No wasted time, just the opposite in fact. I (and others too I would bet) have valued every minute of your videos. I love amateur homebuilt helicopters and I have studied many of the same aircraft and plans that you mention and show. Getting your perspective on their operation and construction... priceless! I hope that you will achieve your vision of the perfect helicopter for you and as long as you are willing to continue documenting your journey as a builder I will follow your progress. Thank you . Cheers!
Reinventing the wheel is often spoken of as a negative thing, but it's the best way to know the essence of the invention. And that is valuable intellectual property that others cannot know. If we try to make something advanced without knowing the essence, it may one day collapse like a house of blocks. I find what you're doing very interesting and intriguing.
Personally, I don't understand how people can not comprehend that some things are done just for the sake of doing them, and for the satisfaction which comes along with it. It's not all about making money on every last project. As they say, it's not the destination, it's the jurney - er, jorney - umm... journey. Keep it up, there are some of us who absolutely love following along. It's fascinating watching someone re-invent the wheel!
@@NoelBarlau Thanks for that, yeah I don't understand it either. I guess they think the risk is too high for what it's worth but there are plenty of risky activities that are done just for the thrill of it. I think there is much more to gain from my chosen activity than Base jumping for example. Appreciate your support on my Jurney 😉
Hey Ben. Of course you haven't wasted your time. Nor ours for that matter. You're creating something that you really want to create, and something I can only dream of doing. Even if you fail 1000 times, and on the 1001 time you finally achieve what you wanted, you've gained valuble knowledge. Because you've found 1000 ways how NOT to do something. Anyway, love your videos. Keep doing what you're doing, and all of us here in youtubeland will be waiting patiently for the next episode. Take care man!!
Seing that Bensen,made me think of the rubber donut CVs that were on the original Lotus Elan. They allowed quite a bit of angle. Most Elan owners have upgraded to real CVs now, but you should still be able to find the originals and they would be light.
Very well done Ben, I wish I had the knowledge and mind like you, for example using mathematic to calculate certain things when needed. Much respect and keep it up
0.08 of a millimtere........................................... jesus! I have trouble dealing with millimetres!! Amazing piece of engineering investigation regarding the UJs and phasing (i didn't know that). Just a brilliant journey you are on Ben and as ever, an excellent video explaining the thought and engineering processes you are experiencing. Thanks for sharing pal.
Brother no one ever showed online so detail information and plus and minus of all stuff , its your speciality thanks again . as we almost all here like minded people,i think as you slowly developing it , its the main joy and main fun to feel , i think once you reached on finishing point and no challenges are left to solve the boredom starts to hit. of course there is a feeling of satisfaction of completing one project. i have been carefully learning your driveshaft mechanism and has a question weather having swash plate assembly on rotor blades would have been easier then this simple looking ( but indeed much complex ) movable drive shaft assembly ?? i know swash plates for two contra rotors isnt a joke either , just a thought how do you see entire assembly including engine could gimbals on its axe like liquid rocket engine does ? Brother ben great efforts so far i am more then happy to see you hovering . thanks
Lovely comment, thank you. Yes the driveshaft problem I'm finding difficult to solve but i think there is a solution and it's probably simple. Like the answer to a question is easy once you know the answer. You could be right it might have been less time consuming to tackle the complexity of double swash plates than what I'm doing. 👍 You ask about having the engine attached to the gimbal, do you mean like the heli trike ? ua-cam.com/video/17fD4V_kUbM/v-deo.htmlsi=y7cnR2c1Hv9WIz9E
@Ben-Dixey welcome brother. yeah almost same gimballed engine like the heli trike the link you shared . Will it be difficult for you on this point to moderate this way ?
@ yes it's difficult, not impossible as the helitrike proved. When you add a big weight to the tilting gimbal is has to be balanced. Balancing the weight without increasing the overall weight is the difficulty. The helitrike was heavy but it was a fantastic attempt and I think it could have hovered if they had long poles attached to the skids for learning control. I don't think that was an option for them because of the extra weight.
