Building a WEIRD RC Plane... Will it Fly?
Vložit
- čas přidán 29. 05. 2024
- To try everything Brilliant has to offer-free-for a full 30 days, visit brilliant.org/MichaelRechtin .
You’ll also get 20% off an annual premium subscription.
Signup for a free Onshape Account: Onshape.pro/MichaelRechtin
Patreon: / michaelrechtin
CAD For This Project:
cad.onshape.com/documents/97c...
Fuselage cut using Carbide 3D Shapeoko 5 Pro:
shop.carbide3d.com/products/s...
Foam Wings Cut Using:
www.diyrcwings.com/app/
Follow me for more updates on projects:
Instagram: michaelrechtinyt
Twitter: / rechtin_michael
Links to stuff I use (affiliate links):
Bambu Lab X1C: shrsl.com/29zix-2yn7-1cwx9
Bambu Lab P1S: shrsl.com/29zix-2yn7-1cwx9
Creality K1 Max: amzn.to/3uTuXy0
Creality CR-10S: amzn.to/3BuAiM2
Ender 3 S1 Plus: amzn.to/3xv7zW8
Elegoo Mars 3: amzn.to/3UwVvh1
Creality LD002H: amzn.to/3QXhpqJ
Creality Wash Station: amzn.to/3S1NTBi
Learn more about Formlabs and the Form 3+ here: formlabs.com/company/innovato...
This video was sponsored by Brilliant - Věda a technologie
To try everything Brilliant has to offer-free-for a full 30 days, visit brilliant.org/MichaelRechtin . You’ll also get 20% off an annual premium subscription.
I just custom made a RC jet. How do u calculate were the cg should be?
@@Aerospace_Engineering_Noob
25% back form the leading edge, if the wings are swept from the smaller outer end of the wing, go 25% back from there and then draw a line across and then that’s where CG is
Your problem is that it’s a V tail that is quite complicated rather try a normal tail @michaelrechtin
Try to build a Q200 QUICKIE for your next plane. VERY ODD BUT COOL AIRPLANE.
@@Gabebuildsthings1234or go crazy and make it neutral
Please don't give up.
Don't let go, never give up it's such a wonderful life
V tail was too small, didn't have enough authority to keep the plane straight.
doubt that's the issue since they were as large as the old wings
Actually part of the problem is rough air from the rear motor. If he made the fusalage longer and then pushed the tail further away from the blades is would help a ton. Wider tail surfaces might help a bit also but not so much longer. I think the largest issue is they are too close to the front of the propeller. Many pusher airplanes are more rear wing and canard style. But with this style it needs a bit smoother air and longer fusalage to give it a longer lever movement
Combined with the camera sticking out causing huge drag on one side, I'd say that's pretty much the cause.
V's too small for short tail length.
@@newmonengineering The tail doesn't see the rough wind of the rear motor because this plane doesn't fly backwards.
Little did he know.... the cheese color was a sign of the many holes to come. RIP, swiss cheese plane
lmao
"If there's a hole, there's a goal."
Wisest words ever said, now said by me 17:50pm 31/05/2024.
ouch
I mean it fits the swiss cheese model
I would love the video about the foam cutter.
That would be very cool..
My eyes got wide and ears perked up when I heard the words 'CNC foam cutter'
Bro just casually said "...on my CNC foam cutter" like it was nothing 😂. I'm more interested in that than the plane now.
Looks like your v-tail is a bit small for the vehicle. And with such a high wing loading, you'll probably need a faster launch speed to get going properly.
I once tried building something of similar proportions, and it definetly needed more surface area in the rear. maybe even add a third smaller fin on the bottem for more yaw stability.
I do agree! I'm not an engineer but I mess around a lot with foam thingies, v tails are weird, he definitely needs a larger surface!
The sheer amount of revisions you decided to pack into one video has earned my like. Most youtubers would split this into at least 4 parts. Mad respect.
