a lengthy video, but my comment was regarding the quality of the video and presentation itself.
It was very listenable and easy to follow.
I subscribed solely because of how in depth you went with the diagrams and information on the mechanics of the materials and such. I am not a car guy by ANY means but if your channel has more information rich videos like this, I'm in.
Way to go, Stockton Rush watched this video and now 5 people are one with the ocean.
😂
Omg you just killed me😅😅😅😅
I was a little surprised that you didn’t include titanium rods in the video. I know they are available for several AMG engines and allow considerably higher revs.
They are factory in some of the LS corvette engines.
He has an older video where he compares titanium connecting rods to steel and aluminum ones
@@bobsbillets good to know
Titanium is a great Material.
And probably the real reason why we ll not see carbon fiber rods soon.
Titanium rod weigh about the same as the claimed weight for carbon fiber rods in this video. Of course depending on the engine.
But titanium ist so strong, that you simply need less material, while with carbon fiber you need more, due to the different forces in an engine.
They're great if you can keep them from galling the crank shaft. The Honda C engine has titanium rods, so does the LS7.
But they have both had instances of galling, more so for the LS7. The surface coatings fail and that's that.
“Your car costing $8k more, that’s definitely something you’re going to notice”
Unfortunately, I think that’s a big part of the appeal for AWA’s target market.
“Well sure yours has the teakwood dash, diamond encrusted shifter, and kangaroo leather seats, but does it have the carbon fiber connecting rods?”
“Uh, what’s a connecting rod?”
“Oh you poor peasant… remind me to take him off the guest list for the Christmas party”
well to be far spenting more on a rebuild of already expensive engine like a LSX-7/C7 corvettes or 572-hemi ford-camer/vodoo ect. might be worth it vs aluminium rod's as TBO's are way longer ect.
1k to 2k per rod/piston if i had my 50K to 100K or more job on my 2-gen hemi that's on the rebuilding stand it would be tempting and im a average joe in 🇺🇸 but my luck sofar im not buying anything right now as the last 2 years in a row iv made less than 5k to 10k usd aka poverty 😑
@@richardprice5978 i hope things get better for you
@@posadist681 thank you. me two
Your car will cost greater than $8K more because it will have no connecting rods at all. It will be electric, whether you want that or not. And the electric propulsion tech is such a drawback that most consumers don't want it, but it will be forced on you because klimate krisis. And if that result means you can't really afford a car at all under those terms, then that's even better because we ultimately want personal transportation to be less accessible to the masses for the greater good of our society. You're welcome.
@@onemoremisfit as a pro-mechanic 👨🔧and millwright / out of worker aka poverty, parts i would agree with you and yes up front sofar battery packaging to go 300+ miles is $$$ without a recharge but maintenance is as much ect. so ROI is a wash or a head and daily more convenient to drive, and my 80's Chevy truck ( that's already a painful experience to get tags for as 1970-1999~ gm sucked at thing's like smog testing ect. ) im considering having it a full BEV but like i said im a broke FM so not in the cards this year as for the charger no it's staying a V8 BBM / hemi-stick car so im not sure how im being "forced to change my 60's car" but fuel costs in 2022/6+-usd ⛽ vs my income don't help to afford to drive it longer distances ect.
Your talking skills are awesome. I am not even near car mechanic and it was never my hobby, but man, u made me listen the whole video without skipping. Very unusual for me because I almost always fast forward videos.
This was fantastic, your explanations were so clear and well-delivered. I'm looking forward to more stuff like this, glad to be a new subscriber
Four things from a former aerospace composites M&P Engineer:
1 - “Forged Composites” is nothing more than compression molding, which has been done for decades in Aerospace for lower strength parts. We used ribs made from compression molded graphite in some ribs that didn’t see much load.
2 - The anisotropy of composites is not a detriment for connecting rods. The load is only in one direction: compression/tension with a little torsion and bending. Connecting rods could be made with properly aligned fibers (some along the length, some at 45 degree angles) to take any load in the engine.
3 - Epoxy would be not great for connecting rods, but BMI resin can handle the heat and oil very easily.
4 - Adding threaded inserts to composites for bearing loads has been done, and I don’t see an issue with this application.
