Official Freewing 90mm F-4 Phantom II Thread

[Elbee]

vduniec, Nice job on the "Rhinoplasty". She's really looking the part. Best, LB

[RCjetdude]

Vic, your Phantom is looking really good. Next time you are headed to the mountains give me a shout.

[e4dragongunner]

Wow!!!
Beautiful!

[billd3]

After setting up my 90MMF-4 I decided to change receivers.I installed a new Admiral DSMX™ compatible stabilized gyro receiver. Following the binding process everything came to life as expected. I then noticed I didn't have a pigtail connecting the thro. ch on the Rx to the thro ch. on the main board. but I had the Esc's BEC plugged into the main board on the aft pins (between the wing plug-ins. Since I couldn't remember how I had things originally plugged in, I installed a pigtail from the RX to the main board servo pins and since I neglected to remove the bind plug I had to rebind the Rx. All was fine EXCEPT I had NO throttle response. I experimented with the BEC's plug placement and the newly installed Throttle pigtail in several different ways but NO JOY. I re bound the Rx a couple of times...again No Joy on the throttle plus the elevator servo started going wild...another re bind attempt and everything was working again...EXCEPT the throttle...What have I done wrong???
Bill

[billd3]

BTW: the UBEC plug (the one with the iron ferrite ring)...there is a throttle pins on the main board between the wing connection wires and also one on the servo pin area of the main board. Where, exactly do you plug the BEC in? My F-4 did not come with a pigtail to connect the throttle pins on the Rx and the one on the servo pin section???
Thanks in advance...Sorry to such a PIA.
Bill

[locharrow]

BTW: the UBEC plug (the one with the iron ferrite ring)...there is a throttle pins on the main board between the wing connection wires and also one on the servo pin area of the main board. Where, exactly do you plug the BEC in? My F-4 did not come with a pigtail to connect the throttle pins on the Rx and the one on the servo pin section???
Thanks in advance...Sorry to such a PIA.
Bill

I plugged the esc bec lead directly to the rx throttle port....don't see the point in what seems to be unnecessary connections from the rx to the esc through the two boards. If you do that and it doesn't work try an rx you know is working and plug the esc bec into the throttle channel ...If it is the esc that needs programming you will hear tones but no whoosh! If you don't get tones or whoosh try a new esc.

[billd3]

I plugged the esc bec lead directly to the rx throttle port....don't see the point in what seems to be unnecessary connections from the rx to the esc through the two boards. If you do that and it doesn't work try an rx you know is working and plug the esc bec into the throttle channel ...If it is the esc that needs programming you will hear tones but no whoosh! If you don't get tones or whoosh try a new esc.

Thanks...I gave it a lot of thought last night and here's what I did... I made a 4" double male lead and plugged this into the Rx and in the Rx pin line for Throttle. I then plugged the ESC into the pins on the servo line (the ones in the back). I discovered an unplugged wire coming from the back of the fuse with white/red/blk wires and plugged it into the other throttle pins on the servo line of the main board. I then put the bind plug back into the Rx and re-bound it to the Tx. Everything came to life.Yahoo. I figured by doing that I would be using the buss in the main board for the power loads(???) and that might be more robust than the buss in the Rx. I'm an electronic idiot, however...So could someone of more knowledge confirm this thinking or point me in another direction? I can be dangerous when I start thinking about such things
Bill

ps: Now the only issue is a dead spot in the throttle on the low end (about a quarter inch of stick movement. I tried to re calibrate the ESC following the instructions on the Knowledge Blog but , No Joy????

[Waconut]

When you do the calibration are you getting the 2 beeps with the throttle at full throttle when you power up the esc ? And then the beeps when you drop the throttle to the off position ?
I have not had an issue when calibrating any of my stock esc’s.

[locharrow]

" I figured that by doing that I would be using the buss in the main board for the power loads(???) and that might be more robust than the buss in the Rx. "

I don't like overloading the rx either. I run a separate bec to power the U/C just using the + & - wires from the bec and the signal wire from the rx soldered to a connector then plugged into the board. Bit similar to the twin bec I use in my the SU 35 ...think it has about eleven servos and three gear units ... nothing that doesn't move on it !!

[Hugh Wiedman]

Thanks...I gave it a lot of thought last night and here's what I did... I made a 4" double male lead and plugged this into the Rx and in the Rx pin line for Throttle. I then plugged the ESC into the pins on the servo line (the ones in the back). I discovered an unplugged wire coming from the back of the fuse with white/red/blk wires and plugged it into the other throttle pins on the servo line of the main board. I then put the bind plug back into the Rx and re-bound it to the Tx. Everything came to life.Yahoo. I figured by doing that I would be using the buss in the main board for the power loads(???) and that might be more robust than the buss in the Rx. I'm an electronic idiot, however...So could someone of more knowledge confirm this thinking or point me in another direction? I can be dangerous when I start thinking about such things
Bill

ps: Now the only issue is a dead spot in the throttle on the low end (about a quarter inch of stick movement. I tried to re calibrate the ESC following the instructions on the Knowledge Blog but , No Joy????