I would suggest dual motor control channels, and start with the pusher at 50-60% of the puller... then you can play with it once it flies. I would also stay away from running too many experimental ideas in the same plane, at the same time. Use a traditional set of tail feathers... and keep the larger wing.
I would also make sure the props are big enough, they seem a little small-ish.
Why would you do that with the push puller? Sounds like a bit of rockets fallacy
The two props aren't stabilizing each other but creating the yaw that he notices. Although this won't fix it. Maybe rudder trim needed but he doesn't have a rudder. @@BeefIngot
@@shadmansudipto7287 Not sure you got what I was saying. Im talking about power.
Too heavy (should be around 300g to max. 700g, wings too small, ailerons too small, V angle too flat (should be 90 degrees) and a flight controller is not necessary. The motors should rotate in the opposite direction and the CG must be correct.
Have fun on your second attempt...
Everything said above. A flight controller is an aid it still needs a correctly weighted and balanced plane to fly or it just masks the problems.
How will you, (as a hobby guy) calculate the area required for control surface ? Any thumb rule. Pls let me know
Yea that’s a pretty good summery I recon. A couple of additional notes, the v tail looks to small for the aircraft which could be the source of some of your control issues, and I wonder if there is some funk aerodynamics fighting each other a combination of the prop at the front and the pusher at the back very close to the v tail. Also worth slimming down that fuselage a fair bit too.
@@fliteanalysis4927 Start with building plans that you modify slightly. Orientate yourself on the weight and dimensions of existing model aircraft.
Once you have enough experience, build your own models.
And light models always fly better than heavier ones.
V tail angle is a combination of the needed horizontal and vertical volumes. There are formulas to help calculate the needed volumes depending on the type of plane. Then there are formulas to help with the conversion from conventional tail to V-tail... you can end up either with 100-110deg or the other way around at 80deg...
Having 2 rotating masses at each end sure will increase drastically the inertia of the plane making the tail volumes calculation even more critical. Plus everything else already mentioned
Foam cutter vid! Yes. I have stopped my current build of one to see your latest. Cmon. Get with it. Lol
You need to build a scale air tunnel.
It's hard to imagine that the control problems in the roll axis are caused by the motor arrangement, so there has to be different explenation. Likely your plane has very high wing loading and requires a fair bit of speed to stay aloft. You are using quad props with quite low pitch so there is a lot of static thrust but no thrust at speed, thus your plane never achieves speed when it's controlable. Moreover the v-tail arrangement has adverse roll coupling which might make the problem worse.
You could try rebuilding the Do-335 and start testing from there since that model was stable enough to fly, also which you could find the reason why your model kept crashing. Even if this model wasn't a huge success, it was a huge leap in learning from experience and it was incredibly fun to watch. I really hope you bring up this project sometime in the future and I wish you a very, very good day!
Keep it up. You are on to something and closer to success than you think. Suggestions: 1/ Get it balanced for inherent flight stability first. Glide test it on a slope without props on it and without flight stabiliser on. 2/ Once it’s stable in glide, put a prop on the front and try it off the slope powered, without flight controller, then with. 3/ Once stable, add the rear prop, without, then with FC.
Can’t wait to see the project evolve.
Make sure the thrust angles are correct and the propellers are both facing the right way (the thicker leading edge facing the front of the plane), it looked like in the beginning the rear prop was on backwards which could lead to some unwanted roll. And keep trying, this is a cool project :)
Michael, I am glad that you show all of the effort, more bad than good this time, of trying to make this fly. But I think you need to get back to basics. Take a look at the Cessna Skymaster. Traditional high wing with a pusher puller configuration that might make it easier to get the CG in the sweet spot which seems to be the biggest issue here. Got the popcorn ready for the next video!
Content EXACTLY how I love it: Interesting, concise, great narrative, great filming and editing!
The problem with the Do 335 was the lateral and longitudinal control, for that reason the plane was with the tail in the crux form † , so I will make several recommendations:
1) Use the second wings, the larger wins to reduce the load of the plane.
