Official Freewing MiG-29 Fulcrum Twin 80mm Thread

[RCjetdude]

Then, for sure, it won't balance if you put one of those in the front tray. The 6000 that I have weigh over 800g. That's quite heavy. I use 750g batteries in mine in the middle and rear tray and even then, it just balances 10mm aft of the marks. People have said that the CG at the marks is too nose heavy, but I've flown mine at that point and it's manageable. If you can't balance it with those batteries at least at the marks, you'd best try to relocate the blue box so the middle battery can sit there.

I agree with xviper on the 6000's. If I fly mine with my Admiral 6000 Pro's the forward battery is definitely on the middle tray to attain factory CG and I have not relocated the blue box.

[bandetx]

Well, that's nice to hear. I thought about how it would work in the air, but my reason was for the long rollout after touch down because adding brakes adds weight, electronics, extra wiring, proper fitment, extra cash and hopefully not a point of failure. I don't know of any models that come with brakes. The ESC is an easy way to create a brief reverse thruster. It might become a worthy practice...

Here's the catch:

Running the EDF in reverse draws tons more amps. In order to do it, I had to limit throttle to like 60% in reverse setting and add a 5 second throttle curve to prevent the ESC from automatically shutting off when over amped.

I never tried it in the air, I imagine the increased speed over the fan spinning it would increase the amp draw by even more.

[RCjetdude]

Banana Hobby sold a number of years ago an HSD 105mm J-10 that came stock with a reversing ESC. Rich Baker, the RC Informer did a series of build and flight videos on it. The thrust reversing basically seemed effective enough to slow it down on landing.

[HK111]

This is your MiG's tail, and it is not what it should be

Hello there,

I bought some spare parts. This video shows what they call a structural part.

Nice flex! As you can see, the mount for the elevator axis lies in a U-shaped plastic piece. The piece is made of very thin and weak plastic, the wall thickness is maybe 1mm. In the section with the axis mount, it contains no structural reinforcements such as ribs. It can be easily bent with a little pressure of the hand. An axis put into it can easily be deflected by 10+ degrees, in particularly down. It is resisting an upward angle of the axis a bit better than an downward angle.

Yeah, in the full aircraft, the piece is filled with foam. But only a little bit of deformation of the piece already results in much changed position of the elevator axis and the elevator itself.

In my opinion, this piece needs to be replaced or seriously strenghtened. Time for an upgrade, MotionRC!

Cheers,
Henrik

[bandetx]

Hobbywing Flyfun esc series has thrust reversing feature. https://www.hobbywingdirect.com/coll.../flyfun-series

How it works is there is a 2nd ESC servo lead that you connect to a channel in your TX, and you assign it to a switch. When you flip the switch, it reverses motor direction.

[xviper]

This is your MiG's tail, and it is not what it should be

Hello there,

I bought some spare parts. This video shows what they call a structural part.

Nice flex! As you can see, the mount for the elevator axis lies in a U-shaped plastic piece. The piece is made of very thin and weak plastic, the wall thickness is maybe 1mm. In the section with the axis mount, it contains no structural reinforcements such as ribs. It can be easily bent with a little pressure of the hand. An axis put into it can easily be deflected by 10+ degrees, in particularly down. It is resisting an upward angle of the axis a bit better than an downward angle.

Yeah, in the full aircraft, the piece is filled with foam. But only a little bit of deformation of the piece already results in much changed position of the elevator axis and the elevator itself.

In my opinion, this piece needs to be replaced or seriously strenghtened. Time for an upgrade, MotionRC!

Cheers,
Henrik

Before any conclusions can be drawn from your demonstration, I think you should do the same deflection of that part when it's on the plane. It's not a fair test to take that piece all by its lonesome and twist away at it. I've seen a few pieces in real life where it'll warp like wet timber but fill it with something and glue it in place and nothing's going to move. Besides, in this case, you might want it to bend a little bit. Like they say about a tree - better to bend than to break.
But if we're going to go screaming through the streets, "The sky is falling", how about we demand Motion make retracts that can take a good smack? Or do we have to reinforce them like so many have done with nose retract struts and even main retracts by epoxy-ing support braces in the foam (eg. Freewing F-14)? But you know what? I think I can handle it before the price of the plane jumps by another $300.00.

