Espritmodel.com Telemetry Radio
Reply
Thread Tools
Old Oct 06, 2005, 06:06 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
(continued from previous page) Aileron Modification – 2 Choice Of Size Of Ailerons

When a plane is going slowly, small ailerons have minimal effect. The Easy Star, having a low wing loading, can fly very slowly. Bigger ailerons will continue to have effect, even if going slowly. Also, if I glitch close to the ground, I don’t want to be without control. They also help produce the rapid roll rate I required.

The Easy Star has a great wing section with under-camber, ie the underside of the rear of the wing is concave, giving good lift properties at low speed. However it gets draggy at speed and I would like high speed as an option, for windier days, on the slope and just general hooning. By making the ailerons full width, and also using them as flaps, I could adjust the camber of the wing. This would allow me to switch from the current high-lift but draggy wing section to a faster profile – and even select an under-cambered-when-inverted section!

Using my computer radio, with the second aileron on a separate channel I can switch these in and out in flight. Even without this in-flight capability, if I were running both ailerons on one channel, I could choose the camber I wanted to fly on the day and adjust linkages on the ground for a floaty flight or a fast one. Excellent for whatever conditions are present at the time.

For these reasons, I have made my ailerons big. They are 430mm (17 inches) long, 40mm (1 and a half inches) wide. They start 100mm (4 inches) out from the TRUE centre of the wing.

If you are building shorter ailerons, place them out towards the end of the wing.
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Dec 20, 2005 at 09:13 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Oct 06, 2005, 06:08 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
Aileron Modification – 3 Equipment (for What I Did)

Sharp knife (I inserted a new blade for the project).
Long straight edge (600 mm / 24 inches).
Good quality clear packing tape.
Domestic “Magic” sticky tape (the stuff you write on, that smells a bit odd).
A battery drill.
A heat gun or a hair dryer.
A pair of control horns.
2 lightweight servos. I used Hitec HS55’s because of their weight (9g), torque (1.1kg) and long servo leads (200mm, 8 inches).
2 short (100mm / 4 inch) servo extension leads. Or, if you are running both servos on one channel, a short “Y” lead.
If the leads that come with your servos are short, 2 more extension leads
Rods and clevises (or equivalent) to connect servos to control horns.
A 1 metre (or 36 inch) x 8mm carbon fibre tube.
Some 1mm x 3mm (1/8 inch) x 1 metre (or 36 inch) flat carbon strip – or a sheet of 3mm thick stiff balsa.
Masking tape
Medium CA “superglue”.
Accelerator (also known as “kicker”) for the CA glue to make it set quickly.
3M77 or 3m Multi Purpose spray adhesive – or any other clear contact adhesive (doesn’t need to be spray-on).
Sandpaper.
Screwdrivers.
Ian Pullar is offline Find More Posts by Ian Pullar
Reply With Quote
Old Oct 06, 2005, 06:09 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
Aileron Modification – 4 Flattening The Wings

Usually the ailerons MUST be on a straight section of the wing, and if the ailerons bend in flight, they may jam, even though the Elapor is more forgiving than most materials. Also, a bending wing does not look good and is putting the hinges and servos under pressure.

As I was planning to do some pretty heavy flying, including loading it up with weight on the slope when it was really windy, I went with the “stiffened” option as described below.

Wing straightening can be done with a hair dryer or – if you use it VERY carefully and from a distance, with a heat gun. Don’t let the hot tip of the heat gun lean against something it shouldn’t, like a plane, while you are looking the other way.

HINT - The upturned tips will cause your plane to be thrown around in turbulent conditions when a gust comes in from the side, and they restrict its aerobatic capabilities slightly, however I suggest you gain experience before you flatten the wing tip fully (or almost fully). The plane with flat wings, but still retaining the wingtips as is, remains remarkably stable and forgiving and, with a decent rudder modification, I could almost fly it on rudder only.

Some people have done without stiffening the wings but I have full length ailerons and I wanted a plane that could handle some hard work and would last for years.

The original wing joiner is 8mm fibreglass tube, 500 mm long. My local hobby shop had some 8 mm x 1000mm carbon fibre tube. The fibreglass tube weighed 23 grams, the carbon fibre tube, although twice as long, only weighed 33 grams, so this added only 10 grams to the weight of the plane.