2) Try to have the most uniform fuselaje in the plane, the step in form of the pusher motor kill all the power.
3) Make an X tail to have real control of the plane
Keep trying, is very interesting.
The pusher engine was just aft of the wing, which also changes the CG.
This is exactly what happens when you paint a model the wrong color. You should have consulted my wife, she'd have put you right 🙂
a real pleasure to find you here, a big hello from France and lots of thanks for your fight against the absurdity of certain regulations
@@sylvainponchelet4188 Thank you for the kind words. I shall continue the fight!
Amazing video!
Can you make a video about the electronics, and the detailed mehanics of building an rc plane?
Wouldnt having 2 propellers in a line mean the back propeller has to go through the turbulent air of the first?
en.wikipedia.org/wiki/Contra-rotating_propellers
Thats good for efficiency
@@nork7045 dont all of those have both propellers at the front of the plane? what im saying is having 2 propellers in front of each other with such a massive gap means that theres enough space to create turbulence, which would probably reduce efficiency, right?
@@theanomynusguy well, it probably isn't as efficient as an actual contra prop but the 2nd stage of contra props get turbulent flow too. You can only get laminar air flow with very specific conditions and geometries.
For that matter all pusher planes' props get turbulent air from the body and wings
@@nork7045 yeah good point
they also have to go through the accelerated air
As soon as i saw the first design i thought the wings were too far forward, if you took the rear motor off it would have been fine like that. The plane probably needs a bigger conventional tail, and the rear fuselage needs to taper down to the prop more. These planes were hard to balance in real life as well and had 1000s of hours put into them so dont give up!
Hey this is an awesome idea and I have some solutions to your problems.
1 build it a bit bigger
2 get steel cubes for nose weight if needed even. E-flite does this.
3 do put landing gear on it
4 possibly bigger propellers
5 try having a mode where you can fly it just as a puller or pusher to get it up in the air at a decent altitude so then you could test the dual propulsion.
6 you could have possibly plugged them in wrong (I don't imagine you did) but this would mean both are spinning in the same direction maybe creating that yaw issue. To solve this just flip the red and black wires in the back.
Good Luck!
In addition to the comments on V tail size, I would also recommend setting up the tail surface controls differently.
You have the control rods connected to the bottom of the surface. This is bad, because it places up control rods in compression (allowing them to flex and bend) when applying up elevator, which is WAY more important than down elevator. By attaching the control rods to the top of the surface you now have them in tension when adding up elevator.
There are ways to support control rods mid span to minimize flex in compression, but it may still compromise control authority.
What you are missing Michael - aeronautical design expertise! Proficiency in setting up model aeroplanes! Caution with digital flight controls with untested flying machine! And a few others!
On the hand - kudos for your manufacturing skills!
Wishing for good fortune!
Yes foam cutter video please. I think most of your subscribers wouldn't say no to that.
You have made a very good plan which crashed several times but you still made it again and again and tried to fly your plane. Crashing a plane and then rebuilding it is a part of this hobby which is a lot of fun. Your videos are very well made.
Usually having the center of lift in front of the center of mass causes the plane to be very unstable, kinda like the same reason why rockets have the fins all the way back, so there is 0 stability problems caused from the center of lift being in front of the center of mass.
Perhaps you could move the motor back and connect it with the propeller using a long axis
The foam cutter is awesome I NEED a video on it!!
A video on your foam cutter would be interesting. I made one myself recently and one of the problems was maintaining constant hotwire tension when cutting wings with large sweep or taper. I used a keycard reel to store excess wire and tension it (rolled ribbon springs apply a nearly constant force and have good extension), glass beads as endpoint "eyelets" to pass the hotwire, and a brass sliding brush to deliver current regardless of the wire's unwinding/winding against the reel.
The wire foam cutter looks great. It almost seems like its part of the CNC? Thats awesome!
