graphs and or tables with results would be super helpful in future videos when doing comparative tests like this so we don't have to remember the numbers you are rattling off in the test. thanks for this series.

You can't fool me commander. You are indeed the smartest guy on KZfaq. I've never seen higher quality garage engineering - nay - *engineering of any kind* on this medium. And as an engineer myself, a quite lowly one compared to you, I understand how trial-and-error is a critical piece of the puzzle of progress. There is no need for apologies, even in your natural Marvin Martian accent. I still can't, for the life of me, figure out what your profession was, originally, when you had a day job. Perhaps high-energy lasers - is the best bet. But you are a gem, and have brought esoteric and difficult subjects to light for me without the aid of a white board (blackboard?) - just with verbiage. Which I have learned in my life, can only be done by the best and brightest among us. The only guy who lectured better than you, in my experience, is Richard Feynmann...and then, only slightly. Though I was always partial to his NYC accent, and you're influenced by the midwest. Thanks again for illuminating us with your fantastic work.

Thank you for immersing me into your world. I was fascinated with your series on the dml speakers and the trials and tribulations to perfect them, and am currently into my third generation of builds. Your mechanical engineering, physics, chemistry, thermodynamics, etc approach to different technologies just makes me want to pack my bags and come knock at your door. Spending my entire adult life in the engineering and sciences world of repairing, building, redesigning, inventing anything and everything, without intimidation or fear of failure, built my inner core as it is today. Thank you for sharing yours...

Great video series so far. I really appreciate the work you are doing making these videos !!

Thanks for the series. I learned a great deal and the series caused all kinds of lightbulbs to pop off in my head

Only wanna say thanks to you and your great team. You comes really close to perfect and I really don't know what to do better. 😊

You’ve definitely earned my SUB. Thank you for focusing on concise science and engineering and not plastering your videos with the typical KZfaqr shenanigans.

I like your open source thinking! Thanks for all the great and detailed videos! That makes also a big difference. Have a nice evening.

Great series, really enjoyed it. Thanks for putting it together

Just found the Great videos and subscribed. Many to watch. Thanks for the great content. Keep them coming.

As I embark on my largest project too date where I've really had to fire up those Neurons, overhaul and retrain. Basically learning how to learn again . I've always kept my knowledge sponge consistently moist though it's time to completely submerge it and soak up as much as I can. Your style of teaching, methods of operation and general above average production quality have made |"Tech Ingredients" my go to source for knowledge, training &answers to any questions I've had so far. Your experiments seem to be absolutely non biased giving me answers that don't just tell me or show me a simple one directional path to my question, but a multitude of answers with all the good , bad and indifference allowing me to make an educated decision on what will work best for my project. The most important part of that equation is the fact that I was educated and it was more than enough for these decisions to be made with the upmost confidence in myself which so invaluable that I could never thank you enough for the incredible job you all do to make this road safe, manageable and so clear to the point(s) my journey is topped with excitement, promise and foremost, The ability to " excuse the pun" launch this project and get it off the ground the way I want to see it happen instead of following crap advise based on ones opinion with little of no data to examine, ponder, create and know I've the proper instruction in all those facilities and if it doesnt work its something I did wrong or simply A decision I have made poorly not wasting my time trusting someone who care for more about "cool than "accuracy" . There is place for cool in science and you and your tam have definitely nailed the recipe here acing every nuance of laughter, practicum and the desire to to step outside the box of comfortability and take o something totally new and knowing with every lesson you will kickass with a solid understanding of whatever it is you are completing next. Keep rocking and tthank you again for dunking my brain in that big cauldron of knowledge soup... needed super helping of that and you guys spoon up the best in town. Rock on. Kaj

I like your hands-on approach to testing and applied science. You have validated my belief that the Era of the individual inventor is experiencing a Renaissance.

I've learned a lot from your videos, and furthermore, your work is an inspiration. Keep it up.

This is the bees knees... inspirational vectored research, new possibilities for an uncertain future. That needs each of us to participate in creating solutions to problems as we find them. Recognise the revolution will certainly not be televised, it will already have moved on to better things! Problems will almost certainly contain the components of their own solution. Start now! Always thanks to the maestro for proceeding...

What a marvelous combination of theoretical science, practical fabrication techniques and sophisticated instrumentation and analysis. The breadth and depth of topics covered is amazing, from physics to optics to mechanics to electronics to chemistry. I can't stop watching. You are truly inspirational!

The last minute says it all. Lots of people make simple entertainment videos and get tons of views but they don't enlighten the viewer. Others like Collin Furze takes a comedy approach and never explain the hard issues in any detail. Still others think a glue gun is the solution to all assembly. Thanks for putting put proper engineering going into the details and taking the effort to explain. What I knew already it reinforced. What I didn't I leave more enlightened. I should really aspire to reach this level.