If I were tasked with designing composite connecting rods, I would use BMI resin with Resin Transfer Molding. This would allow for making the connecting rod hollow or foam filled, with precision placed inserts or metal sleeve inserts that can post machined later.
Addition from a carpenter:
Your second point is exactly right, the anisotropic behaviour doesn't really matter since a carbon fiber part could (or probably already is) likely be made just like plywood.
If you rotate the layers, such that in a top-down view they alternate horizontal and vertical, you get rid of almost all of the shrinking/expanding wood does when reacting to humidity. Not to mention that plywood-like materials are much, much more resilient compared to solid wood of the same species and thickness due to the crossed fibers spreading the load instead of shearing apart. This would apply to a carbon fibre part as well, I'd assume.
Thx from an aircraft mechanic.
BUT connecting rods will primarily experience high compression loads. Those are not considered to be the strengths of fiber composites, as compression is mostly carried by the resin matrix.
I doubt it would handle the pressure in modern forced engines.
@@hanswurstusbrachialus5213 very much agree.
@Alfred Wedmore lol. You should know by now that the trend these days is to make stuff up by claiming to be something related to the video topic. I can make up one right now that will be more believable. "in the most fake voice you can think of": As a former engine builder for a reputable company, blah blah blah blah blah...
@@BestMods168 yes as a living lego person I personally prefer acrylonitrile-butadiene-styrene for all my engineering. It’s a great durable thermoplastic that can take all the power a human child can throw at it.
15:30 "When a small piece of foam fell off and hit the wing of the Columbia" - a small piece 60x40cm, weighing nearly a kilo, and travelling at hitting it at a relative speed of about 800km/h. Not much would have withstood that impact.
Would anything survive after something like that? lol
@@ridezosmon2306 A Toyota Hilux.
@@yapod9061 Or a ´94 Celica.
@@ridezosmon2306 an old Nokia phone
The carbon carbon failure also wasn't the source of the failure, the fact that the impact destroyed the insulating tile is what caused the catastrophic failure on reentry. To place blame on the carbon carbon, is both obscure given that there aren't that many applications of hot structure outside of shuttle, and an irresponsible recollection of history
Your videos teach more more in a couple of minutes than I have learned in years of school or even two semesters of auto class. Thank you for your service in free education.
That is by design. They make you take classes you don't need and the people teaching the classes are losers. Now then, enter the brainwashing and you have a dangerous element in our society. So to sum it up, save your money and seek your dreams and quit relying on a piece of paper to get you anywhere.
One of the best 24 minutes I've spent.
Not only are your statements technically accurate, your extremely precise selection of words, is utterly amazing.
And I get the impression that English is not your primary language, so it's even more impressive.
in those top fuel cars the aluminum connecting rod in a sense acts as a shock absorber. spreading the load time so that the crank doesn't see such a spike in load pressure probably stopping it from blowing itself apart. by spreading that impact time out a bit. they measure the life cycle of those rods by how much they have been compressed (shortened). those cars are a balancing act of many different parts made of different materials for different reasons. I bet that those rods are aluminum for more than one reason. but in this case comparing carbon fiber and aluminum as rod material this shock absorption effect of the aluminum gives a big advantage to aluminum as being the choice "I Believe".... thanks for the video 👍
Was thinking the same thing watching the video. Selecting aluminum rods isn't always about weight. Nitro and nitrous motors often go aluminum for it's malleability which absorbs some shoick loads of more violent power adders. Some big displacement drag engines will go aluminum for lower weight but this has more to do with the length of stroke and trying to reduce reciprocating mass at high rpm for reliability than reducing parasitic losses.
Also the fact that those high end race motors aren't made for more than a few miles of use.
@@frankbliss2924 Usually those engines are only spun about 1200 revolutions from start up to finish line !!
Impressive video. Awesome details while staying relatively short and concise. Deep dive on something few people would even consider a topic, but one which is quietly really interesting. That's a sub from me, looking forward to watching more👍
Incredible video! It's fun, it's informative, it's great! I love your channel! You have, hands down, the best automotive channel on CZcams! Keep up the great work!
Garage 54 (on CZcams) made carbon fiber rods. They lasted about 15 seconds! Now they are just some guys in a garage but they have done some amazing things. Like adding 2 cylinders to a 4 cylinder to make an inline 6, and it worked!