@Ben-Dixey understood, thanks again brother, I am too thinking about other options to connect the driveshaft to rottor assembly, let see if I come to any better idea,
Very cool! Surely the u joint setup would work the engine will just speed up and slow as needed? Maybe you could machine a bit off the flywheel so the rotor determines the engine rpm more if that makes sense
Well there is an overrun built into the drive pulley so speed variations would only apply to the acceleration phase. Decelerations would just bring the overrun into operation as far as the rotor is concerned. The driveshaft would experience the full effect though, much to think about but constant velocity joints would be my preference. Id like to remove weight from the flywheel as far as making the engine lighter, plenty of questions to answer regarding the effect of that. The increase in Engine torque spikes for example.
I hadn't considered your UJ's being out of phase, that does cause additional lead lag forces on the blades, but in all probability they a relatively minor part of the total lead lag. There is a way simpler CV joint, that can also deal with some length variation, called either a hardy disc or a guibo. It's essentially an even number of bushings, evenly spaced in what seems like a rubber donut. internally, pairs of bushings are bound together by fiber loops, usually aramid. Mercedes is a big fan of them in their rear drive stuff in the propshafts, starting from the W114 iirc. In your locale they might be more famously used in the Lotus Elan and Land Rover Discovery. They'll handle 4deg fine, and can deal with some length variation as well
Great comment, I think this could be used for the lower joint and I think it could be a good choice. Angles of the lower joint would be much less than 4 degrees if I move the engine back a bit. I don't know about the top joint, it depends how much force it takes to flex the coupling. Movement of the head needs to be relatively easy but it's worth investigating because I would love to use these joints. A smaller version than the ones used on vehicle prop shafts would be better as I'm only driving the shaft at 55lbs/ft. The toque on a Mercedes or discovery would be huge by comparison, particularly in first gear. There must be a smaller version that would most likely be easier to flex. Investigation continues. The simplest solution is going to be the best. 👍
@@Ben-Dixey Guibo's are kind of a "modern" evolution of an even simpler joint called a rag joint (no points are awarded for guessing that names origin). They can be made by cutting discs out of transport belt material. Given that you decide on dimensions, the flexibility can be tuned.
For quite a few years now I have filled periods of insomnia with thought experiments about the possibility of a low tech, low maintenance, low cost, low speed, low altitude helicopter, The machine has counter rotating blades to get rid of tail rotor complexity, it has fixed AoA blades and climb descent is controlled by varying motor speed with a 'collective' lever. Yaw can be achieved by tilting tail vanes. Forward/backward/sideways motion is instigated and varied by weightshifting the payload (airframe) with respect to the motor/gearbox/rotor assembly. Control is achieved by direct mechanical coupling from the "cyclic" to 'inch' the suspended airframe along a rack mounted to the motor/gb/rotor assy. This is in two horizontal axes. So the pilot increases motor/disc speed, the aircraft lifts to the desired height, he pushes the stick forward which moves the suspended airframe forward inducing a tilt in the rotor disc(s) and hence forward motion. Sideways motion is achieved the same way by lateral 'cyclic' movement. If he wants to point in the direction he's going he uses rudder pedals to tilt the tail vanes and swing the heading to the desired direction. I had envisioned much broader rotor blades but since finding your channel (and subsequently others) this would seem to be a no no. Control is entirely seat-of-the-pants stuff. As I said, I go over this stuff while lying in bed wishing I was asleep and haven't put anything on paper and I accept it's all fantasy not to say bullshit but finding your channel has been interesting and a little reassuring. Thanks and good luck.
@@caahacky Well the similarities to what you imagined and what I've built is pretty interesting. It works but it's not without its downsides, depends what the goals is.
Interesting - I don't think that the variation in RPM is the problem per-se; more the angular accelerations and decelerations that arise from this which will cause torsional vibration in the driveshaft that could be nasty if it ever hit resonance. Is there no way you can incorporate automotive ball/cage CV joints into the design?