I just found this channel and I have to say, this is some great content!

nice work! very informative. clear and comprehensive testing, thanks for sharing!

As usual very informative and thanks for the hard work that you have made look easy. Very good.

4.5 years still great ideas I found out usefull for me. I watched the whole series owning the whole fleet of dji drones since phantom 4 had appeared. I like these selfbuild ones really or better your step by step explanation cause it can be applied to all the other stuff in RC hobby espesically planes. Thanks a lot for sharing all these details like balancing a prop and so on. I am really happy. Joined the channel back then when you did these speaker works or even a bit earlier I guess, but did not went back to the roots of your channel which I did today.

You definitely earned my subscription. I can't wait to see what's next

Awesome channel.. really digging the push of the unknown into the known!

You are definately pushing the state of the art. I love watching your videos, maybe because i allways wanted to have my teachers to be more like you, in my schooltime. This special kind of person, you just can't ignore and which you just have to listen to. Sadly, there are only a very few of your kind...

Nice to see someone gathering practical data. Yes larger diameter props give better efficiency but have a lower air speed. Thrust is reduced when your prop is in motion relative to the airflow (unlike a static test). If your intention is to have an aircraft that is practical outdoors where you want to move at any speed or have to deal with any wind, then you will have to decide on a minimum airspeed through the prop that will allow you to maintain adequate control in all conditions. I built a large drone for the purpose of filming kitesurfing in 20-30knot winds using a gimbaled DSLR (~5kg Payload). I achieved approx 30min flight time (wind speed dependant). Keep up the videos :)

Good vid. Inserted graph with rotor vs thrust vs power would be nice.

Yay! not putting marshmallows in liquid nitrogen. I subscribed and I am glad I did! Excellent practical science in application.

Nice work, you always do nice work. Just in case anyone was wondering. The "Rolling" shutter on the camera explains why the blades appear to bend in video playback. On a "Global" shutter type of camera it would look as it would had we been standing there.

I push your channel when and wherever I can. I recommend it to everyone I meet and really hope to see you achieve the numbers that it deserves. Your approach to science in the way you teach and share is just inspiring and I will hopefully get a workspace of my own to join you In the quest of pushing the limits of technology.

Your videos are awesome and the subject matter is really fascinating.

I am truly surprised of many Americans and their openness and care for other people of the whole world. You guys are doing a priceless job! I wish this channel to work forever. So concentrated, pure and true explanations over wide variety of really important topics. The only thing I fear is that all the videos are under YT control and no one can be absolutely sure that the private company will not limit/ban or remove the contents or users based on unknown reasons. Therefore I sometimes tend to download the exceptionally important videos from YT to be sure I will have them always in standalone mode as a backup. Also somehow comes into mind the case of physicist Stanley Mayer (“The Tragedy of Stan Meyer”). It is the best thing to do that is being done - to share information and knowledge to the world straightly online, so no organization or government can do anything to stop the truth reaching people around the world and for free.

I like how you showed the fire extinguisher in the background. Safety first. I want to see more of these high quality videos. Thanks.

Great Series! Gets me to thinking about making these foam core props for homebuilt aircraft. Great job on the development and presentation of your ideas. One last idea: The GPU converter, sounds like we are getting to a diesel-electric setup. They are getting huge amounts of power out of small diesels. Even normally aspirated, and they are very light. Diesel fuel is slightly less energy-dense, but it still way less heavy than the equivalent batteries. There have been experiments using a stock electric motor to power a Cessna 172 that has lots of power and is much lighter than the standard recip. engine. Just thinking out loud. Thanks!

Excellent content and extremely well presented. Thank you very much. I was searching for techniques to build panels out of composite materials without an interest on drones. Having only just stumbled upon your channel and watched four episodes I am now subscribed and look forward to gaining new knowledge through your various techniques. Cheers from OZ

Nice, would have been great to have a summary chart of the rotors after testing.

Great video series so far!,double Thanks

Great video, again!

sir,your channel is the best channel on youtube

Thank you very much. Fascinating stuff.

Awesome! Keep going.

Thank god AVE sent me here!!! Great channel guys.

thank you very much for sharing. watched them all.

Today I came to this channel and liked so much, thanks a lot

Great series

Hey Prof, 5 minutes in and you have earned my subscription.

Really interesting! Please keep up the the great content!!! 👍

I would love to see graphs for the differing propellers. Your work here is interesting, informative and entertaining. Even if I never build a rotor your work with carbon fiber/epoxy methods will influence me in the future projects. Thanks for your hard work. Of a personal nature, I would also like to know a little about your background and training.

I am trying to desing my own personal drone to make real my dream of flying in my own aircraft... Your work is very valuable !!!

love the cintent and channel!!! more please!

Amazing engineering, doing all the stuff I think about but never realize.

What a great channel! Liked and subscribed

Can't wait to see more on the APU concept.