Regarding the "dead spot" at the bottom end of the throttle, I assume you mean that you need to advance the throttle quit a bit before it starts. Since you already calibrated the ESC, I have another suggestion. Virtually all of my planes/jets need the throttle to advance some before they start (about 5-10% if you look at the top of the main screen to see where the throttle is at, with of course 100 being full throttle). What I do with the majority of my planes (especially the 3D Extreme Flight planes) is advance the throttle trim to the point just before the prop starts turning. This is actually recommended by Extreme Flight which gives you "better throttle sensitivity at low throttle stick points, a must in 3D flying). I also do this with all my tail dragging warbirds because they all have the sound system in them and when I take the throttle cut off (to on), I want the sound to start and the prop to just barely turn. Additionally, the sound then won't shut down when the throttle is reduced to all the way down. If you do this, you must remember to return the throttle trim to 0 at the end of every flight, so when you power it up for the next flight, the ESC will not have to be re-calibrated.

[vduniec]

Ready for inspection! Here's the final product. Weapons, "E" nose, cockpit, pilots, TIESO and centerline tank are 3D printed. Only one flight on it so far. It has survived the maiden but was pretty nose heavy and I bounced the landing shearing the nose gear pin. Already repaired and ready for the next sortie.

[Alpha]

Another masterpiece, vduniec ! Your conversion and loadout compliment the livery so well.

[Aros]

Beautiful. Outside of the 80mm A-10, this F-4 has to be my all-time favorite Freewing EDF to date.

[Elbee]

vduniec, Beautiful work, just outstanding. Best, LB

[sfcbhunt]

637529 F-4C as she was at William Tell, 1982. 191st Fighter Interceptor Group out of Selfridge ANGB, Michigan. The bird is "wrapped" in Scotchcal 2020 self stick film, which is a touch thicker than the stuff Callie uses. Estimating about 400 separate pieces to do the job. Took about 2 months.

Maidened today. The 7.5" CG is no good. Second flight, moved the battery up as far as it will go and still not stable in pitch. Vicious roll to the left, ended up with 1/4" right aileron trim. Not impressed so far.

Will move CG further forward, and use combined flap and aileron trim 1/4" on the right side. Hoping to cure it this way and have neutral trim on the left. The adverse yaw associated with left aileron down makes turning right no fun.

[Hugh Wiedman]

637529 F-4C as she was at William Tell, 1982. 191st Fighter Interceptor Group out of Selfridge ANGB, Michigan. The bird is "wrapped" in Scotchcal 2020 self stick film, which is a touch thicker than the stuff Callie uses. Estimating about 400 separate pieces to do the job. Took about 2 months.

Maidened today. The 7.5" CG is no good. Second flight, moved the battery up as far as it will go and still not stable in pitch. Vicious roll to the left, ended up with 1/4" right aileron trim. Not impressed so far.

Will move CG further forward, and use combined flap and aileron trim 1/4" on the right side. Hoping to cure it this way and have neutral trim on the left. The adverse yaw associated with left aileron down makes turning right no fun.

Outstanding looking job, just beautiful. Your vicious roll to the left is very curious, especially having so much trim without stopping it. There must be something off centered, the F-4 isn't that messed up. This is probably going to sound stupid, but are you absolutely sure the elevators are perfectly equal in position and travel. I had the set screw come slightly loose on the right elevator once and it suddenly corkscrewed something awful, even from being only slightly off. Somehow managed to end up in a hover 6 feet off the ground (don't ask me how, it just happened) and killed the power with only minor damage, but "loaded" pants. First thought it must be something with the ailerons, but finally realized one elevator was slightly loose on the shaft.

Also surprised about the CG, I fly both my F-4's with a 800g Roaring Top 6250mah battery and 192mm from the leading edge and that seems to be the sweet spot for me. I think that's about 7.56" so we're close. Are you flying it with the ordinance fully loaded? One last thought, are you sure that the elevator servo is glued in tight? After about 50 flights with my F-4 Blue Angel, the servo started coming loose and that's when it got very pitch unstable. First thought I might be too tail heavy, but quickly found that the loose servo allowed the elevator to move 5-8 mm on it''s own.

[sfcbhunt]

Thanks, Wildman. I'll check all that. I fly it the way it is in the pic, with tanks and the AIM 9 launchers, and one missile per side.

[sfcbhunt]

Checked everything in the tail section- servo tight, both elevators 3/8" up from the reference point, tight on the shaft. Servo does have a little slop in it, but no more than most servos. I moved the pushrod to the inner most hole so as to give the servo a little more leverage and to slow things down. I'm running about 55% expo.

This is all kind of weird. I've flown a LOT of delta wings (I had an affair with Laddie Mikulasko's Arrow that lasted about 10 years. Built at least a half dozen of them) and there's two things I learned about deltas (and swept wings): They are sensitive to roll inputs, and they are insensitive to pitch inputs. This one is breaking the rules.

[Hugh Wiedman]

Thanks, Wildman. I'll check all that. I fly it the way it is in the pic, with tanks and the AIM 9 launchers, and one missile per side.

This is quite weird. Maybe someone else out there has an idea. The F-4 should be a fairly stable flying jet once you get the CG down. Just can't imagine having to use that much trim. You may want to fly it next time clean, with no tanks or missiles. I do fly mine with the missiles only, and have yet to strap the tanks on because I've heard here that the tanks add quite a bit of drag, but shouldn't affect the roll as drastically as you've got. Keep us posted, very curious as to what's going on there. Best of luck!

[sfcbhunt]

I glued the tanks on, as one of them was pointing lower than the other and I had to shim it. Anyway, this aircraft was never seen without the drop tanks, so I kind of want it that way.

What do they use to hold the elevator servo in? I was thinking of replacing it with a HiTec low profile standard size. Much smoother and no slop.