If I remember correctly the original Dornier 355 had big rudder and elevators, but also the underneath rudder not only protected the rear prop but added more stability that was needed for safer flight. I don't think you have enough surface area on the rear to keep the plane stable with the added rear prop.
6:50 I don't think that that amount of control rod deflection is good for control 🤣
Tail: Add vertical stabilizer, pointed down with rudder and very robust actuation system. Replace V with larger horizontal surface with elevators. Insure proper balance! Increase torsional stiffness of all structures.
Your build setup is super impressive! I'd recommend tackling one unknown at a time, which would mean
1) Build a glider to test your wing loading, tailplane authority, etc
2) Add 1 motor to the glider, get the simple RC flight working correctly
*then*
3) Add the 2nd motor and live your Do-335 dreams
It'll be slightly slower going but I promise it'll be less frustrating! Great work, subscribed!
"I built a tail heavy plane and then acted confused when it flew poorly"
I made one a few years ago, but it had a flat horizontal stabilizer with two vertical stabilizers on each end and actually flew pretty good. It is super heavy so it would drop out of the sky if you didn’t have throttle.
Do-over is a good thing. Larger tail surfaces, move the wings back, she'll BE right, instead of YAW right.
1. The Fuselage is to long 2. Weight distribution at the ends of the fuselage leads to an inertia that can not be outweighed by the relatively small V-rudder size. 3. Vibration of this setup is adding turbulence to the V-rudder.
This could be a good opportunity to collaborate with someone who's also excited about RC exploration.
4:35 Those would be "ruddervators"
I believe part of your problem is that the fuselage is not rigid enough. The counteracting torque of the two motors is causing the fuselage to twist, so when the plane is trying to pitch up for example, it is also being yawed.
Aside from designing the fuselage with an intentional pre-twist so thats its straight under flight conditions (which would require an estimation of the twist you're getting), perhaps a wider rectangular profile spar in the fuselage will improve the torsional rigidity.
Keep on testing it mr. Cool video 😊
Awesome work and never give up.
Fun project 😊 add some more vertical stability area at the back. A sub-fin would help here. Basically turn it into a Y tail. The dornier had this to help with the issues you’re experiencing.
Never give up and never let the learning stop 😊
Good choice on the speedybee flight controller! I have a wing mini also after some failed trials with a ZOHD kopilot (unfortunately my plane flew away) But the software compatibility with these is great. OSD rocks!
Your workshop is awesome.
Maybe a 3d printed rod going thru the whole wing from end to end acting like a construction steel bar for support.
Try a bigger tail so you can have better control authority. Never give up!
i got an idea, what if u made some co2 cartridge rockets? im guessing theyre to obig and heavy for rc planes but the concept would be really good. I like the idea and maybe it would be on some bigger planes?
RC builders proverb: an airplane with center of gravity too far forward flies poorly, an airplane with center of gravity too far aft doesn't fly at all. But you know that by now ;)
In addition to the previous tips from the commenters, an airplane in this configuration is about the worst if you have little to no flying experience.
A high-wing monoplane is much more auto-stable, have a look at the Cessna 336 and 337.
Just got into 3d printing and I would love to see the foam cutter video. Tried a fully 3d printed machine and it ended badly. Back to cars and boats for me. This video got you a new subscriber. Looking forward to revision.
Make All wheel drive. Yeah that sound about right
There will be a lot of yaw effect from this prop configuration. You definitely need a large vertical stabilizer, and maybe even cg even farther forward. I’d also think about adding a small tilt to the mounting of the motors to offset prop effects. Maybe fly it manually first because you just don’t have enough time to tune ardupilot and that could be contributing to the crashes.
Definitely do not give up, Michael! Keep trying!!!
There are lots of airplanes you could use for reference for the geometry... So, please, keep trying! 😃
Stay safe there with your family! 🖖😊
The control surfaces of a v-tail are called ruddervators.
Awesome video!
I bet you could make a sweet version of the XFY-1 Pogo with your skills and tools.
