24" span SU27/Eagle/f22 trio - Page 3 - RC Groups
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Oct 24, 2006, 01:06 PM
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davereap's Avatar
Hi jeff
post no 6, the third pic along with the plane upside down shows the linkage. click on the picture to make it bigger.

link 1..goes from the servo arm outer hole.... to the aileron horn inner.
link 2..goes from the aileron horn outer.... to the taileron/elevators inner

so it makes the aileron and elevator go up or down together on the same side.
You need to set the mixing on your tx to enable the elevons, obviously.

I hope youve a set with mixing.

If youve never seen the ikarus setup, this seems weird, but it works just great

I setup the ailerons and elevator in line with the wing and tailplane all flat.
use a couple of bits of balsa and some small spring clamps to hold them all level.
The nylon links are drilled out enough to just make it possible to push the rods through them. must be a tight fit.
The rods are cut so that they are long enough to just come through the links at each end by about 1/8", but not too long to interfear with the horns when moving to and fro
The rods are then glued with CA or hot melt at the inside and outside point of each link.. It doesnt need much glue on the rod to stop it moving in the link
Any trimming is now done using the TX
Last edited by davereap; Oct 24, 2006 at 01:21 PM.
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Oct 25, 2006, 05:32 AM
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Upup's Avatar
This obviously works but dose this not give differing rates on the elevators and aileron or is that the idea?. If so is the horn size and hole spacing critical
Any chance of a close up photo of the linkage ... being all white it is hard to see the setup..... it looks so neat and tidy and there is no point in reinventing the wheel ....
(where is my bottle base glasses) regards
Oct 25, 2006, 07:34 AM
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The way ive set it up will give different movements ..more on the elevators... but it is not at all critical, I just like as much throw as possible, so always go from the outside on the servo to the inside on the horn giving that extra movement on the control surfaces..I Nearly always I have to reduce the thows using the rates to get it to fly as I like, but the option for larger control movements is there for when you want it..

Ive only taken the pic of the centre/aileron horn.. its obvious that if you use the same type of horn on the elevator, you can then put the link in the coresponding/same hole and the angle of movement will then be the same for aileron and elevator
AS I said not critical...
The ikarus version says you can just use elevons (leaving the ailerons fixed to the wing rather than cut out) for control when you like a more sedate flyer

whatever holes you choose just make sure to use the same on the other side
take your choice....dave
Oct 25, 2006, 09:42 AM
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Upup's Avatar
Cheers Dave
Oct 25, 2006, 02:02 PM
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Ive started to draw up the f15 from the plans onto the foamboard I use, its depron paper covered, cut out then soak off the paper, a pain but I got a cheap lot...

I now realise there are loads of measurements I should have put onto the drawings and forgot
if you need the measurements download the free A9cad program and open the drawing.... measure from there

a9cad at http://www.softpedia.com/get/Science-CAD/A9CAD.shtml

still I kept the basic outline as near as possible and made some more mods as I went along to get nearer the outlines in my book...

Ive posted the small pic but if anyone wants the full thing 3meg I will email it to you

mods on this one...the elevators come even more across towards the centre of the fuz.. aileron shape changed slightly to look better, front fuz has cutouts to indicate the intakes, and is curved to the wing, as is the real thing

As I said before the only important bits are looking from the top
the main wing triangle,
the rear fuz
the tailplane
and the COG position
you can change the ailerons, elevator, body shape how you like, within reason of course.
if it looks ok it will be

I can never make anything without making some small mod
Last edited by davereap; Oct 25, 2006 at 02:08 PM.
Oct 25, 2006, 02:33 PM
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ive now cut out the two main sections, the ailerons and elevators will be cut away before I strip the paper.
now to draw up the various fuz sections, horizontal and vertical, and the lower cross brace
Last edited by davereap; Oct 25, 2006 at 02:41 PM.
Oct 25, 2006, 04:19 PM
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cut out all the fuz bits... reading top to bottom left to right

vertical outer fuz/tails x2
front inner vertical fuzes x2 ...go along the engine intakes sides from front of intake to under wing part way
front fuz horizontal x2 should have been one bit...whoops..will cut that again
top and bottom vertical fuzes
lower cross brace

made a few more changes to the fuz shapes, again to give a simpler cut and design,when compared to the drawings..I will have to redo the drawings more specific to the f15.
Last edited by davereap; Oct 25, 2006 at 05:21 PM.
Oct 26, 2006, 12:00 PM
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sweet I love that jet cant wait to hear how it flies. still working on that su-27 thanks. I decided to scale down the plans so hopfly I can fly it in small places (not quite an indoor) 13.5in wing isn't that small is it? o well should be fun anyways
Oct 26, 2006, 12:45 PM
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ive done a bit more to the plans on post 23 so they are slightly revised..

