Official Freewing Twin 80mm F-14D Tomcat Thread

[rifleman_btx]

Storing trims for flight modes?

Yes, that is what I was referring to.

[vicentel]

Very interesting what you are doing, removing the retract type "servos" that are only two position and replacing them with high torque servos to get more than two positions of wing sweep. The original retract servos "lock" at their end points to give holding power. You are relying on the servo to have sufficient holding power.

What servos did you end up using? Are you sure that moving the ball link under the servo arm isn't causing issues?

In your video you had 180deg travel servos moving less than 90deg for the full sweep. A servo can provide much more torque and resolution having the ball link closer to the servo shaft. That may be something to consider. Also if the servo turns to the point that the servo arm is more in line with the push rod it has more holding power. when the arm is 90deg to the pushrod it has the least amount of holding power. Any more pictures or videos?

I ended up using Savox SW1212SG-BE - Waterproof, High Torque, High Voltage Coreless Digital Servo rated at 36kg @6V. If I wanted to dedicate a 2S Lipo pack then the torque goes up to 46kg. But I figured 36kg is more than enough for this application.

From the Savox support site FAQ:
Q. Why does my Savox servo buzz?
A. The buzzing sound is created by the servo constantly making corrections to hold it's position. It is normal with digital servos, but some servos are louder than others.

I am using a shorter servo arm compared to the one used by Freewing (std is 1.25" center hole to ball-link) for the reasons you outlined (more torque higher resolution). I've had 3 successful flights so far. I was monitoring battery usage to see if the high torque servos put too much of a drain on the battery feeding the ubec. But so far the battery drain is negligible. What I would like to do (eventually after much testing) is setup a mix with the swing servos and the throttle (with a delay so the change in the sweep doesn't jerk the wings), keep the endpoint override for landing purposes.

Cheers
Vic

[Evan D]

Very interesting what you are doing, removing the retract type "servos" that are only two position and replacing them with high torque servos to get more than two positions of wing sweep. The original retract servos "lock" at their end points to give holding power. You are relying on the servo to have sufficient holding power.

What servos did you end up using? Are you sure that moving the ball link under the servo arm isn't causing issues?

In your video you had 180deg travel servos moving less than 90deg for the full sweep. A servo can provide much more torque and resolution having the ball link closer to the servo shaft. That may be something to consider. Also if the servo turns to the point that the servo arm is more in line with the push rod it has more holding power. when the arm is 90deg to the pushrod it has the least amount of holding power. Any more pictures or videos?

[vicentel]

There might be some binding at the end of the stroke and the servo is tying to hold it at that position, or the wings are at full movement and the servos are over driving them. check it out.

R.

I checked that the wings are at full movement and the servos are not trying to push them past their limits, at both end points. I use to have the ball ends on top of the servo horn but it was causing binding (twisting) and one of the endpoints so I moved the ball end to the bottom of the servo horn.

[RRHandy]

It's actually louder when the servos are under load. But that buzzing is there even when the servos are not under load and it only happens at the endpoints. Someone mentioned that it was the servos holding their position, but I don't hear the buzzing when the servos are in their mid position. So I'm not sure. This is also my first time using high torque steering servos for this application so I don't have much experience with them. Thoughts?

Vic

There might be some binding at the end of the stroke and the servo is tying to hold it at that position, or the wings are at full movement and the servos are over driving them. check it out.

R.

[vicentel]

Nice work Vic!

I kept help but ask, is it ok for the servos to be buzzing that much?

It's actually louder when the servos are under load. But that buzzing is there even when the servos are not under load and it only happens at the endpoints. Someone mentioned that it was the servos holding their position, but I don't hear the buzzing when the servos are in their mid position. So I'm not sure. This is also my first time using high torque steering servos for this application so I don't have much experience with them. Thoughts?

Vic

[thisguy65]

So I decided to start this little project. I was able to find an L-shaped aluminum bar stock, a couple of High Torque Savox standard size servos (which includes the metal servo arm). I was able to construct a bracket and base the mounting holes on the standard out-of-the-box bracket. I was able to get everything to fit and programed the mid-sweep and tied it to my flight mode switch. The servos pictured here are not the final ones I used, these though we strong had no holding power. I did manage to maiden my F-14 with this mod and was successful. I'll try to get some video of the flight when I get back from my business trip.

https://www.youtube.com/shorts/E9WcSrVxeKc

https://www.youtube.com/shorts/iY5Lbjx9gE0

Cheers,
Vic

Nice work Vic!