The ball cage CV joints could possibly work if the boots were made to withstand the RPM, they might also overheat due to the speed but it is very low torque compared with driving a car for example. Lots of ways to solve this problem its just choosing the best one. The driveshaft resonance concern, yes possibly, something to think about.
@@Ben-Dixey I wonder if it would be possible to replace the boots with an oversized metal shroud? Only need to keep the dust out in this application, rather than being waterproof... Good luck, whatever. :)
I don't know if this will be any help but some car propshafts have 6 point rubber couplings that flex a certain amount and as 3 point are conected to one side and 3 to the other would joining 2 or 3 together with intemeadiate 6 hole plates fill the bill or evan hinge the plates to give a frictionless extention. Completely different tack and I know you are a long way down the path but I saw an early experimental Model Helicopter where the motor wat fixed directly to the rotor and swung in a cradle with the rotor so the control was a bit like a hang glider using the fuselage and pilots weight to alter the angle the motor was stabalised with some simple sliding rods
Thanks for the comment, was the machine you speak of the helitrike ? ua-cam.com/video/17fD4V_kUbM/v-deo.htmlsi=y7cnR2c1Hv9WIz9E Thanks for the coupling suggestion I'm going down this route, the only concern is how much cyclic force is needed to flex the coupling otherwise yes it will do it.
@@Ben-Dixey Hi Ben I can't remember the name of the machine but I do think it had a 3 wheel undercarriage so probably, Hopefully the rubber will give enough but only time will tell I'm looking forward to your future videoa well done 👍
It seems Ben this tilting head design you end up with quite a big contraption of a machine when you compare it to the Coaxial Little Pigeon the Chinese guy has developed.
While tilting the rotor will work on an auto-gyro due to the effects of relative wind on the disk, it will not work on a helicopter. You must use a swash-plate. Also, if you ever loose power you will not be able to auto-rotate, DEI=DIE.
What about using the rubber CV joints used in some vehicle drive shafts - such as a Land Rover Discovery 2 (STC2794K-2). In the Disco they run up to about 4000rpm. Based on your comment about 'boots exploding' - I'm guessing you've considered ordinary CV joints. You could make your own boots in the same way flexible waveguides are made. Imagine a stack of very thin stainless washers. Weld the first two together around the outside, then the 2nd to 3rd around the inside. Repeat to form a flexible convoluted tube. At the very least, by the end of it you'll be an expert TIG welder!
@@Ben-Dixey I dont know....but great little engines....so light and 55hp in the one I had an an old flexwing microlight. I do miss it.....keep up the good work.
Since the angles are small can replacing the solid shaft with the appropriate material, diameter and thickness of tubing absorb the speed pulses instead of the rubber coupling idea? Torsion tube? I'm not an engineer, obviously, but spitballing ideas are sometimes an opportunity to reevaluate ideas and solutions. As they say, "Do the Math." :D
It looks like the upper shaft is already quite small diameter. It may well provide enough of a torsion spring effect to absorb the vibration. You are only looking at a small small angular variation.
@@LesNewell Correct, it does spring a surprising amount too, yet its nowhere near a fatigue life concerning part. A small torque tube could also be incorporated as a soft drive, I know that's how power steering control works by twisting the shaft, it can only twist so far so it can't break.
Our helicopter science channel...🔥 Learning everyday, didn't know about the acceleration and deceleration of those coupling shafts. Now looking underneath them rotating in lorries will never be the same again as i try to check thst phenomenon. That blade slap sounds, tomorrow i get to push mine, waited on a sunday when there is less people around dont want attention and the nay Sayers of helicopters are invented already.
@@Ben-Dixey I saw dust, have given up man. First blade balance and tracking seems to be challenging me excessively. Then the rotor RPM got to 320 This one have given up for now.
@@Ben-Dixey the more I tell myself am done the more I feel like I need to make two changes First I hastened that test a lot. N failed to do blade tracking at some point I adjusted the low blade n my rpm got to 320...70 more. Two my pulley especially the recent one manually done is just shit and belts not wedging at all infact I checked they aren't even meshing sides of the pulley groove. These 2 items have limited me to give up until I try and check among small other issues.