I actually bought a second Easy Star kit, this time an ARF (Almost Ready to Fly) for this project and so was able to remove the wing-joiner cover in the wing and “drill” the hole deeper. Removing the cover gave me a little more control over the drilling process, but it is NOT essential.

I had to push some wire through it to clear the drilling tube regularly. I used the longer carbon fibre tube (1 metre) to finish the 500mm hole in each wing.

HINT - If flattening the tips, it is recommended that you maintain a little washout, ie the trailing edge (rear) of the wing slightly raised, about 2-3mm (1/8 inch). This reduces the likelihood of the outer wing stalling in flight before the inner wing. (If the outer wing stalls first, you can “tip-stall” and the plane will be on its side before you know it, sometimes close to the ground!)

You may need to put tape on the bottom of the wingtips to keep them flat and for stiffness.

HINT - do not put fibreglass tape on the TOP of the wings as, when exposed to the sun for a while, the fibreglass turns to dust.
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Oct 06, 2005 at 08:25 AM.
Reply With Quote
Old Oct 06, 2005, 06:10 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
Aileron Modification – 5 Why I Used Taped Hinges

To maintain the lift of the wing, it is particularly important that the air going over the TOP of the wing is unhindered. If it is upset, it will “let go” and swirl around after the “upset” and not provide lift, aft of the disturbance. This is particularly important if you are flying slowly (as you will with this plane) and if the ailerons comprise a large part of the wing, as mine do.

Putting in hinges at the centre line of the cut would mean a deep “valley” in the top of the wing, which would disturb the airflow well before it reached the trailing edge. Taping it at the top gets over the problem.

I am aware of some comments that this reduces the possible travel of the ailerons, but in practice I did not find this to be a problem in mine. I can increase the travel even further by moving the servo rod along the aileron horn, in closer to the aileron.

I also find making taped hinges easy, cheap, reliable and easily repaired after major incident.
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Oct 06, 2005 at 06:35 AM.
Reply With Quote
Old Oct 06, 2005, 06:11 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
Aileron Modification – 6 Cutting Out And Attaching Ailerons

Make your short cuts (for each of the ends) clean and straight. Later, you will need to shorten the ailerons 2mm (3/32 inch) to give clearance so that they don’t bind at the ends as they move. However, you may wish to shorten them AFTER you tape them, so you are accurate.

To ensure the aileron has rigidity, I glued a length of 3mm (1/8 inch) x 1mm carbon fibre strip along the top of the front edge of the aileron, using the CA and kicker (accelerator).

*If I didn’t have a carbon fibre strip, I would have faced the aileron with 3mm (1/8 inch) thick balsa.

**If I was not going to put a long tube into the wing, I would have also stiffened the rear face of the wing also, using more 3mm stiff balsa.

(*The above would also require cutting *3mm or **6mm (1/4 inch) slice off the width of the aileron (to account for the additional *3mm or 3+3=**6mm added, so the aileron didn’t stick out that far further than the wing.)

www.depronusa.com site says they have carbon fibre strips that would suit. (But their tubes are too small to replace the 8mm fibreglass wing joiner.)

Put clear contact adhesive on the top, where you intend to put the tape. (Test adhesive first on your triangle off-cut to ensure it doesn’t eat foam. A few will.) If using spray adhesive, spray a little into a tin or a jar lid then paint it on.
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Nov 03, 2008 at 04:18 AM.
Reply With Quote
Old Oct 06, 2005, 06:12 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
Aileron Modification – 7 Attaching The Aileron Servo.

Servo hole is cut 200mm out from (real) centre of wing, with enough servo lead to play with to push into the short extension lead that comes from the receiver and sticks out the hole where the servo on the side of the plane is.

Ensure servo hole is in FRONT of the wing joiner. (Don’t install it and find out you’ve just plugged up the wing joiner hole!) Cut the hole with a knife and keep slicing within the boundaries of the hole and scrape out the Elapor until you have a neat hole for the servos to fit tightly into.