I kept help but ask, is it ok for the servos to be buzzing that much?

[kallend]

Storing trims for flight modes?

In that case, already answered:

https://www.hobbysquawk.com/forum/rc-airplanes/rc-military-jets/1800-official-freewing-twin-80mm-f-14d-tomcat-thread?p=343765#post343765

[Evan D]

Storing trims for flight modes?

[kallend]

There has to be, my frsky does it, I would think a bigger company like spektrum would definitely have it as well.

What is this a reply to?

[rifleman_btx]

There has to be, my frsky does it, I would think a bigger company like spektrum would definitely have it as well.

[kallend]

Originally posted by Danonino View Post
Greetings,

I’ve been flying the FW F-14 for a few months and have a question about flight modes:

I use 3 modes - takeoff (high rates, 10° flaps), cruise (medium rates, gear up, flaps up) and wings swept (low rates, flaps disabled).

Each flight mode, specifically with wings swept, require different trims. Will my NX10 store the trim settings for each flight mode?

Yes. Go into Trim Setup (from the setup menu screen) and set the trim type to "F Mode" instead of "Common".

So, did it work out OK?

[pullupnow]

So I decided to start this little project. I was able to find an L-shaped aluminum bar stock, a couple of High Torque Savox standard size servos (which includes the metal servo arm). I was able to construct a bracket and base the mounting holes on the standard out-of-the-box bracket. I was able to get everything to fit and programed the mid-sweep and tied it to my flight mode switch. The servos pictured here are not the final ones I used, these though we strong had no holding power. I did manage to maiden my F-14 with this mod and was successful. I'll try to get some video of the flight when I get back from my business trip.

https://www.youtube.com/shorts/E9WcSrVxeKc

https://www.youtube.com/shorts/iY5Lbjx9gE0

Cheers,
Vic

Oh yeah! That's awesome!

[vicentel]

Hi Guys - Thanks for the quick replies. What I mean is I want to be able to proportionally control the swing of the wings. Rather than having the "landing gear" type mechanism (2 position) that they are currently where they are either fully swept or fully forward. But I would be happy with a 3 position wing with a mid-sweep setting.

My thinking is along the lines of removing the current swing wing servos and replace them with 2x high torque servos (I found 35kg stall torque @ 6V). Use long aluminum servo arms that clamp on to the spline (~1.25"-1.5"). I would have to design a way to mount the servos, probably 1/16" (~1.5mm) thick aluminum plate.

Cheers,
Vic

So I decided to start this little project. I was able to find an L-shaped aluminum bar stock, a couple of High Torque Savox standard size servos (which includes the metal servo arm). I was able to construct a bracket and base the mounting holes on the standard out-of-the-box bracket. I was able to get everything to fit and programed the mid-sweep and tied it to my flight mode switch. The servos pictured here are not the final ones I used, these though we strong had no holding power. I did manage to maiden my F-14 with this mod and was successful. I'll try to get some video of the flight when I get back from my business trip.

https://www.youtube.com/shorts/E9WcSrVxeKc

https://www.youtube.com/shorts/iY5Lbjx9gE0

Cheers,
Vic

[kallend]

Greetings,

I’ve been flying the FW F-14 for a few months and have a question about flight modes:

I use 3 modes - takeoff (high rates, 10° flaps), cruise (medium rates, gear up, flaps up) and wings swept (low rates, flaps disabled).

Each flight mode, specifically with wings swept, require different trims. Will my NX10 store the trim settings for each flight mode?

Yes. Go into Trim Setup (from the setup menu screen) and set the trim type to "F Mode" instead of "Common".

[Danonino]

Greetings,

I’ve been flying the FW F-14 for a few months and have a question about flight modes:

I use 3 modes - takeoff (high rates, 10° flaps), cruise (medium rates, gear up, flaps up) and wings swept (low rates, flaps disabled).

Each flight mode, specifically with wings swept, require different trims. Will my NX10 store the trim settings for each flight mode?

[Evan D]

Sorry I asked.

[rifleman_btx]

I would assume he meant that one of the solder connections on one of the EC5s broke.

Correct. Battery side from the factory.

[crxmanpat]

I would assume he meant that one of the solder connections on one of the EC5s broke.

[rifleman_btx]

What else would it mean?