please update your versions....dave.. updated plans now at post 23

I will do some simplified plans for each part now.. but I am not so good with the cad program so will put the corect sizes in my text if my drawing is slightly off

the reduced size version is going to be the ikarus shock flier that started me off.. build with 3mm depron... scale down to suit your engine/prop
Last edited by davereap; Oct 27, 2006 at 11:40 AM.
Oct 27, 2006, 11:10 AM
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ive simplified the drawings to show some of the parts better

the first drawing shows the main wing, rear top fuz/decking, tailplane..with the ailerons and elevators in position
one of each is needed

the cog is shown where the circles are and should be 4 1/2" forward fron the back edge of the wing triangle

drawing 2 shows the vertical fuz sections. .. top and bottom main body,outer lower fuz/tail and inner front fuz in red for the f15.
you need one each of main body, and two each of the others.
Its worth cutting the f15 intake strakes as they can be used on the su27 to double the front of the outer fuzes, and will support the lower front cross section better
the lower main fuz and the inner front fuzes should be 1 1/4" deep, all cut straight for the lower cross brace to sit on
Last edited by davereap; Nov 04, 2006 at 11:47 AM.
Oct 27, 2006, 04:06 PM
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I have got out the glue and built the f15 version I previously cut out
... the only fault I see now its finished is that by shortening the nose / body length slightly, only 1", but it doesnt look quite right...
So if you build one you need keep the overal length of the nose/body the same as on the su version, or even go up an inch. just cut the shape to represent the f15 better..

pic1...CF reinforcement stuck to wing and rear outer vertical fuz slotted with the rear horizontal fuz...uhu

pic2 ..wing and nose with botton vertical fuzes attached...uhu

pic3 .. rear horizontal fuz/tailplane with outer vertical fuz/tails attached...uhu

pic4 .. the two prebuilt sections are now joined...uhu

pic5 .. the lower front cross piece is fitted...uhu

pic6 ..the top front vertical fuz is fitted...uhu

pic7 .. the elevators and ailerons are fitted with sticky tape

pic8 ...A 2" section has been spliced into the nose area and the shape slightly changed.
two CF rods are also being glued on either side of the lower front fuz, they can just be seen banded at the front

the extra 2" makes all the difference
Last edited by davereap; Oct 27, 2006 at 05:43 PM.
Oct 27, 2006, 05:57 PM
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All that remains of the build is to smooth the edges and do all the tape reinforcing.
plus the cf outer fuz reinforcement.
plus mounting the motor and radio gear
plus the decor

I will use one layer of 2" clear tape top and bottom on the leading edge of the wing with a small wrap around. I will use one layer of 3/4" on the rest of the exposed edges, except for the bottom of the fuzes where I put a couple of layers

I also use the 3/4 tape both sides along all the joints
It is probably more tape than you need but better safe than sorry and it does not add too much weight

weight at the moment 92gms
Last edited by davereap; Oct 28, 2006 at 09:07 AM.
Oct 28, 2006, 09:09 AM
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made a block to fit the motor mount.
fitted in place.
cut the slot for the prop.
glued the CF rods along the outer fuzes
Nov 04, 2006, 11:39 AM
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Tapeing, decoration and finally the radio gear all fitted.

for a change I used a camo paint scheme on the f15, I did the top in it, didnt like it much, and so did the bottom with the 2" coloured packing tape as I normally would.

anyone got a good colour scheme for the f15...best ive found which would suit the tape method is the NASA one ...see pics

all up weight 6 1/4 oz (no battery)

revised COG for first safe flight...4 1/2 inches, measured forward from the aileron hinge line/ CF mian spar
Nov 06, 2006, 08:38 AM
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I have just maidened the f15 version and the increased response due to the elevators having more area in the prop wash is amazing. I have had to dial down the rates on both ailerons and elevator to about 40% and have also put in about -30% exponential.
At the reduced settings it is still more responsive than my original SU version, so be aware of this and decide if you want the additional response or not.

If you want a less responsive model, still with plenty of control, cut the elevators to start 1" inside from the tail. or more response 2 1/2" in..check out the middle photo above

On the first flight I thought I had the cog too far back because it was so twitchy. but this was not the case. it just needed the lower rates and softening with exponential
Last edited by davereap; Nov 06, 2006 at 09:00 AM.

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