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#1 amzimmy Aug 20, 2007 08:49 AM

Eagle F3B X-tail
Hi Guys, have just purchased a brand new Eagle F3b plane from Jiri Tuma, Czech Republic. I was wondering if anyone of you has this particular plane and if I could get some hints, details and perhaps some modifications that would improve the the performance. Maybe settings of the control surfaces like ailerons, flaps, rudder, elevator, spoilers and butterfly settings (craw-flaps).
I'll be very thankful.


#2 oakman7004 Aug 21, 2007 02:07 AM

Try contact Jiri: Tuma Homepage

Or designer Guenter Aichholzer : Guenter

They should be able to help you...

/Jonas Ekman

#3 amzimmy Aug 21, 2007 04:02 AM

Thanks for the tip Jonas, I have downloaded the general set-up from Guenter. I looks there are very few "Eagle" around. Not to sound too "blond", I was looking for for any mods or improvements before I tackle the building process.


#4 Wing-span Aug 21, 2007 10:20 AM

Post a thread regarding the build in the Multi Task F3X forum area.

You are bound to get some answers there!


#5 S-1-11B Aug 21, 2007 11:31 PM

Hi amzimmy,

I just purchased one from Skip Miller here in the US. I really like the lines of the plane and the build quality is great. Not quite like my Superior, but not much difference at all.

I only got it about two weeks ago and am close to finishing the build. The one area where I think I might have learned something not so obvious in the build is the location of the fuselage servos.

Side by side, a JR 3241 and JR 368 (rudder) fit just fine with short horns on them. I still need to measure, but I think that this length arm is not enough to produce enough throw (even at 150% in my JR 9303) on the elevator. Rudder is fine. A longer arm will rub on the nose cone. On Skip's page, he shows an offset to the servos and longer arms. I will post again when I measure, but be sure you keep an eye on this one.

I have not done the set up but plan to use the throws shown on Jiri's page as a starter.

I plan to maiden the plane this weekend. Good luck with yours.


#6 amzimmy Aug 22, 2007 12:33 PM

Thanks Wingspan will put the thread on F3X.

Sean, hey thanks, I just had a look at this point too. I've started with the building and had my two servos (Micro digi from MPLX) for rudder and elevator side by side, however with some measurements , before cutting, I discovered that the arms would be too short. So I opted for the one behind the other just off-set them to have a long enough arm. The rest fitted well, receiver RX-7 Synth IPD, fits beautifully in, the batteries, 5 AA Ni-MH. 1900 mAh, I have placed in line 2+2 (side-by side)+1 partly under the receiver. Giving me good space for the nose weight. Do you know how much weight is necessary? On my two Trinity V & X I had to battle to put enough weight!
The other thing that I have done is run a plastic clear tubing in the fuselage to insert the aerial. Lengthened the aerial by 90 cm , run the tubing past the rudder control horn and "hot-glued" the aerial in the inside channel between the rudder control surface and the fin. On the top of the fin I made a small hole (1 mm dia) and fitted a 0,5 mm dia steel rod, about 300 long that I have soldered to the end of the aerial and use this as an external aerial.
I am now busy with the one wing. As servos, for ailerons and flaps, I intend using the HiTec HS-125MG with ball link connection. I have made special plywood tray for mounting the servos. For now everything fits and is looking good.
There is a little questionable difference between some people, the CG point, some say 90 cm some say 95 and some 97. Have you had better info on this?
If I can, I plan to have the maiden flight this weekend as well.

Happy soaring!


#7 Wing-span Aug 23, 2007 03:09 AM

I guess you mean mm not cm for the C/G position.

Make sure you retract your flaps just before touch down because those servos are known to be delicate (easily strip gears) though they will work.

It should fly really well!!

#8 amzimmy Aug 23, 2007 07:25 AM

Yes, mm and not cm, I guess a "senior" moment. Yep the flaps saga will be, unfortunately, the same as for the Trinity, big spoilers and qiuck reaction. I found that the gears for the HS-125MG servos are the same as the Graupner and JR wing servo and the replacement gears are quite easy to get, and quite easy to replace. Thanks for the advice, it is always appreciated!


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