Please don't give up!.. I saw another Dornier Do 335 and I noticed that both front and rear props are spinning in the same direction, maybe you should try that configuration?.
Cool video , you have a new subscriber 😂 loved the idea of a video on the cnc foam cutter 👌
The opposing spinning propellers do counteract roll but are additive in yaw. Imagine a hoverboard spinning on the spot
This. The gyroscopic effects of the props lead to this yawing effect. Similar to prop walk on boats but twice. And without a bigger, vertical rudder there is not enough yaw authority
You're both incorrect. In an aircraft like this, the P-factor (the combination of four different forces all combining to create a yawing moment) is balanced and counteracted between the two props. This is no different than a contrarotating arrangement seen on some Griffon powered warbirds which have no P-factor to speak of, they're just separated on either end of the aircraft rather than being stacked together. The problem here is that unlike a Griffon powered warbird, the two props are not designed for this and are not producing equal amounts of thrust, so the benefit from having contrarotating props eliminating P-factor is not going to be realized as apparently. One of them is in clear air spinning slower and developing ideal thrust, the other is in dirty accelerated air and isn't able to develop as much. Thus, you have a discrepancy between the two props, leading to a yawing moment. The V-tail is compounding this problem, and with a conventional tail arrangement of adequate authority, the P-factor discrepancy would be a non-issue.
@@Skinflaps_Meatslapperthere is actually a major difference with Griffon engines. On the Griffon, both propellers are attached to the "same place". Here, one is attached facing front and the other facing back. In this configuration, if you look closely to gyroscopic precession, they are actually piling up. If you look each propeller from the motor's mounting holes, they are both spinning CCW. To not have this problem, the rear motor would have needed to be mounted the other way i.e. facing front but it's not possible 😉
@@Skinflaps_Meatslapper i like how you said we were wrong then proceeded to very clearly explain why we are correct...
@@LBJHJP50 If you actually understood and followed along with anything of what I said, then you'd realize just how contradictory your statement is...but you don't, and you're getting completely separate things mixed up together in addition to not understanding the aerodynamics and physics of this in the first place. When you combine your very limited understanding along with your smug attitude, it doesn't really matter what I say after this, you're going to think you're right anyway. I have no interest in explaining what you're not understanding, you won't doing anything worthwhile with it anyway, so enjoy wallowing in that delicious Dunning-Kruger effect with your newfound buddies.
The reason they went down this design route with the Dornier Do 335 was to have the power of a twin engine plane with the frontal area of a single engine plane. So it should go faster. Which it did.
The Pfeil flys quite well in RC form. You haven’t got enough tail surface authority with the V-tail, which was even problematic in full size aircraft when it was used, and it introduces further complications to control. Also looks like way too much weight for the wing area. Otherwise it’s a really nice build. The foam cutter is fantastic! 👍🏻
I know it sounds like a silly question but were you absolutely certain that both motors had props that span the correct way/ produced thrust in the same direction and rotation. Hope this helps 👍 great vid
What a great video! It was so awesome to see a project like this. 😃
Some ideas: From what other comments have said, I reckon it may be a good idea to enlarge the V-Tail section, maybe you could also give the ailerons a larger surface area?
Also, the idea you suggested about scaling the model up is great! I would love to see a bigger model. Perhaps with landing gear?
For the CG being too far back, one easy fix would be to move the rear motor further forward and use a shaft between it and the prop, bearing are definitely required for this tho.
You designed this plane exactly how I would have. V tail looks a bit too small, but other than that I’m stumped on why this thing couldn’t get going
Size matters. I suspect the tiny V-tail and tiny propellers both were parts of the problem, among other things. Having the tractor propeller push air mostly straight at the fuselage, that also "wasn't optimized" to allow smooth even air flow, means having that tiny pusher prop operate in violently chaotic turbulence. Trying to stabilize with a tiny V-tail on top of that, well, the outcome wasn't surprising.