Loved your content sir... Keep up and do more...

Love that you finally say that a gas turbine generator is the ultimate champion for endurance. And gas turbine ultimately fit for a single-rotor helicopter setup, not a multi-rotor system.

Wow you just touched on it, keep going

Greetings! Great video, it gives me the confidence to make my own props. It would be awesome to see you build a drone for manned flight. I know there are a few that have but you could use some of your alien technology and build the ultimate copter! Just imagine the subscribers you'd have! Live long and prosper!

Great info I subscribed!

I like your attitude, keep up good progress.

The whole time of the build I was thinking about paramotoring. The technology that you mentioned at the end would be very welcomed there too. Plenty of great channels built around that sport too with money behind them. Tucker Gott for example, but AviatorShow probably more commercialized, or you can directly contact paramotor manufacturers, I think they would be very interested as well. I saw Alishanmao try electric paramotor on his channel a few months ago and his problem was the short flight times because of the batteries. This could solve that problem.

You're right, I do like your approach.

great test thanks. do you have a comparison chart of your results. I would like to study the subtle differences.

So much fun very cool.

Thanks for the great video

Wow...great stuff. subscribed!

Great video.. thanks for sharing!!

You touched on a point that I have been thinking about for a while: using an APU (from a commercial airliner) to power the electric motors for an ultralight or a large drone to carry two people. Then, only a backup battery in an emergency and to fire the APU.

I REALLY LIKE & RESPECT UR UNIQE IDEAS...🙏🙏🙏

For those of you watching please read my comment!! How can I help?? What you’re doing is fantastic & please don’t stop!! I think you’re amazing & to take time to share your wealth of knowledge with others is priceless!! This is how our great country became what it is today! It’s my opinion that the art of transferring that wealth of knowledge is currently getting lost. I’m talking about the masses Who are only motivated by how much money they can put in their pocket. They have no interest in contributing to to others or knowing that we can do better as a society by creating ensuring that knowledge as you are. It’s very exciting to me to watch individuals like yourself who are true inventors or creators I should say! what you are doing today open huge dividends in the future of engineering science and technology. you look at things from the same perspective I was taught which there is nothing perfect in this world and we can always do better or create something that will improve our quality of life. I admire what you’re currently doing! You remind me of my mentor, my grandfather!! He worked for Boeing then GE as One of the top designer, developer and engineering. He transferred as much of that knowledge as possible. I followed in his footsteps but I do it for myself!! again what you’re doing is very admirable] by transferring your wealth of knowledge to educate and help others & you sacrifice your most valuable asset which is “TIME” to educate others!! THANK YOU 🙏 !!!!! .

I never expected that you would be so close to the T-Motor prop. Well done 👍

Just Blown away by your Video. I love prop tech. I want quieter props for my Inspire1. CF props are quieter but some say they cause t vibration from stiffness.

An hour and 40 minutes later and I still have no intent on building or buying a propeller, but I learnt something and enjoyed watching.

Thanks for the great cf laminating techniques! I build rc sailboats, and will use this on keel fins and rudders. I'm trying to work out a design where the leading edge of keel fin matches leading tip of keel bulb. With standard fin-bulb keels, the fin is centered on bulb. Problem with that is seaweed (pond weed) hits fin, then gets stuck on bulb. Once enough builds up boat is impossible to control and is dead in water. If fin meets tip of bulb weed can slide off.. I'm working out how to get lateral performance and reduce twist of fin when boat is heeled, since center line of fin will be in front of center of mass of keel bulb. This carbon fiber method should help, thanks!

Hi Mate, im building a car size 4 motor drone in my back yard. we are developing the props now, you look like you are way ahead of us.

Great channel.

Compact linear engine generators seem to be a popular choice for auxiliary power.

Damn, must be some big drones!😳

Im studying eng phys at a University in Canada called Carleton University and really enjoy your channel :) Keep it up!!

great video, well thought out and filmed, like all your channel offerings. My main interest here is with the very low rpm thrust readings for a duration time-lapse specialist drone. It's always very useful to see a big prop actually tested like this. I am a bit confused as to why the current, voltage and power at the top left insert of the frame - are going in such bug jumps and lag the thrust? It's impossible to really tell what the steady rpm figure is, for example at 1500g thrust do we take that figure as accurate, representative and a stable reading? Or assume it's as ball park as all the other values...therefore it's not going to be possible to do more than make a guess as to how your 'twist-less' 'square tip' foam core blades are performing in comparison? Why would I spend so much trouble making constant pitch wooden and laminated props over my life using the design approach adopted in every commercial and full-size/man powered flight project etc...which include this extra aspect of prop manufacture? A balsa or foam core carbon skin prop blade can be as little as 18g per blade for a 22 inch. Another good reason to make your own blades is that they can be made much lighter if they are only going to be used to generate much lower amounts of thrust, with less rpm and therefore not needing to have a big structural safety margin. I have several all balsa 20 inch one piece with hub blades that will take 150w without self destructing and weigh about 10g. I was hoping to compare the 15g/watt at 1800g thrust I get using a 18 inch balsa prop, gearbox and tiny Hextronic motor, with your results. I am also not seeking perfection in my experimental technique, I was only interested in maximum thrust and used a simple tilt arm without an accurate electronic scale and omitted to keep a record of the lower rpm, power input and thrust levels!