They lasted 15 seconds because thier carbon lay up process was a joke.
Off-topic for carbon fibre, but adding only two cylinders? Check out the work that Allen Millyard does in his shed: czcams.com/video/sjxiHLZdSGw/video.html
@@billedifier8584 yeah that's pretty sick! The Garage 54 guys don't do any of the stuff they do excepting it to last, it's more of experiments.
Definitely going to look through this guy's videos though! Thanks man! I'm always down for finding new interesting stuff on here...
I remember the fanfare of carbon-carbon pistons for two stroke engines (I worked in the motorcycle field for 30 years), and the unceremonious disappearance of the new "miracle material" almost as fast as its appearance. So many youtube channels get so much wrong that I was skeptical when I clicked on your video. I was wrong. Outstanding grasp of the subject matter and first rate ability to convey that knowledge. Well done, sir. Very well done.
The way you explain these things in a ELI5 way are magnificient, subscribed :)
Fun to watch this video, this is a lovely way of linking up the classes I had in university for my engineering degree to cars.
I am speechless, so I'll write instead. This is the first video I've watched on the channel, and within the first minute I clicked the Subscribe button. You have so thoroughly and logically analyzed the topic that I can't help being impressed. You are also a very good presenter. I hope to enjoy many more of your videos. Well done!
You found gold welcome
Amazing channel, you won't regret.
One of the best out there.
You're in for some comfy binge-watching brother. Go straight to his "iconic engine" series. Good stuff.
OH You will love the engine balancing series!!!
Dang... I know I am walking away, with a much greater understanding of engine internals, and the life cycle of steel, aluminum as well as carbon fibre. I can also say, I now have a greater understanding of possible use case scenarios for carbon fibre and forged carbon composites. Kudos to D4A for putting together such a clear, concise informational piece. I loved the video and I am now a new Subscriber along with all others who have clicked on the magic button... #d4a
Thanks, one of the best technical (for mugs) explanations of steel v Carbon. You covered all aspects at least for me, very well explained.
We've used carbon composites like forged carbon fiber, in the medical field for a couple decades. They are not only light and strong but also conductive and radiolucent (for XRays). Excellent video.
Just found this channel. Some of the best content I've ever seen. No fat. Clear and complete explanations.
Just don't make a submarine out of carbon fiber.
Why not
@@chud1187cuz it fuckin floats
@@chud1187last time someone did it, it imploded quite violently
It is amazing that how you present complex issues so that I can understand it. Well done. Thank you.
Great presentation! Clear, orderly, logical -- no extraneous material. Loved it.
Respect! Your explanation is on point! I've worked and researched a lot on carbon fiber composites (Formula Student, Research projects, my masters thesis, research my students did, you name it) and your short presentation here is outstanding. Very well presented!
And actually, carbon fiber composites are known not to like compressive forces. They are better in traction than compression, so basically the opposite of what a rod has to do. We've even been proved recently that CF doesn't like pressure with the little Titan submersible...
I love this video learned so much from this very technical information you just gained my subscribe 💪🏾
Great visualization. Just had to note that the quoted strength for 4340 steel alloy is for annealed alloy, which is basically never used as is. Commonly used 4340 when tempered in useful, tough condition has almost double the tensile strength, so 1cm2 rod would withstand up to 15 tons before breaking. Strongest alloys, likely maraging steels, can have tensile strengths up to 30 tons of similar size. However, this may be semantics in a bigger scheme, so take it just as a sidenote.
Which is why gun barrels are made from it, as are bolt carriers
Fantastic video! I love learning about the science, physics and material properties! Your videos are way more informative and educational than the usual car channels that only discuss the dumbed down, practical applications of tools and tech.
I agree, fantastic video. Accessible to the layman but also interesting for the more technically inclined people. Nice work, keep it up D4A!!!
@@noahvdl3331 you hit the nail on the head. I’m definitely a layman but this video answered all the questions I had on using CF for internals and even questions I never thought to ask. Definitely subscribing
GReat video demystefying Steel vs Carbon in the first place, but also steel vs Aluminium hardly understated ! Love your videos !
Impressive how you make such an interesting and complete dissertation out of an apparently simple topic. Thanks!