@@JeffChoppah It's a long term project, have breaks, come back to it, don't give up. One day it will get there if you persist. It doesn't matter how long it takes.
I feel like there's a pile of ideas that could be pulled from this build to get this bird in the air again. Then again, it might be time for big changes to the design to make it more functional..... ua-cam.com/video/gbVudZv2ugg/v-deo.html
@@ultratorrent There is indeed and it will get back into the air but it will never be anything more than a hovering novelty toy. A new machine for a more serious attempt, I follow the ultralight helicopter channel, but time will tell if he gets it into the air. I'm yet to see a video of a furia actually flying but it comes from a great designer. Definitely ideas to take from it.
Are you hinting at a secret build? Giz a clue and have you actually put down the pen and picked up the spanners yet? I'm attempting a very spindly sub70kg... Think very early French cable braced affair with hang-glider wing loading.
Better think twice about "sharing" something like a homebuilt helicopter on the internet 'cause hundreds of "butchers " are waiting to cut the meat with their blunt knives. Expect "answers" to questions you never asked and the Nanny Society will do anything to "protect" you from haming yourself untill you're convinced that sitting in a chair in front of your PC screen is the safest way to lead your life. Other than that , cheer up , there are hundreds of enthousiasts who like your attempts but sadly .......most of them are rather silent.
@@leemnav Absolutely right, it can be very much like that and you know leemnav what it's like. I struggle sometimes with negative comments as you also know but in the bigger scheme of things the result is definitely positive. It put me in touch with you and Julian for a start. 😊
I can see your problem and surprised you can't see it yourself. The Russian twin rota helicopter has Missiles and Rockets and it works, so Logically if you mount rocket launches your's will work too Yeah lol
Boooo! My flying builds would raise an eyebrow or two, what then? Getting fat on the sofa is a very dangerous sport to some. Self-reliant risk-reward calculations may be much more risky than asking NASA for approval BUT its affordable and its "self-reliant" which is a pretty big draw for some folks.
@London-Lad Assessed ?............by who, the only person able to assess it is by the builder Ben himself, bringing in somone else wouldn't have a clue.
Thank you for sharing. You can always combine theory with practice to explain the principles of construction in depth. Very good video for everyone.
@@grayzhu Thank you, it's always very interesting to see what you're up to. Your engineering is amazing.
No wasted time, just the opposite in fact. I (and others too I would bet) have valued every minute of your videos. I love amateur homebuilt helicopters and I have studied many of the same aircraft and plans that you mention and show. Getting your perspective on their operation and construction... priceless! I hope that you will achieve your vision of the perfect helicopter for you and as long as you are willing to continue documenting your journey as a builder I will follow your progress. Thank you . Cheers!
You are indulging your hobby for all the right reasons. Thank you for posting
Reinventing the wheel is often spoken of as a negative thing, but it's the best way to know the essence of the invention.
And that is valuable intellectual property that others cannot know.
If we try to make something advanced without knowing the essence, it may one day collapse like a house of blocks.
I find what you're doing very interesting and intriguing.
I've been watching all of your videos to keep track of your progress. I hope you don't give up.
@@awaitingthetrumpetcall4529 No chance of giving up, this problem can be solved and it's probably simple when you know the right way.
@@Ben-Dixey 😀👍
Personally, I don't understand how people can not comprehend that some things are done just for the sake of doing them, and for the satisfaction which comes along with it. It's not all about making money on every last project. As they say, it's not the destination, it's the jurney - er, jorney - umm... journey. Keep it up, there are some of us who absolutely love following along. It's fascinating watching someone re-invent the wheel!