Thank you for all the work you have put in your videos and for sharing them. They are clearly some of the best I've seen so far, whichever topic you take on. In relation to propeller blanks: have you given any thought on 3D printing a mold for them? Even if you had to print it in different parts, it should make for an excellent mold for high expansion polyurethane foam. Advantages are, once you find the very best CAD model, scaling would be easy. Your could also pour a new propeller on the fly. Thanks again!

Great video once again. Question on the DIY props though...how well do they perform at high-load levels typical of such setups? The bigger props are normally rated for over 10kg thrust per rotor, are the DIY models capable of similar loads?

You have demonstrated and explained many questions I have on a variety of topics but when you mentioned switching from electric to gas-powered which makes a lot of sense it would seem more practical to transition to a gas-powered engine for your rotors. I suppose that it may be difficult to control using the controllers that are available compared to electric motor controllers but a centrally powered, larger rotor with three or four smaller electric rotors to control the angle would seem plausible along with flaps or other foils. With a much smaller battery backup it might be possible to create a controlled landing in the event of an engine failure provided the load was not too heavy and there seem to be parachute systems that could be deployed under those circumstances. Just as drones have eliminated some of the design challenges imposed by human pilots on military aircraft, and the monumental challenges involved with placing an astronaut on the moon computer-controlled drones could solve many of the challenges that you mentioned at the start of this series. While I appreciate the opportunities to use nuclear power to produce electricity as a cleaner alternative to fossil fuels and the opportunity to utilize off-peak power I prefer solutions like your swamp cooler, and desiccant based refrigeration systems that take advantage of simpler mechanics/reactions for the heavy lifting while taking advantage of electric power to demonstrate concepts. Small electric kickboards can now match urban traffic speeds mostly because of how inefficient moving large vehicles that displace huge amounts of air that create traffic jams is and the stop and go nature of urban congestion. Hybrid cars will be more efficient under these circumstances but they don't address the basic problem that the weight of the engine and vehicle often dwarf the weight of the passenger and cargo. I would love to see some videos of your catamaran and drone in action especially if you get your hydrofoil working on the catamaran. I have really enjoyed the past few days living vicariously through your creations.

That was great

Really liked the video, could you also do a similar test for vibration using the accelerometer in the phone, also do look at KDE direct propellers, they seem to have a better design philosophy

So cool.

I would like to see an apaeutus using that scale.. to measure thrust . Thanks for the thought.

I consider myself quite technical how am I only discovering you now? your content is incredible please don't stop please don't give up please don't get disillusioned

Ur a great engineer, but also, as equal and perhaps more important, an excellent guide and teacher...I know when someone is able to teach with such mastery, they know their craft, well...I thank you...new scriber! Best channel on KZfaq according to my interests...Is there a way to reach out to you other than by way of comment?

Nice work sir, Kudos on all your videos… Am I correct in the conversion for thrust, to be in the 5LB range? THX, Brian

Awesome video. The most important parameter is not the amount of thrust but thrust per watt. If you put that also on the screen for every propeller that will be awesome gram/watt.

Great series, Ive never never considered making my own props, but then again my GF already complains my stretched DJI 550 hex is to big. Will you be using a Halbach generator in your hybrid system to reduce the overall weight?

Thank you.

Awesome job ! I will be checking this chanel in the future too.

Hello sir thank for this video It's very useful video for me

Ooh, this makes me want to build a wind tunnel for small scale aerodynamics tests. But, I suppose you could do the same thing with a tank of flowing water.

I know this is a old video but i still come back here if there's something i missed or need!

Great series. Have you checked out the Blue Edge noise canceling rotor blades design? The geometry looks very interesting.

Your motar is very powerful

Great work , put a scale on the thing so you can get thrust numbers

I am sold!!! Great content you have on this channel. I have watched several of your videos in the last couple of days and I am pleasantly surprised to discover the talents you have so articulate introduce to your viewers. Hats off to you and keep up the good work! Where are you located? Regards

Investigate Juan de la Cierva, the Spanish inventor in 1921 of the Autogiro, now called the Gyroplane. His out of the box thinking and his mathematical genius lead him to develop methods to counter asymmetric lift and stresses associated with rotorcraft. Fascinating

You should have a lot more viewers, skills you teach on this channel are amazing. Please don't stop, and think about patreon?