[HK111]

Your plane's price won't go up by $300 if that "structural" part would have actually been done right, with maybe 10 grams more of plastic and and a grid of reinforcement ribs so that it would actually do what it is intended for - *safely* holding the most important control surface of a 6kg 200km/h missile...

[RCjetdude]

On my plane it is rock solid...

[HK111]

And by the way, it is MotionRC's + Freewing's job to fix the plane, not ours. It is rather nice of these groups of pilots to work hard to reverse engineer the problem, while the original designers probably had a hunch even after the very first crashes, and probably know completely which trade-offs they made which turned out to be too risky in hindsight.

People should remember that Lanxiang / Sky Flight Hobby once was a respectable company with advanced and audacious foam jet designs. But they made too many compromises, there were just too many quality issues, and now almost no dealer wants to sell their planes anymore.

[janmb]

By your opinion, which would be the better way to balance this jet? With front and back battery or mid and back battery.
Just looking for recommendations. Thanks
hmarmaizmd717

The only way you are going to get even close to make the model actually balanced is in the aft and mid bays, and preferably light batteries.

[janmb]

The people flying this model is why this Jet is crashing.

Yes, if people didn't fly the model, it obviously wouldn't crash.

But no, the crashes we've seen are not pilot errors.

What Fool fly's a Jet full throttle with flaps down?

I do occasionally. But typically at slow speeds and into slow, lazy barrels and such. Flaps and tons of speed on the other hand is something I don't combine.

But it's easy to say that until you get to the day where you forget to pull your flaps after takeoff, fumble the switch or whatever. Even the most brilliant pilots eventually do such mistakes, it's just a matter of time.

Ali Machinchy and Martin Pickering has lost models to mistakes. If they do, absolutely everyone else will - it is just a matter of time. If you are confident you never will - now that is when you actually do have a problem.

What Fool fly's a new jet without getting used to it?

Hard to get used to it without flying it.

What Fool takes the CG marked in the manual as gospel?

99% of the customer base, if not more. Reinforced by vendor marketing presenting it as gold in every occasion they get.

The manufacturer does not make a model nose heavy or tail heavy,,, you do!

Ultimately true, but since you cannot know before you try, and because as mentioned, most customers trust the manufacturers claims in the first place, this does boil down to being a problem created by the manufacturer/vendor, not the customers.

[xviper]

Your plane's price won't go up by $300 if that "structural" part would have actually been done right, with maybe 10 grams more of plastic and and a grid of reinforcement ribs so that it would actually do what it is intended for - *safely* holding the most important control surface of a 6kg 200km/h missile...

Well, let's see. We're not talking about just one piece.................
We want better wiring for all the long servo runs.
We want stiffer elevators.
We want a better balancing plane.
We want better, stronger servos.
We want shielding for RF interference.
We want a different routing for all the wiring.
We want bigger ESCs for more margin.
We want more power in those EDFs.
We want better blue boxes so we don't have to bypass the one that comes.
We want better bracing in the nose gear.
We want stronger retracts all around.
We want more scale looking wheels.
We want stronger nose pointy thing that won't snap off when it hits the grass.
We want better paint that won't come off when we take the masking tape off.
We want another livery for those who don't like the current one.
We want more plastic in places that we get so many finger indentations when we pick the plane up.
We want bigger, stiffer, stronger control arms.
We want a better flap design so that when we forget to put them up and go for a high speed dive, the plane won't crash.
We want leading edge slats so the plane can be more "scale".
And now, we want stronger parts to hold the elevators in.
We want this and we want that......................
Is the sky falling yet? Have we reached 300 bucks yet? Why are any of these Motion's or Freewing's job to give us? This is the nature of the hobby. Take a look at Dynam. When we buy Dynam, we understand what we get and we, as hobbyists, are fully prepare to do whatever it takes to make the product work better and to work the way we want it. So, if we demand a product that we don't have to do this? We end up in another price point. We end up with FMS. We end up with Freewing. Still not good enough? Well, let's introduce "FMWing", another price point higher and maybe we get more of what we demand. Still not enough? We want complete end user instant gratification? Let's go another price point higher. And higher. Till nobody can afford these things anymore. Go talk to turbine jet guys and ask them what they think about their hobby and what they think about their price point and what they think and demand the manufacturers to do for them. It just never ends. There will always be disgruntled customers who demand more.