@@NoelBarlau Thanks for that, yeah I don't understand it either. I guess they think the risk is too high for what it's worth but there are plenty of risky activities that are done just for the thrill of it. I think there is much more to gain from my chosen activity than Base jumping for example. Appreciate your support on my Jurney 😉
Hey Ben. Of course you haven't wasted your time. Nor ours for that matter. You're creating something that you really want to create, and something I can only dream of doing. Even if you fail 1000 times, and on the 1001 time you finally achieve what you wanted, you've gained valuble knowledge. Because you've found 1000 ways how NOT to do something. Anyway, love your videos. Keep doing what you're doing, and all of us here in youtubeland will be waiting patiently for the next episode. Take care man!!
Well said 🙂👍
Seing that Bensen,made me think of the rubber donut CVs that were on the original Lotus Elan. They allowed quite a bit of angle. Most Elan owners have upgraded to real CVs now, but you should still be able to find the originals and they would be light.
Greatly explained as always. Interesting. Love the various joints
love all these problems and solutions :) very interesting! thank you for posting :)
@@JulianMakes 👍 just watched your foundry build video, what an epic burner and video that is, loved it.
@@Ben-Dixey thanks so much Ben!!! :)
Very well done Ben, I wish I had the knowledge and mind like you, for example using mathematic to calculate certain things when needed. Much respect and keep it up
Thanks for the compliment. 😊👍
Why do it? Why not? It's something you enjoy and we like following your adventure.
Good to see you are still moving forwards and still in one piece :-) You are always in my prayers. You need a team of guardian angels ;-)
Keep it up! This is enjoyable for some part of the masses
0.08 of a millimtere........................................... jesus! I have trouble dealing with millimetres!! Amazing piece of engineering investigation regarding the UJs and phasing (i didn't know that). Just a brilliant journey you are on Ben and as ever, an excellent video explaining the thought and engineering processes you are experiencing. Thanks for sharing pal.
Cheers Tyger, very kind comment and I'm so glad the video was of interest. I bet you got a lot of interest on your Rc giveaway. Great thing to do.
@@Ben-Dixey it's been popular yes indeed!
When you get one million subscribers you'll be doing that every video.
keep sharing. I love to watch your videos
I remember talking about CV joints and if I am not mistaken some cars have them in aluminum and probably very cheap to get used ones 😊
Brother no one ever showed online so detail information and plus and minus of all stuff , its your speciality thanks again .
as we almost all here like minded people,i think as you slowly developing it , its the main joy and main fun to feel , i think once you reached on finishing point and no challenges are left to solve the boredom starts to hit.
of course there is a feeling of satisfaction of completing one project.
i have been carefully learning your driveshaft mechanism and has a question weather having swash plate assembly on rotor blades would have been easier then this simple looking ( but indeed much complex ) movable drive shaft assembly ??
i know swash plates for two contra rotors isnt a joke either ,
just a thought how do you see entire assembly including engine could gimbals on its axe like liquid rocket engine does ?
Brother ben great efforts so far i am more then happy to see you hovering .
thanks
Lovely comment, thank you.
Yes the driveshaft problem I'm finding difficult to solve but i think there is a solution and it's probably simple. Like the answer to a question is easy once you know the answer.
You could be right it might have been less time consuming to tackle the complexity of double swash plates than what I'm doing. 👍
You ask about having the engine attached to the gimbal, do you mean like the heli trike ? ua-cam.com/video/17fD4V_kUbM/v-deo.htmlsi=y7cnR2c1Hv9WIz9E
@Ben-Dixey welcome brother. yeah almost same gimballed engine like the heli trike the link you shared .
Will it be difficult for you on this point to moderate this way ?
@ yes it's difficult, not impossible as the helitrike proved.
When you add a big weight to the tilting gimbal is has to be balanced. Balancing the weight without increasing the overall weight is the difficulty.
The helitrike was heavy but it was a fantastic attempt and I think it could have hovered if they had long poles attached to the skids for learning control.
I don't think that was an option for them because of the extra weight.
@Ben-Dixey understood, thanks again brother, I am too thinking about other options to connect the driveshaft to rottor assembly, let see if I come to any better idea,
Fly safe and keep having fun!