Wow, I love how you explain all of this stuff to all of us, so easy to understand. Thanks!
Extremely well researched and expertly presented. I learned a ton ! Thank you.
Thanks for the excellent explanation of this fascinating topic. I really enjoyed watching and listening.
@22:51 literally the best engine montage on all of CZcams 🤤🤌 This man knows motors. Respect brother. 🤘
An excellent video! Great organization, great graphics, great explanations. Well done! I learned a lot about the use and the limits of carbon fiber. Thank you.
At first I tought this was going to be a long and tedious story but NO , this is really well explained and worth watching !
You explain this brilliantly and extremely usefully: what a communicator!
Your illustrations show the materials being "tested" and rated for strength in tension, but the vast majority of the force on a connecting rod is going to be in compression both directly down through the rod and laterally off to the sides. as the crankshaft rotates. Good video, thanks for sharing it.
Great presentation. Thank you for an informative and easy to watch explanation with some good old common sense thinking. Lots of work went into this and I commend your approach and determination.
Another piece of brilliant work, D4A! Could you make a video someday about your education/background? I'm guessing you have a MS in Mechanical Enginerding with a lot of hands on practical experience. Your content is always very well explained and easy to understand. Thank you for the great educational videos.
Super presentation! very well made and informative!
A really good video, that has a lot of research behind it! Good work!
I'd love a video on advantages/disadvantages of drilled vs slotted vs drilled and slotted vs normal rotors.
I have a friend that is mech. Engineer with degree from GA Tech. Asked him this before and he said he had an assignment in college to determine this and the loss of braking surface for the holes /slots is actually worse than the brake cooling gain (and subsequent brake gain) from having drilled/slotted rotors. My thoughts (not a mech engineer and haven’t asked him this theory) is that the amount of carbon in the rotors is what matters the most…. But not sure how the carbon affects the cooling either. BUT the reduction in spinning weight might also be a factor in buying drilled and slotted rotors. A lot of dirt late models actually run scalloped rotors to save some rotating weight. I would definitely be interested in video covering all these factors though. Gotta get that advantage wherever we can!
Fascinating stuff, presented so very clearly and detailed ... especially for a casual "watcher" of automotive stuff ... like me. Really neat. Thanks d4a guy, much appreciated!
DT
Gained a sub because: tremendous explaining skills and great visual components while talking. Thx!
Great informative video, answering the type of question car buffs love to argue over. Great content
Carbon fiber sheets can be layered with 45 degrees rotation between layers, fixing the problem with different strengths directions.
The mats you show are already weaved with 90 degrees directions, so they should be good enough already.
A conrod does rotate, but the forces are mostly only in the piston direction, a conrod is always worn by the up and down motion never on side rotating forces.
The forces are mostly in the direction of piston travel only when the piston is at TDC or TBC. When the crankshaft is at 90 degrees from TDC the side forces are considerable..
@@cousinfester4621 The piston is still trying to press the conrod together or apart, even at 90 degrees on the crankshaft.
I'm glad that you covered anisotropic vs isotropic materials but I think tensile strength vs compressive strength is a VERY important distinction when talking about connecting rods. You even showed some footage of carbon getting crushed but it would be worth showing a graph of tensile vs compressive strength.
One more brilliant video. Thanks again !
Thank you for sharing this intresting information and video.
The newer materials like carbon fiber and Kevlar are amazing.
and they keep getting stronger and more resilient every year.
Absolutely love this video, Great Presentation and Narration.
yes but no. this amazing materials actually not changed their properties since their development in mid-sixties.
you Sir are a storehouse of knowledge and professionalism. Thank you for sharing this information and keep this level of information coming.
I learned more from this man than looking up the entire internet combined. Your videos are so helpful.
Very good video, very informative and im not a gear head at all and understood every term you used. Thank you Sir. Extremely professional explanations on CF rods and application.
The only Street application I can see for OEM carbon fiber engine internals is top of the line vehicles like Porsches GT RS models, or whatever Lamborghini and Ferrari are calling their top models now.
Outstanding presentation…the best I’ve seen on a highly technical subject intended for the average viewer!
I love your channel ! Keep up the good work !
This is a simple, concise and easy to understand video. Bravo.
Very well made video. Very educational and explained in a way that anyone can understand.