Putting the rear motor further forward and mounting the prop to a shaft might help. Also the puller-prop will interfere much more with the flow around the fuselage and wings than the pusher prop does, so maybe testing the plane with the puller motor only and doing proper aileron-trim would be advisable.
I know nothing about building planes but i got 2 ideas first maybe the props should be shaft driven so you can confirm both are spinning at the exact s and speed. Or maybe mix the throttle or a more aggressive blade pitch so the front motor produces slightly more thrust. In 4 wheel drive in cars a more front bias creates stability a rear bias makes the car more likely to oversteer making the car more drifty. Maybe the same applies here.
I am quite ignorant in these things, but I have seen what for me is a problem: the profile of the wings and/or their rigidity. With the first couple the plane wobbles everywhere possible. Then you tried a few solutions: bigger wings and their position. The plane immediately tends to lower its nose, then in the latest accidents the wings snapped. So I thought that the air at the ends of the wings near the ailerons was generating too much lift there, and/or the wings were too stiff. Maybe due to the position of the carbon bars
To answer why your plane handled so poorly, tandem props often need a weird fuselage shape that puts the center of pressure really far forward often times needing an even weirder shape to counteract it. You could do a lot to make it better, put a bigger vertical stabilizer or just T-tailing it, making it a twin boom like the Cessna O-2 or Adam A500, or making the fuselage roughly fish shaped like the Dornier DO 335 you mentioned (tube in the front, tall and flat in the back).
Number one big issue is the sharp leading edge of the wing. It stalls at even slightest AoA. Combined with a weak V tail and huge moment of inertia from tandem motors, it is a guaranteed failure.
Do the same design again but with a larger conventional tail!
This seems like it is definitely a CG/aero issue. As others have said, make sure to keep your control surfaces and tail large and your cg where it should be (25% behind leading edge or so) I also recommend going nose-heavy rather than tail-heavy to start. Also, for a design like this, a bungie or Hi-start launch will save you a lot of headache
I feel like I need to build a much simpler version of this with foam board to prove that it will work. There are a lot of issues with your build, the glaring thing that got me was how you seemed to thing CG wasn't that big of deal. CG was probably your biggest problem with this plane. The best way to find the proper CG would be to hold it upside down and test is that way. The design itself was good, that plane will fly, maybe need a little more experience and don't rely on the flight controller to correct major CG problems.
Maybe the tendency to roll and yaw has something to do with motors torque. Maybe it's the aerodynamic influence of the camera. Test it with one motor at a time until you get a stable flight, then test it with both together to see if anything changes.
The wings are possibly not stiff enough in tortion so that the ailerons can cause an opposite twist. Cover them with something like brown paper or fibreglass.
I don’t really like V-tail layout. Try a conventional one, it should give much better stability. Or just add a ventral fin to make a Y-tail. I had similar problem with one of my early planes. Does it have wings of EPP?
In terms of reinforcement and making smoother skin - try to cover it with fiberglass using elastic epoxy resin - I had recently discovered and tested this brilliant technique.
P.S. could you upload CAD model for us to edit?
Please don't give up.
May I ask a stupid question : does your motors have different spin direction?
To be elevons or tailerons the tail surfaces would have to induce roll. The surfaces on a v-tail only do yaw and pitch, which makes them ruddervators.
Pedantics out of the way, this is a pretty awesome build dude!
The back motor needs too be in the middle with a carbon fiber shaft to the tail. Try try again.
Great video!
10/10 want a video on the 4 axis hot wire 8oB .....with frickin' LA-sers! Wouldn't mind one on the CNC router either!
i alway love how you are able to make these things
Ahhh just for your info , I made one like 4 yrs ago , just that it was like a cessna , top mounted wing and one prop was on front of wing and one on the back of wing I balanced the thrust angle and it worked in 1st go 🤘
Just want to say that the concept will definately work without any problem .