Well-done Ben more work❤ you really inspire me
@@OYEUAV I thought the video would answer your question on WhatsApp. 😉
@@Ben-Dixey 😃 exactly sir... I can't stop watching it
Very cool! Surely the u joint setup would work the engine will just speed up and slow as needed? Maybe you could machine a bit off the flywheel so the rotor determines the engine rpm more if that makes sense
Well there is an overrun built into the drive pulley so speed variations would only apply to the acceleration phase. Decelerations would just bring the overrun into operation as far as the rotor is concerned. The driveshaft would experience the full effect though, much to think about but constant velocity joints would be my preference. Id like to remove weight from the flywheel as far as making the engine lighter, plenty of questions to answer regarding the effect of that.
The increase in Engine torque spikes for example.
I hadn't considered your UJ's being out of phase, that does cause additional lead lag forces on the blades, but in all probability they a relatively minor part of the total lead lag. There is a way simpler CV joint, that can also deal with some length variation, called either a hardy disc or a guibo. It's essentially an even number of bushings, evenly spaced in what seems like a rubber donut. internally, pairs of bushings are bound together by fiber loops, usually aramid. Mercedes is a big fan of them in their rear drive stuff in the propshafts, starting from the W114 iirc. In your locale they might be more famously used in the Lotus Elan and Land Rover Discovery. They'll handle 4deg fine, and can deal with some length variation as well
Great comment, I think this could be used for the lower joint and I think it could be a good choice. Angles of the lower joint would be much less than 4 degrees if I move the engine back a bit.
I don't know about the top joint, it depends how much force it takes to flex the coupling. Movement of the head needs to be relatively easy but it's worth investigating because I would love to use these joints.
A smaller version than the ones used on vehicle prop shafts would be better as I'm only driving the shaft at 55lbs/ft. The toque on a Mercedes or discovery would be huge by comparison, particularly in first gear.
There must be a smaller version that would most likely be easier to flex. Investigation continues. The simplest solution is going to be the best. 👍
@@Ben-Dixey Guibo's are kind of a "modern" evolution of an even simpler joint called a rag joint (no points are awarded for guessing that names origin). They can be made by cutting discs out of transport belt material. Given that you decide on dimensions, the flexibility can be tuned.
For quite a few years now I have filled periods of insomnia with thought experiments about the possibility of a low tech, low maintenance, low cost, low speed, low altitude helicopter, The machine has counter rotating blades to get rid of tail rotor complexity, it has fixed AoA blades and climb descent is controlled by varying motor speed with a 'collective' lever. Yaw can be achieved by tilting tail vanes. Forward/backward/sideways motion is instigated and varied by weightshifting the payload (airframe) with respect to the motor/gearbox/rotor assembly. Control is achieved by direct mechanical coupling from the "cyclic" to 'inch' the suspended airframe along a rack mounted to the motor/gb/rotor assy. This is in two horizontal axes. So the pilot increases motor/disc speed, the aircraft lifts to the desired height, he pushes the stick forward which moves the suspended airframe forward inducing a tilt in the rotor disc(s) and hence forward motion. Sideways motion is achieved the same way by lateral 'cyclic' movement. If he wants to point in the direction he's going he uses rudder pedals to tilt the tail vanes and swing the heading to the desired direction. I had envisioned much broader rotor blades but since finding your channel (and subsequently others) this would seem to be a no no. Control is entirely seat-of-the-pants stuff. As I said, I go over this stuff while lying in bed wishing I was asleep and haven't put anything on paper and I accept it's all fantasy not to say bullshit but finding your channel has been interesting and a little reassuring. Thanks and good luck.
@@caahacky Well the similarities to what you imagined and what I've built is pretty interesting. It works but it's not without its downsides, depends what the goals is.
you can use a front wheel drive CV ball joint instead of a double-cardan CV joint.
Interesting - I don't think that the variation in RPM is the problem per-se; more the angular accelerations and decelerations that arise from this which will cause torsional vibration in the driveshaft that could be nasty if it ever hit resonance. Is there no way you can incorporate automotive ball/cage CV joints into the design?