YOU must (must must) “centre” the servo arm on your servo before installing it. To do this, plug it into your receiver, turn on transmitter, attach power to receiver and turn it all on. Ensure controls AND TRIMS (including electronic trims) are CENTRED. Note position of arm. Turn it all off, remove and replace servo arm so that it is at right angles. Before replacing screw, turn it all back on again and re-test it. Check it again to be sure.

Of course left and right servos need to be set mirror image of each other!

HINT – some servos have an odd number of splines (ridges) on the shaft. So if you put a double ended servo arm on the shaft one way, it will have a slightly different offset than if it were on the other way (ie attempting to put it on at 180 degrees). Use this to your advantage to get your servo arms centred as much as possible before cutting off the unwanted servo arm end.

NEVER SCREW IN SERVO ARM WHILE SERVO IS “LIVE” AS YOU MAY BE PUSHING AGAINST THE WORKING SERVO. I did – and wrecked a brand new servo. (Sob.)

If you don’t have a computer radio that will allow you to dial in differential, but you think you would like differential, then after centreing the servo, mount the servo arm so that it is pointing about 20 degrees forward. Remember still that left and right servos need to be set mirror image of each other!

I simply used good quality clear backing tape to hold the servo in. You could use contact adhesive but you may need to roughen the smooth surface of the servo first, or put a layer of masking tape on it.

If you insist on using CA to glue the servo in, first wrap the servo in a layer of masking tape, so the servo is usable if later withdrawn for another model. Thin CA may spread into the servo mechanicals and jam it. Thick or Medium have less risk. If in a hurry, spray CA accelerator (also called kicker) into hole and wait for it to dry. Then put thick CA onto servo (AWAY from mechanicals) then place servo into hole. Or, put the kicker on the servo and the CA in the hole.

I connected the servo horn to aileron horn with a control rod with a clevis on one end and a z-bend on the other. If you don’t have a z-bender and don’t know how to make z-bends easily, go to:
http://www.rcgroups.com/forums/showt...29#post4321129
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Oct 07, 2005 at 05:58 AM.
Reply With Quote
Old Oct 06, 2005, 06:12 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
AILERON MODIFICATION – 8 Wiring - Cost and Weight - Other Modifications

The servo leads are tucked into the gap between the FRONT of the wing joiner cover and the wing, and lead back towards the wing join. In the plane, I have added 100mm (4 inch) servo extension leads from the receiver, coming out through the holes where the elevator and rudder servos are.

HINT - I made sure that both had the yellow lead wires towards the to the front of the plane, on each side, so I never got confused plugging them in.

Cost and Weight

Servos, tape and rod cost me about Australian $70 all up. Total weight addition, about 50 grams.

Other Modifications – see pictures below
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Oct 07, 2005 at 05:51 AM.
Reply With Quote
Old Oct 06, 2005, 06:13 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
AILERON MODIFICATION – 9 Rates / Mixing / Differential / Flap-Spoiler Deflection / Ex

Dual Rates
I don’t generally use dual rates as I like my plane to react the same in any emergency at any time, regardless of switch settings. However for my trainees, I halve the rates to about 6 mm (1/4 inch) up and 6mm down aileron.

Some flyers prefer dual rates however I recommend the rates not be TOO different from each other or big surprises (disappointments!) can occur when things happen fast close to the ground.

Mixing – Ailerons to Rudder
It is possible to mix ailerons to rudder, so applying aileron also applies a little rudder, and some flyers prefer this. However I found this plane is small enough not to require it and I would have to switch it out to do rolls. So I left it out. If I want rudder in the turn it is right there when required, on my other control stick.

Mixing – Throttle to Elevator
Some planes, because insufficient down thrust built into the motor mounting, require the mixing of throttle to elevator so that full power give a little down elevator. Without it, with full power these planes will continually nose-up and it is necessary to “ride” the down elevator to compensate. The Easy Star didn’t seem to have this problem and so I did not need to add this mixing. In fact, with my powerful brushless motor, when I accelerate fast, the nose is temporarily pushed DOWN before the plane builds up speed and the nose rises.