I built something similar and had issues with insufficient tail surface to control it very well. Some planes just don't scale down very well and need bigger tail surfaces. So I changed my design to a Cessna Skymaster with front and rear props. With the tail behind the thrust, it flew really well and fast. I suggest changing it to a Cessna Skymaster or adding a tail boom. I did not use a flight controller on mine cause I only flew it in line of sight. Personally, I would not give up and keep trying. Flight controllers can only do so much. Personally, it is still too tail-heavy. Always fly without a flight controller to make sure the design can actually fly. Then add a flight controller to it. Use foam for the tail to keep it light. 3D-printed parts on the tail are just too heavy. Don't be afraid to add additional weight to get the CG perfect. That narrow wing cord is very sensitive to pitch inputs. Contact the guy from the channel "Think Flight" or RCtestflight for help. Those two guys helped me so much when I had questions about my build.
I reckon the problem is poor yaw stability.
When the plane starts to yaw this causes unwanted induced roll. Additionally when the flight controller tires to correct the yaw you lose some of your pitch authority due to the use of a V-tail. Making the tail bigger or not using a V-tail would probably help.
Hi. Very nice video!
Check the directions of the gyro.
I once glued a gyro on a plan in the opposite direction, and the fixing was extremely wrong. It's handled like a negative stability, even when the CG was perfect.
Epic build & perseverance! Maybe some larger control surfaces/more throw would help, and larger tail as well. A video on the 4 axis foam cutter would be awesome!
@Michael Rechtin
its the v-tail. it lowers pitch and roll and yaw stability because its angled. the fact its angled makes it so when you yaw you roll and thats why it spins when you try to yaw it. the ardupilot tries to counteract that and it does but that means you have less roll authority. this creates a feedback loop that spins the plane. another part of the feedback look is that its very lowly angled which means you have almost all rudder control going into roll and barley any yaw stability. just use a standard tail instead.
Glide test before power testing. I learned this lesson the hardway.
Idk if anyone has mentioned it already. But I'd love to see if smoothing the surfaces of the wings could help a bit as well. Filling the little gaps and having a smooth surface could prevent an early stall
Don't give up!
That canopy design is really cool. Maybe print it out of asa to avoid the heat issues for the next one
it's nice to see this design of a plane
Try a little laminate on your foam parts, it doesn't add that much weight and makes the foam real strong. Twisted Hobby, minimum rc and aloft hobbies are good sources for iron on clear laminate. It comes in thicknesses of 1 micron to 6 mm thick. I build a lot of foam airplanes for indoor and outdoor use , I have found that the laminate works very well.
Wonderful video as always 🥰😍 do you mind me asking what type of glue you were using in the build ?
Calculate the weight and adjust where you put the wings when you design the fuselage. Moving the wing backwards instead of adding weight.
Also are you sure not one of the propellers just act as a break. If they rotate at the same speed it may not actually help. They are not close to each other so I doubt you get the benefits that usually counter rotating propellers give.
It also looks like it’s too heavy, not just unbalanced.
Further are your motors angled as they should, I suspect the rear engine is just making things worse if you have mounted them straight. You might need to double angle of thrust compared to how it’s normally setup.
Depends on the engine rotation whether you should angle front motor left or right. Normally a one should also angle them a bit downward.
However with a rear engine messing with all this I can’t say for sure how you need to set it up.
Begin with disabling the rear engine and make engine mounts for the front motor angled as appropriate. When you get it to fly with just the front motor running start experimenting with the rear motor.
PLA is heavy. Don’t print parts that use any unnecessary material. If you can get away with one wall don’t print more. If you can design a model you can print in vase mode. Do vase mode.
I have not yet tested lw-pla but I have a few rolls waiting for some prints.
I suspect that it's a size issue. The plane is at too small of a scale and the air doesn't flow from back to front the right way to interact with both propellers correctly and thus it's causing instability and lift problems. I would double the size and try again and see if it flies any better.
Probably a good thing there were no by standers haha. They may need hardhats.
I am interested in seeing more of your process for cutting the pink foam with cnc.
What app did you use for the plane to see the inside and look it in 3D?