[mshagg]

Well, let's see. We're not talking about just one piece.................
We want better wiring for all the long servo runs.
We want stiffer elevators.
We want a better balancing plane.
We want better, stronger servos.
We want shielding for RF interference.
We want a different routing for all the wiring.
We want bigger ESCs for more margin.
We want more power in those EDFs.
We want better blue boxes so we don't have to bypass the one that comes.
We want better bracing in the nose gear.
We want stronger retracts all around.
We want more scale looking wheels.
We want stronger nose pointy thing that won't snap off when it hits the grass.
We want better paint that won't come off when we take the masking tape off.
We want another livery for those who don't like the current one.
We want more plastic in places that we get so many finger indentations when we pick the plane up.
We want bigger, stiffer, stronger control arms.
We want a better flap design so that when we forget to put them up and go for a high speed dive, the plane won't crash.
We want leading edge slats so the plane can be more "scale".
And now, we want stronger parts to hold the elevators in.
We want this and we want that......................
Is the sky falling yet? Have we reached 300 bucks yet? Why are any of these Motion's or Freewing's job to give us? This is the nature of the hobby. Take a look at Dynam. When we buy Dynam, we understand what we get and we, as hobbyists, are fully prepare to do whatever it takes to make the product work better and to work the way we want it. So, if we demand a product that we don't have to do this? We end up in another price point. We end up with FMS. We end up with Freewing. Still not good enough? Well, let's introduce "FMWing", another price point higher and maybe we get more of what we demand. Still not enough? We want complete end user instant gratification? Let's go another price point higher. And higher. Till nobody can afford these things anymore. Go talk to turbine jet guys and ask them what they think about their hobby and what they think about their price point and what they think and demand the manufacturers to do for them. It just never ends. There will always be disgruntled customers who demand more.

This is a ridiculous strawman. We want an airframe that doesnt lawn dart under easily achievable flight configurations.

I can replace my own wiring. I can change servos. That's part of the hobby. What I cant do is re-engineer a molded structural component that is glued into the foam at the factory.

I see no reason for anyone to be an apologist on freewing's behalf. They're not your friend, they want a share of your wallet.

[GliderGuy]

The video is a fooler. Study it closely. Watch the bottom of the vertical stab....no deformation of the tail structure.

I’m still gonna add some 0.5 mm sheet CF to the sides and bottom back there but only to harden it against fatigue and/or glue joint separation.

What is shown in the video is the FFS bending down.

-GG

[GliderGuy]

I agree with xviper on the 6000's. If I fly mine with my Admiral 6000 Pro's the forward battery is definitely on the middle tray to attain factory CG and I have not relocated the blue box.

Ditto....Admiral Pro 6000s Middle and aft tray / did not relocate the blue box. Shove batteries as far back as possible AND....added about 60 gm under the rear fuselage. CG = 15 mm aft of mark. Flies fine.
Reduced amount of FFS trim 80%. Still carrying a little....maybe 1 mm. FFS servos no doubt are seeing lighter loads.

Also moved FFS push rods to the innermost hole on the servo arm.

-GG

[xviper]

This is a ridiculous strawman. We want an airframe that doesnt lawn dart under easily achievable flight configurations.

I can replace my own wiring. I can change servos. That's part of the hobby. What I cant do is re-engineer a molded structural component that is glued into the foam at the factory.

I see no reason for anyone to be an apologist on freewing's behalf. They're not your friend, they want a share of your wallet.