Awesome video! Thanks a lot! Viewing from Brazil!
You are the Anton Petrov of engineering! Your content is top notch!
Bro the way you explain things is incredible😍👍 and easy to understand
Another reason aluminum rods are used in drag racing, and other high horsepower engines, is it absorbs some of the shock loads compares to steel, so the crank and other components don't take as much impact.
Plastic internals may be more likely, and have been looked into for a long time. Polimotor had a mainly plastic engine that ran in IMSA in 1984/5
en.wikipedia.org/wiki/Plastic_automotive_engine
Ok now this is wacky, I love it!
Exactly,weight has little to för with it.
In top fuel they change the rods when they get tio short!!
Great video as always! Very informative!
Excelent presentation! I really appreciate the simplicity you bring to the challenges you show in the development processes.
Great video. I'm not that interested in cars and engines in and of themselves but I loved how you describe how the strengths and weaknesses of different materials determines their real-world application.
A very nice comparison of connecting rod materials and engine performance. I was waiting for you to address the effect of reduced inertia on the engine's ability to attain higher rpm along with it's ability to accelerate faster to this rpm-hence the drag-racing industry's intense interest in reducing the engine's reciprocating (especially) weight. As you are undoubtedly aware, inertia force increases as the cube of rpm. Therefore, even the smallest of weight reduction will allow significant increases in torque and bhp before material failure at these elevated speeds.
My special apreciation for the video description. It really worth reading.
Excellent Breakdown! 👍😎
Very interesting video! I do find it interesting though that you mainly mention CF in tension. Not giving too much thought to it, I believe the rods are subject to much higher compressive forces vs tensile (I have 0 knowledge of the internal forces that go on during the combustion cycle so the above statement could very well be wrong). CFRP are also much weaker in compression due to the epoxy matrix taking most of that load (at least that’s what I remember from my mechanics of composites class). Though, if you made a con rod from sheets of CF, you could make it quasi-isotopic depending on the layup
The highest forces on the rod and piston are at the very top of the stoke when the piston and rod are changing directions
An incredible insightful video as always! Especially for including the correspondence with AWA: their answers actually point out other problems, quite significant too. Examples, thermal expansion: imagine the engine having different compression ratio when cold vs hot; sign alternation of forces (all fibers, not only carbon, work well under tension, not so much under compression and awful under cyclic alteration)
Still, as cuncluded, the main issue with CF rods is that engines don't need them. Lighter and stronger rods allow for higher revs and pressure, however the piston fails earlier anyway.
What we haven't seen yet - or I am unaware of - braided or knitted fiber rods. High fiber/resin ration, consisntency and speed for mass production, quasi continous fiber (even closer to theoretical ultimate strength). And as a proof of concept why not making them first glass fiber, that will be more acid and heat resistant too
It has less expansion and contraction than metal, so not sure what you're talking about there... Also, a carbon fiber piston wouldn't work, for hopefully obvious reasons (like fire....), so thats not a factor. But moving on...
If laid properly, they more than handle repeated compression and tension. I work with this stuff as a prototype engineer at TechNation IT. The trick here is that one group of fibers work under tension and another set (say under engine vacuum - high RPM, closed throttle) will then take up the job in the other direction. You are assuming carbon weave has the properties of wood. They dont. How do you think we make whole cars and wheels out of it? Its in the way you lay it up, which is a closely guarded trade skill within the composites community.
As *concluded*, the racing and automotive enthusiast community strongly disagrees with you. Your 4 cylinder economy commute car doesnt need them, but that isnt the target market is it?... In the target market, it is indeed very useful. I would even venture to say the word "needed" because some of these engines, like top fuel, are held back by what the internals can handle without getting decreasing parasitic losses from simply increasing thickness of parts... Engine design isn't that simple.