The ball cage CV joints could possibly work if the boots were made to withstand the RPM, they might also overheat due to the speed but it is very low torque compared with driving a car for example. Lots of ways to solve this problem its just choosing the best one. The driveshaft resonance concern, yes possibly, something to think about.
@@Ben-Dixey I wonder if it would be possible to replace the boots with an oversized metal shroud? Only need to keep the dust out in this application, rather than being waterproof...
Good luck, whatever. :)
I don't know if this will be any help but some car propshafts have 6 point rubber couplings that flex a certain amount and as 3 point are conected to one side and 3 to the other would joining 2 or 3 together with intemeadiate 6 hole plates fill the bill or evan hinge the plates to give a frictionless extention.
Completely different tack and I know you are a long way down the path but I saw an early experimental Model Helicopter where the motor wat fixed directly to the rotor and swung in a cradle with the rotor so the control was a bit like a hang glider using the fuselage and pilots weight to alter the angle the motor was stabalised with some simple sliding rods
Thanks for the comment, was the machine you speak of the helitrike ?
ua-cam.com/video/17fD4V_kUbM/v-deo.htmlsi=y7cnR2c1Hv9WIz9E
Thanks for the coupling suggestion I'm going down this route, the only concern is how much cyclic force is needed to flex the coupling otherwise yes it will do it.
@@Ben-Dixey Hi Ben I can't remember the name of the machine but I do think it had a 3 wheel undercarriage so probably, Hopefully the rubber will give enough but only time will tell I'm looking forward to your future videoa well done 👍
It seems Ben this tilting head design you end up with quite a big contraption of a machine when you compare it to the Coaxial Little Pigeon the Chinese guy has developed.
Yes it is, it's far from the perfect solution, those Chinese coaxial's are beautifully designed.
im wondering if that shaft would have fit perfect if you put the shaft in the freezer to cool and mildly shrink it.
also what about a CV joint ? from a car?
@@Blougheed
Might be a bit HEAVY.
Great stuff Ben , when its done fly it out here mate i'll buy you a beer 😎😎🤘🤘🇹🇭🇹🇭
😆👍
Have a look at a guibo/flex disc from a bmw prop shaft. Maybe that will work for you.
You could be right 👍👍
While tilting the rotor will work on an auto-gyro due to the effects of relative wind on the disk, it will not work on a helicopter. You must use a swash-plate. Also, if you ever loose power you will not be able to auto-rotate, DEI=DIE.
What about using the rubber CV joints used in some vehicle drive shafts - such as a Land Rover Discovery 2 (STC2794K-2). In the Disco they run up to about 4000rpm.
Based on your comment about 'boots exploding' - I'm guessing you've considered ordinary CV joints. You could make your own boots in the same way flexible waveguides are made. Imagine a stack of very thin stainless washers. Weld the first two together around the outside, then the 2nd to 3rd around the inside. Repeat to form a flexible convoluted tube. At the very least, by the end of it you'll be an expert TIG welder!
Great help, will consider these options. Thank you.
I take my hat off to you Sir.....is it powered by a rotax 503...sounds like one.
It does sound like a 503, its actually a Johnson outboard but I believe there is some relationship between Johnson and Rotax engines.
@@Ben-Dixey I dont know....but great little engines....so light and 55hp in the one I had an an old flexwing microlight.
I do miss it.....keep up the good work.
Wonderful video.
Since the angles are small can replacing the solid shaft with the appropriate material, diameter and thickness of tubing absorb the speed pulses instead of the rubber coupling idea? Torsion tube? I'm not an engineer, obviously, but spitballing ideas are sometimes an opportunity to reevaluate ideas and solutions. As they say, "Do the Math." :D
It looks like the upper shaft is already quite small diameter. It may well provide enough of a torsion spring effect to absorb the vibration. You are only looking at a small small angular variation.
