Hitec 65MG servo specs (25oz in @ 4.8V, 31oz in @ 6V)
Recommended JR MC 35 specs (30oz in@ 4.8v, 35 oz in @ 6V)

The same MC35 servos were recommended for the Habu32. However, the control suraces for the F4 wing are about 3/4 of the size of the Habu.

I appreciate everyones thoughts on this.

Jim

Originally Posted by Gibb

Hitec 65MG servo specs (25oz in @ 4.8V, 31oz in @ 6V)
Recommended JR MC 35 specs (30oz in@ 4.8v, 35 oz in @ 6V)

The same MC35 servos were recommended for the Habu32. However, the control suraces for the F4 wing are about 3/4 of the size of the Habu.

I appreciate everyones thoughts on this.

Jim

Those servos are good for a plane/jet 6 pounds and under. You want the 85 series of Hi-Tec servos in this plane. Read the Habu 32 threads and make up your own mind... the 85mg is the solution here.

For my Habu 32 I used HS65 MG's for ailerons and elevators, HS85 MG's for flaps. All on 6 volts. All my flying is on low rates (minimal surface movement). I would not use HS65 MG's on the flaps.

Hey Guys,

Want some opinions, I am just finishing up my F4. Last step, I am putting on the retracts.

Did you guys use the stock screws? Did they fix the problem where the tops broke off, like on the Habu? I know bwana used different ones, but if they fixed the problem, I would like to use the ones with the kit.

Let me know what you think?

Originally Posted by stvinvegas

Hey Guys,

Want some opinions, I am just finishing up my F4. Last step, I am putting on the retracts.

Did you guys use the stock screws? Did they fix the problem where the tops broke off, like on the Habu? I know bwana used different ones, but if they fixed the problem, I would like to use the ones with the kit.

Let me know what you think?

I repalce with better screw.
Make sure to drill 1/16" pilot hole.

420 I'm with you, I don't really even like the look of the gear doors.

Originally Posted by Tamjets

I repalce with better screw.
Make sure to drill 1/16" pilot hole.

Thanks Tam, thats what I thought. Better safe then sorry, that was the worst part of the Habu build. Broke off a couple before I knew it.

When securing the wing spar in the fuselage, how tight is everyone making these bolts. Since they press against the carbon fiber spar, I'm afraid of damaging it. Any tips or knowledge would be appreciated. Thanks.

Originally Posted by KentF

When securing the wing spar in the fuselage, how tight is everyone making these bolts. Since they press against the carbon fiber spar, I'm afraid of damaging it. Any tips or knowledge would be appreciated. Thanks.

As tight as I could get them, won't hurt that carbon fiber

Originally Posted by KentF

When securing the wing spar in the fuselage, how tight is everyone making these bolts. Since they press against the carbon fiber spar, I'm afraid of damaging it. Any tips or knowledge would be appreciated. Thanks.

What tool did everyone use, and how the %&%8 do you get your hand in there?

Also locktite blue, right?

Originally Posted by 420flyboy

As tight as I could get them, won't hurt that carbon fiber

I did that and stripped one on the habu, had to go with a bigger bolt. Sometimes you don't know your own strength, so not crazy tight, they can strip.

Originally Posted by 172AMD

For my Habu 32 I used HS65 MG's for ailerons and elevators, HS85 MG's for flaps. All on 6 volts. All my flying is on low rates (minimal surface movement). I would not use HS65 MG's on the flaps.

Sorry for the off-topic. When I updated the Habu to 8S ..I update the servos too...that being said..I still only use these 65MG for planes/jets under 6 pounds..better safe then sorry..get the 85 MG's for your expensive Bird's guys or the best ones you can afford!!... the next round of servos will be HV in the 85 series...no more regulator on the next Jet Build.

Originally Posted by stvinvegas

What tool did everyone use, and how the %&%8 do you get your hand in there?

Also locktite blue, right?

LOL! Getting these bolts in was the hardest part of the build. I am 6"5" with big hands and feet. I just couldn't get them in. I finally resorted to my least used, most expensive tool. I called in my 5'3" Wife with her small hands. She got them right in. I have a feeling it is going to cost me some day. LOL!

I used a ball driver to tighten them up. It is the only way.

Yes, blue Loctite on all metal to metal in the plane.

I just finished programming my F-4. I used the AR-8000 DSMX RX as suggested in the manual, and set my servos up as recommended in the manual. This means that the aileron servos are set up with opposite orientation so they can run off a "Y" harness.

My guess is that HH did this to support the DX-8 Spektrum radio, not because it gets you the best setup. When you get to the reccommended throws for the ailerons the manual calls for a couple of millimeters of differential. More throw up than down. This is usually done to take caare of rolling issues that cause the plane to pull slightly off line during rolls. However, since the ailerons are on a "Y", you cannot put in this kind of differential. I ended up having identical throws up and down. I'm not sure if this will be an issue because I haven't flown the plane yet. Hoefully it won't matter much. Still, for those that have a high channel radio like the 11X, I suggest you use at least a 9 channel RX. This way you will have complete control of the entire setup.

I also found that even with the longest arms on the Hitec HS-85 servos you will have trouble getting the full 30mm of throw for the flaps. I ran out at about 28mm. Once again, it probably won't matter.

One final thing. The manual calls for Up Elevator compensation with flaps. The habu-32 required down Elevator compensation which worked perfectly. Have you guys who have flown this plane think the Up Elevator is correct for this jet?

I will post my 11X file as soon as I have done the maiden and gotten it all dialed in.

Originally Posted by 1bwana1

I just finished programming my F-4. I used the AR-8000 DSMX RX as suggested in the manual, and set my servos up as recommended in the manual. This means that the aileron servos are set up with opposite orientation so they can run off a "Y" harness.

My guess is that HH did this to support the DX-8 Spektrum radio, not because it gets you the best setup. When you get to the reccommended throws for the ailerons the manual calls for a couple of millimeters of differential. More throw up than down. This is usually done to take caare of rolling issues that cause the plane to pull slightly off line during rolls. However, since the ailerons are on a "Y", you cannot put in this kind of differential. I ended up having identical throws up and down. I'm not sure if this will be an issue because I haven't flown the plane yet. Hoefully it won't matter much. Still, for those that have a high channel radio like the 11X, I suggest you use at least a 9 channel RX. This way you will have complete control of the entire setup.

I also found that even with the longest arms on the Hitec HS-85 servos you will have trouble getting the full 30mm of throw for the flaps. I ran out at about 28mm. Once again, it probably won't matter.

One final thing. The manual calls for Up Elevator compensation with flaps. The habu-32 required down Elevator compensation which worked perfectly. Have you guys who have flown this plane think the Up Elevator is correct for this jet?

I will post my 11X file as soon as I have done the maiden and gotten it all dialed in.

Hi,

You can still achieve Aileron Differential using Aileron servos on a Y harness, reset you neutral point on both your servo arms towards the front/nose of the airplane or away from the aileron (move the servo arms one or two notches on the spline and lengthen your push-rods). The more you move them the more differential you will get. Play with the angles until you get the recommended differential and then when you fly the plane you can increase or decrease it to your liking.

The right hand side of this picture illustrates this:



- Birger