Differential
Because a down aileron can create more drag than an up aileron, turning the plane with the ailerons can sometimes cause the plane to yaw (ie turn its body) the opposite way that the turn is intended. Eg, to turn left. left aileron goes up, right aileron goes down. But right aileron (down) creates more drag, to the plane swings to the right before the plane starts to bank to the left. This is called adverse yaw.

For this reason, sometimes people put in differential, which gives more up aileron than down aileron. I tried it however this plane flies fine and also rolls better and flies inverted better without it, so I took it out.


Flap/Spoiler deflection (Flapperons vs Spoilerons)

I had much optimism about being able to use down flaps, called flapperons (ie both ailerons down), but was disappointed with them.

I found spoilerons to be the better option, ie both ailerons UP. It didn’t stop the plane as effectively as spoilers on a glider do, but it had less lift and came down at a greater rate without forward pace increasing.

But the big thing about being able to adjust flaps in flight is being able to change from floaty to fast.

My radio provides the ability to use a lever at the side to give infinite adjustment between high an low flaps, however I simply ended up using the 3 way switch, to dial in (a) full spoilerons for some landings, (b) fast mode (with the underside of the aileron being in line with the rest of the bottom of the wing, ie no under-camber) and (c) Floaty mode, being the wing in its original under-cambered position.

For general flying, I found there was no gain by having access to additional settings other than (b) or (c), so I no longer use the infinite adjustment that is available to me.

If your radio doesn’t allow this, don’t despair, because, even with a “Y” lead, you can adjust your wing’s camber before you leave the ground, by turning in or out some turns on your clevises, allowing you to fly in a manner which matches the conditions and your mood.

On some planes, different flap settings require a simultaneous alteration to elevator. The Easy Star didn’t seem to need this.

Exponential

Exponential is a feature of some computer radios, it allows a “curved” control surface response, so that you can use a fair amount of movement in the middle of the stick and only get a little control surface movement, but when you use move the stick to the outside edges, the control surface moves a lot. This means that you get the advantages of stability combined with the ability to make rapid manoeuvres (by moving the sticks all the way out) when you wish to. I use this on all control surfaces, at about 20%. I suggest you start conservatively and DON’T just believe the manual on this, LOOK at your plane and get to understand the impact that this change has.

On some radios, the arrangement as I have described above is described as positive exponential, on others it is described as negative exponential. Experiment to find out what yours does. Get it wrong and you will probably crash.
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; May 09, 2006 at 10:46 PM.
Reply With Quote
Old Oct 06, 2005, 06:15 AM
Registered User
Melbourne
Joined Jun 2002
272 Posts
Aileron Modification – 10 Outcomes / Flying Characteristics - 4 Planes In One

Outcomes / Flying characteristics

I’m amazed at how well it goes and its performance range and manoeuvrability. Rolls, loops, inverted, fast passes – or gentle flying or searching for thermals - or, into a stiff breeze, can be slowed to almost standing still. Great size.

The only thing is that in fast rolls, you can see that it takes a while for the tail feathers to catch up, ie they start rolling a little later and I see the fuselage twist. This doesn’t affect the enjoyment it provides or reduce its performance, but it does look a bit funny. And it is pulling apart the double sided tape that is holding the rear together and I will have to put some light tape on the outside, or glue it.

4 Planes In One

I have this plane saved in my computer radio as separate models.

1 - For my own flying, I fly with ailerons on separate channels so as to be able to fly with spoilerons, and with a lot of travel.

2 - Because I sometimes train with a buddy box (ie I have a master transmitter and my trainee has a slave transmitter - which only allows the buddying of 4 channels), I need to run with a “Y” lead. My left aileron channel extension lead is actually a “Y” lead, so for training I remove the right aileron plug from the extension lead of the extra channel and plug it into the “Y” lead for training, I also reduce the travel for them.

3 - I have a third model saved in memory which is for when I am flying with my non-aileron wing, which I sometimes do for beginners. On this, I have aileron to rudder mixing (because there are no ailerons on this wing) so that my trainees can fly a very docile and forgiving model using the normal steering stick, but it now controls the rudder.

4 - The forth option, is when I add BOTH wings so as to make a biplane – just for the fun of it. For this I use the settings for the first option.

I’m wondering how easy it would be to convert one to a canard…. ?