"Pistons fail earlier anyway".... No... No they dont. There are specific situations where a piston would fail, like severe knock at high rpm. But the idea that pistons fail before rods, cranks, and bearings, is just flat out wrong. Have you never worked in the performance industry? One of the first things youll learn is that the rod its attached to will bend well before the piston cares, long as you have the tune and fuel choice right, and arent knocking. Ever seen the 6.4 liter Scat Pack engines? You know you can boost those to 900hp, stock, without forged internals, with E85R and a knowledgeable tuner? Ask me how I know... Youll see a lot of those cars crack pistons at just 6 or 7 PSI of boost. What's doing that is a shallow crown (which is how they have such high compression on those heads), and severe knock because the tuner wasnt familiar with the wacky stuff that Dodge PCMs do on top of your tune. Without knock, the pistons will far outlast the capability of the rods as you climb up the power scale. Eventually (think 1300hp ballparks), the rod will start flexing. Once that happens, pistons get cockeyed in the bore and snap a wrist pin, or catch the wall and crack a skirt or many other things. But the piston rarely has the first issue in those chain reactions.
We have braided / knitted fiber rods... You just saw them. Its called twill, and its one of the key components in these rods or any other CF load bearing structure. And you have to use several twill types and orientations for it to work properly.
Then.... High fiber to resin?... Maybe you have only seen forged carbon fiber (which is just chopped fiber in a poured resin). If you have ever held traditional carbon fiber in your hands... You held high fiber to resin ratios... We dont dump resin on there, nor with fiberglass, we roll it out, we dont want a ton of resin. The idea is to get just enough to impregnate it. Which can be difficult and is why pre-preg exists. If you went even lower on resin, you severely impact its strength. It gets very weak, very quickly. Same if you go in the other direction. Too much resin and now its prone to cracks and breaks too, because the load is not being transmitted to the fiber, its being sent through the resin, which by itself is brittle.
You don't need continuous fiber. Nor would you want it, thats a very poor way of making a carbon fiber part, both in production cost and time, and in strength of the finished part (not to mention issues with the resin cure times, vs part weaving times, vs resin curing stages). You'll see that crap in some FDM 3d printers. Its an industry gimmick (I work in that industry), nobody actually uses it. Maybe "that one time" for "that one part that we were prototyping", but thats it. Very specific uses, and when compared to production level itrems, its a very poor choice given the alternatives. Expensive too. The only other time youll see continuous strand is in carbon fiber pipe, or aero space (like rocket hulls, which is basically a glorified pipe).
Consistency and speed has never been a problem for mass production of carbon fiber parts.... Its labor, so it does take hours. But its never been an issue as far as meeting production, because the market size isnt that of a Honda Civic.... Small volumes, high quality, for enthusiasts, because they are the ones that actually benefit from it and are willing to pay the labor prices.
Acid and heat reistant, because fiberglass.... No dude.This is getting crazy now. Skipping right over the "fiberglass cant handle the forces, so it literally *cant* be a proof of concept" part of it... Fiberglass is no more heat or acid resistant than carbon fiber composite. Why? Because neither of those are the problem.... They use the *same* resins (with a couple exceptions like these rods, which was one of the engineering challenges). And the resins are the things that are exposed to acid and sensitive to heat. And acid? Who the hell has acid in an engine, aside from OAT coolant? Thats not even a factor.
You were onto something, at least for a second there... And that was heat. Resin gets softer with heat, so specialized resins had to be used.
@@astcomjakecw hello and thank you for taking the time. As a thank you let me answer all your concers one by one in the name of Cunningham's Law.
Significantly less. And allowing the engine block to "breath" around the rod is as bad, as allowing the rod to shrink. But true, the problem is minor. Still another engineering challenge.
Layup design is not a guarded skill, so much so there is commercially available software like Optistruct on top of publications, books and university courses. Material properties of resins and exact curing cycle on the other hand are - that is what makes the difference between a gimmick panel and a structural shell.
And I am not assuming that cfrp and wood have similar properties - it is a proven fact that they have same anisotropy. And just like there are different processes for wood there different processes for cfrp. Example, sheet layup is like plywood, forged carbon - OSB, those pipes used in 3d printers and copters - mdf. Still, no matter the material, the application and shape in general doesn't allow for decoupling of plies with regards to force application direction: fibers in contraction in one part of the cycle will be in tension otherwise, not unloaded or under less contaction. What you are saying is allowing for tension in another ply where the one in question would need to shear - totally different story.