First of all, they are NOT my friend nor am I apologizing on their behalf. I'm just presenting a rebuttal and the other point of view, trying to be as reasonable and as logical as I could. Of course, no amount of logic or reason will satisfy some people because they had one target in mind when they posted and that's all they see. As for doing a lawn dart under easily achievable flight configurations, it has not been determined yet what causes these dirt naps. I can only harken back to my days with the Honda S2000. Of the 80,000 such cars sold over the years, a handful of them blew up their differentials. How many? A couple hundred. And yet, the proclamation was that ALL S2000's had bad differentials. It was never proven. That was just the way is was believed. No known cause was ever found, but "Man, don't buy an S2000. They have weak differentials. Just terrible cars."
OK, back to this MiG. How many have been sold? How many have taken a dirt dive? What have been the proven reasons? Doesn't matter. ALL of them have bad airframes. Of course it's HORRIBLE to be one of those who lost a plane for unknown reasons. Of course we all want to find out what that reason is. And some of those points I listed are "straws" to some. You don't think I should grab at them? Well, it would seem that there have been many straws presented and more than a few people have grabbed at them.
You can replace your own wiring, but what about the guy who's frame of mind is such that it's Motion's job to do that? So, you can change servos. But what about the guy who believes that it's Motion's job to do it? (Which, by the way, they did do in one instance.) Sure, you and I can say that's part of the hobby. That was my exact point. When you buy a Dynam, you do stuff to it to make it acceptable. That's part of the hobby. How many Dynams have crashed? When you bought an LX, you do stuff to it. You didn't pay much for it so "that's part of the hobby". How many LX's have crashed? The LX was even the exact example that "HK111" used and yet, he didn't get it. However, some people don't see it that way. Grabbing at straws, you say? In some peoples' minds, it's only straws that they see and they will see nothing else, reason and logic be damned. "This is my bone and I'll pick it to death."
Please remember, I am NOT a Motion FANBOI. I am NOT their cheerleader. I simply want to point out both sides. And in doing so, it puts a dent in certain people's point of view (and egos). Sorry if I've done that to you. But then, that's the way it's been between you and me throughout the history of this and the other forum. And I guess, that's the way it is and it's likely that's the way it shall always be. I'm good with it.

[viper1gj]

Getting close to finishing the turbine conversion with K-45 and 3D printed CL tank. Initial calculations look good for weight and CG of about 13.5lbs TO weight and -15mm from factory. Here are a few happy snaps of the tank and turbine mounting so far.

[mshagg]

And in doing so, it puts a dent in certain people's point of view (and egos). Sorry if I've done that to you. But then, that's the way it's been between you and me throughout the history of this and the other forum. And I guess, that's the way it is and it's likely that's the way it shall always be. I'm good with it.

I certainly dont take it personally and I hope you dont either. Perhaps i made my point poorly. Some thin wiring, a borderline ESC, cheap servos etc to fit within a price point is excusable (if not expected), simple to rectify and typically not fatal. A molded plastic mount for a highly loaded horizontal stab that is potentially a weak spot? Not so much...

Anyway Im designing a brace people can print if the combination of fred's crash video and HK's manipulation of the plastic in question concerns them. I'll post it up on thingiverse when done.

[xviper]

I certainly dont take it personally and I hope you dont either.

Good to know. I appreciate you making that point. Some people just never really see eye to eye on anything. That's what makes the world go round. What really matters is how they treat each other in the process.

[leithalweapon]

I'm with Double G, the elevator is twisting and, if I had to guess, the vertical fins are being pulled outward by a change in air pressure due to flaps being deployed beyond VFE Granted the plastic U channel is allowing some flexing in the fuselage. The Chinese CAD operators haven't learned that an equaleteral triangle is is the simplest and strongest structure. They design some drone frames this way. If your not an engineer using a rectangle shape instead of a triangle shape probably looks just fine on a monitor.
Got a few fligjts on my mig today. This little hick up has made me more mindful of the flap position during flight.