@@LesNewell Correct, it does spring a surprising amount too, yet its nowhere near a fatigue life concerning part. A small torque tube could also be incorporated as a soft drive, I know that's how power steering control works by twisting the shaft, it can only twist so far so it can't break.
in short, YES
👍👍👍
Our helicopter science channel...🔥 Learning everyday, didn't know about the acceleration and deceleration of those coupling shafts. Now looking underneath them rotating in lorries will never be the same again as i try to check thst phenomenon.
That blade slap sounds, tomorrow i get to push mine, waited on a sunday when there is less people around dont want attention and the nay Sayers of helicopters are invented already.
Exciting 👍 hope it goes well.
@@Ben-Dixey I saw dust, have given up man.
First blade balance and tracking seems to be challenging me excessively.
Then the rotor RPM got to 320
This one have given up for now.
@@JeffChoppah Sorry it hasn't gone to plan. At least you are trying, some people build just to look at.
@@Ben-Dixey the more I tell myself am done the more I feel like I need to make two changes
First I hastened that test a lot. N failed to do blade tracking at some point I adjusted the low blade n my rpm got to 320...70 more.
Two my pulley especially the recent one manually done is just shit and belts not wedging at all infact I checked they aren't even meshing sides of the pulley groove.
These 2 items have limited me to give up until I try and check among small other issues.
@@JeffChoppah It's a long term project, have breaks, come back to it, don't give up. One day it will get there if you persist. It doesn't matter how long it takes.
You will get there Im sure,
@@tomthompson7400 Mr Thomson, I would like to buy your coupling. 😉 thanks
I've got one serious question. What are you going to do to mitigate structural oscillation and damage in flight?
Periodic inspections, but just to make sure you are aware this flying toy won't go above a few feet. It's just for hovering.
@@Ben-Dixey oh thank god for that. Good man. I like your style. Just ensure it isn't a 'head-lopper-offer' 👍🏽
I feel like there's a pile of ideas that could be pulled from this build to get this bird in the air again. Then again, it might be time for big changes to the design to make it more functional.....
ua-cam.com/video/gbVudZv2ugg/v-deo.html
@@ultratorrent There is indeed and it will get back into the air but it will never be anything more than a hovering novelty toy. A new machine for a more serious attempt, I follow the ultralight helicopter channel, but time will tell if he gets it into the air. I'm yet to see a video of a furia actually flying but it comes from a great designer. Definitely ideas to take from it.
May be one day i will share 😀
Are you hinting at a secret build?
Giz a clue and have you actually put down the pen and picked up the spanners yet?
I'm attempting a very spindly sub70kg... Think very early French cable braced affair with hang-glider wing loading.
Better think twice about "sharing" something like a homebuilt helicopter on the internet 'cause hundreds of "butchers " are waiting to cut the meat with their blunt knives.
Expect "answers" to questions you never asked and the Nanny Society will do anything to "protect" you from haming yourself untill you're convinced that sitting in a chair in front of your PC screen is the safest way to lead your life.
Other than that , cheer up , there are hundreds of enthousiasts who like your attempts but sadly .......most of them are rather silent.
Yes you are so right
@@leemnav Absolutely right, it can be very much like that and you know leemnav what it's like. I struggle sometimes with negative comments as you also know but in the bigger scheme of things the result is definitely positive.
It put me in touch with you and Julian for a start. 😊
I can see your problem and surprised you can't see it yourself.
The Russian twin rota helicopter has Missiles and Rockets and it works, so Logically if you mount rocket launches your's will work too Yeah lol
For the love of GOD and your family, get that thing independently assessed, Stockton.
Boooo!
My flying builds would raise an eyebrow or two, what then?
Getting fat on the sofa is a very dangerous sport to some.
Self-reliant risk-reward calculations may be much more risky than asking NASA for approval BUT its affordable and its "self-reliant" which is a pretty big draw for some folks.
Yeha boooooo. It's not like he is flying it down to the titanic.
@London-Lad Assessed ?............by who, the only person able to assess it is by the builder Ben himself, bringing in somone else wouldn't have a clue.