You don't conclude in the trird paragraph of 10-paragraph essay, so why would you here? Anyway, all enthusiasts still mostly ride L4 economy engines while their project cars stay half-assembled in the garage or those sport cars they are working on are raced by team pilots. So they will definetely enjoy new tech in their Golf R. And the way the development works, on the early stages it doesn't make difference what niche part of the market it is aimed for. First prove the material and shape properties, dial to specific piston speed and cilynder pressure later. That is how glass fiber might work too, but on that later. Must have known as a prototype engineer, working with milled alu and osb (if not, must be wasting company money like whole RnD department)
So yes, for every operating condition there is a fitting piston-rod pair, in which the piston fails first, unless there is a tuner or builder mistake like the one you mention. Great description of buckling though, very poetic.
Twill, satin, tabby and others are all fabric weave types, but they differ from each other and even more so from braiding, which can be plain, diamond, double, etc too. Knitting patterns go even further off. Still, twill sheets are not the key component neither in existing rods, nor in any respectable shell, where UD plies are stacked, those come as satin with low number of welting stands. Twill is not even commonly used at all, what you mean is tabby and it is mostly decorative.
Yes, high. At least higher than off the shelf 40% by weight fiber, but hopefully even better than near 70 of patent-guarded. Because as you truthfully mentioned there must be just enough resin to fill the voids between the fibers.
Which brings us to the next statement: continous fiber production like filament winding allows for better fiber compaction and eliminates pockets filled with resin where the conventional plies meet. Applications like suspension connecting rods and bicycle frame pipes prove it in addition to rocket -hulls- frames. Which all are glorified pipes, true, just like the connecting rod itself. In general, everything is a glorified pipe unless it is a regular pipe. Just like the rod sitting between two bearing journals the frame is squeezed between an engine and payload.
Consistency and speed - or actually lack of those due to manual labor - are not only the problems of mass production, but the reason there are so little mass produced cfrp products and those existing have reject and recall rate magnitude higher than stamped metal or ejection molded plastic and several times higher than cast metal - "ask me how I know", duh
You know what else bonds to fiberglass besides resin? Glass and ceramics. You can apply ceramic coating to shield the rod from oil and potentially coolant as well as minimise heat transfer into the body of the rod without it peeling off under cyclic load. Or, you can have ceramic matrix in the first place. You can slip cast not only washroom sinks, but heavy load application parts like bearings and prosthetic bones, just with different clay composition. And do it fast, reliable and relatevely cheap. As said, ideal for proof of concept.
With that out of the way, I would really like to hear your thoughts on what you have skipped in 9th paragraph. For that is the only part, directly related to the original comment. No really, why would glass fiber not handle the forces, when even aluminium does? Because you want over 100 bar in originally overbuilt piece of ancient history?
Great video, just packed with learning.
THANK YOU SO MUCH. GREAT VIDEO AND EDUCATION. THANKS FOR SHARING!!!! I LEARNED SO MUCH.
There is also the aspect of stretching, when at high rotational speeds the traditional connecting rod stretches about 1.5% of its size,
so this must be taken into account in the clearance of the deck and if the stretching can be reduced with carbon fiber parts, the compression ratio can be better optimized.
wow that's a massive amount of stretch i could never imagine it that big
Those top fuel drag cars actually produce an insane amount of heat in that short run. They don't get more than 1 run out of most of those engines. There is so much force involved in that one run that their clutch plates weld together by the end of the run. They have to rebuild the entire engine and drive train after every run usually.
Yeah but that's one run of incredible heat then the parts are replaced anyway, yeah dont get me wrong they have tough internals, but an average car has to deal with heat cycling, cold starts, infinitely variable driving conditions and loads, poor maintenance and the rest, which is where fatigue comes into play
@@hamstirrer6882 Completely get where you are coming from, I was just pointing out there is more stress and heat involved than he speculates.
Three plugs a cylinder. Which one is going to melt ?
@@hamstirrer6882 first off then use King bearings. Great for longjevity. Whereas clevites will eventually eat up a crank, but are good for short usage.
Matching parts to applications is key.
Well done. Thank you for a logical explanation.
Any popular mechanics reader could have told you this but not nearly as elegantly, especially in the very last Era of the ICE...always appreciate all your vids, and your engineering for us dummies examinations...
I think the NSX had titanium connecting rods. You show a picture of an NSX engine when talking about steel con rods. Not criticizing, just checking. Great video, as usual. 👍
Correct. Same with the f430