I like this plane. Cheers – IP
Ian Pullar is offline Find More Posts by Ian Pullar
Last edited by Ian Pullar; Oct 06, 2005 at 08:37 AM.
Reply With Quote
Old Oct 06, 2005, 06:33 AM
Registered User
AeroNut45's Avatar
Australia, VIC, Keysborough
Joined Jun 2004
2,036 Posts
Where do you get the time to write all this, never mind doing the actual alterations? I am getting exausted just reading it.
AeroNut45
AeroNut45 is online now Find More Posts by AeroNut45
Reply With Quote
Old Oct 07, 2005, 03:02 PM
"SARGE"
sargentw's Avatar
Fairfax Station, (Northern) Virginia
Joined Jun 2003
3,150 Posts
3m Packing tape amd 3m77 spray

To help clear up confusion on packing tape, etc. Here is a picture of the 3m extreme packing tape and the 3m-77 spray adhesive that helps it stick to elaptor and epp foam. There is a roll of duct which I would avoid using because it's not as strong and can make a gooey mess. Don't use 3m77 on stryrofoam or it will melt the foam. Always test the spray on a small piece of foam if you are not sure.

The other pictures are where I've applied the spray and packing tape. Only use strapping tape where and when you need it. It will weigh your plane down. The 3m77 spray is optional, but using it will give you superior and lasting results.
sargentw is offline Find More Posts by sargentw
Last edited by sargentw; Oct 07, 2005 at 03:27 PM.
Reply With Quote
Old Oct 10, 2005, 10:22 PM
Registered User
Joined Mar 2004
5,237 Posts
Use water based contact cement on Styrp Sarg. Sticks like.. er... glue.

BTW - have you tried the new 3M CLEAR duct tape? Just bought a roll last week - no time to try yet.
rutat is offline Find More Posts by rutat
Reply With Quote
Old Oct 11, 2005, 07:55 PM
"SARGE"
sargentw's Avatar
Fairfax Station, (Northern) Virginia
Joined Jun 2003
3,150 Posts
rutat,

I used 5 min epoxy on styrofoam (Graupner Terry). I don't do styrofoam planes anymore.

I'm open to trying any new tape. However, if you can rip clear duct tape like regular criss crossed duct tape with your fingers it's not going to be the first choice on my planes. The 3M exterme packing tape is way stronger than duct tape. In addition, even with the crisscrossed pattern of 3m extreme tape the planes color under the tape shows through at a distance.

All the flying wing kits I've seen use reinforced packing tape, not duct tape. My first Wing Kit Combat Wings XE2 was delivered with a roll of 3m extreme tape and I've stuck with it ever since.

If clear hinge tape is to be used they make special hinge tape that seems more like plastic than clear packing tape. It's pretty tough too.

Sarge
sargentw is offline Find More Posts by sargentw
Reply With Quote
Old Oct 11, 2005, 08:37 PM
Registered User
Joined Mar 2004
5,237 Posts
Sarg, that "special" hinge tape (like DuBros) - is really 3M Blenderm. As for clear duct tape, I have yet to try it but for HD use, 3M Extreme is unbeatable. I can see a use for clear duct tape thugh - like over coloured surfaces (anti-skid).
rutat is offline Find More Posts by rutat
Reply With Quote
Old Oct 11, 2005, 08:50 PM
"SARGE"
sargentw's Avatar
Fairfax Station, (Northern) Virginia
Joined Jun 2003
3,150 Posts
Roger that! and thanks, I wasn't sure who made the hinge tape.

Sarge
sargentw is offline Find More Posts by sargentw
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Sig Four Star 40 ARF Engine recommendations and Building Tips Daverp Beginner Training Area (Fuel) 24 Jul 12, 2009 02:38 PM
Discussion Finished building my easy star :) lee2005 Foamies (Kits) 2 Mar 02, 2007 05:10 PM
Simple 400 Building Tips? 99esq High Performance 4 Sep 10, 2001 07:07 PM
Wattage F-22 Building Tips / Pictures rcfanatic Foamies (Kits) 9 Sep 08, 2001 02:25 PM
IFO Mark3: Any last minute building tips ? volt flyer Parkflyers 13 Jun 21, 2001 03:33 PM