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Old Feb 14, 2013, 10:32 PM
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Elizabeth South Australia 5113
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The steering servo is mounted on a Glass / Carbon / Ply plate that is just behind the nose wheel with a loop in the wire to act as a servo saver. I found that the "Tower Pro" 90 S suitable.
I bent up a wire U/C out of 3 mm music wire mounting through the frame with fuel tubing holding it in place . After a heavy landing ,the wire will be pushed out of place , but easy to reset.
This model will need two 10 k/l MG servos for the wing control. I have found that the Blue Bird 620 mg is good for this. It requires long arms allowing for 40 mm pivot points.
I attached the servos using hot glue and nylon ties. This set up holds the servo in place and it will take a little abuse....but if it has a heavy hit...simply allows the servo to move ...without breaking any thing.......apply heat to the glue and it's fixed.
I used 1/16 balsa with 2 oz glass cloth on each side as the base plate. Very strong and light. I am sure there are many other things that can be used.
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Old Feb 14, 2013, 11:23 PM
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Elizabeth South Australia 5113
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The wing on this model needs to move on a central pivot that allows it to pitch and roll.
I used a carbon arrow shaft with four lengths of glass rod epoxied internally for the main central shaft with a short length of ally tube for added strength .On the first model that I made, I used bearings on the pivot point ,but decided that in my opinion that it was not necessary for my second model.
The pivot is simply an arrow shaft with a lenfth of square 10 mm OD tube that has an 8 mm ID that simply allows the movement. This is very" low teck" that works.
Also mounted on this central shaft is a mounting block for the " A " frame and a pivot arm that is connected to the servos via long push rods.
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Old Feb 15, 2013, 07:11 AM
scale microlights
mark675's Avatar
midlands uk
Joined Sep 2004
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nicely done Chris!
this is actually the first time ive seen the details of your trike!
its very simple and works well, this is great information for the people without workshops and machines,

i always over engineer things

great stuff! pics of the rest of the wing next mate?
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Old Feb 15, 2013, 04:56 PM
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Elizabeth South Australia 5113
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Thanks Mark......that's me ...simple
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Old Feb 15, 2013, 05:31 PM
scale microlights
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midlands uk
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Lmao
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Old Feb 15, 2013, 11:35 PM
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Elizabeth South Australia 5113
Joined Nov 2005
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Now the wing.
This is possibly the most difficult part of the build . All the work on the trike has been just a variation of building fixed wing and autogyro type builds.
Fortunately I took many pics of this build and hopefully they may help to explain what I may have difficulty to put into words. {some of these pics are a little fuzzy}
On the first wing I built I used a combination of carbon tubes with solid carbon rod inners.this worked OK.
But for this model I managed to get my hands on a cheep kite .The cloth sail is not suitable for this model so I got the wing material from a kite shop on ebay. It is very cheep with a great rang of colours. The glass rods are about 4.77 mm and just the right amount of flex.
I drew up the wing plan directly on my work bench and this made things pretty easy to hold in place when I needed to put a little tension on it.
The wing needs to be a little on the "flexy side " because that what they do in full size.
You will have seen Marks beautiful machined works of art. I am a little embarrassed to show my simple joiners.
At the joint of the central shaft and the two L/E rods, I simply inserted a length of 1.5 mm wire into each end of the rod ,through the ally tube.The tube ends are reinforced with a short length of metal tube [ old antenna and C/A in position.]
The other joints are just the same with wire inserted into the rods and then secured with carbon rovings/glass rovings /strong thread to the correct position.
There is a curved rod {this is not in Marks plan} that is attached to the central wing pivot arm via saddles.
Make sure to remove the gloss from the glass rod before flooding the thread with thin C/A.
The wing "ribs" were made using a combination of 1.5 mm galvanized garden wire
[easy to bend} inner nyrods / bamboo steak skewers. I drilled shallow pilot holes in the L/E
rod and secured the wire in place with thread and C/A . {yes it does stay in place}.
The wing is made in one piece. and hope fully it will stay tat way.
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Old Feb 16, 2013, 04:31 AM
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Ricardo1500's Avatar
Wolverhampton, England
Joined Jun 2010
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Chris

Great build log with some proper modellers lateral thinking
Me thinks its time to clear the bench!!

Cheers
Rich
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Old Feb 16, 2013, 04:12 PM
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mark675's Avatar
midlands uk
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Go for it Rich

good stuff chris! some nice ideas and clear pics

regards,mark
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Old Feb 16, 2013, 04:29 PM
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Elizabeth South Australia 5113
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Thanks Guys
It's the lateral thinking that stops me from falling over all the time.
I do hope this is making sense to you as it's not always easy to explain how things are done. That's why I have put up a lot of pic's to try to clarify the build .
Chris............
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Old Feb 17, 2013, 12:34 AM
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Elizabeth South Australia 5113
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The Wing Covering..........It's a lot of fun........But if I can do it....so can you....
The kite material that I purchased on Ebay was unfortunately not long enough to cover the wing....so I had to cut some of the width and sew it onto both tips. At this stage the wing should be on a flat surface with all ribs attached. One final centre rib must be made from apiece of 1.5 mm music wire and bent to a nice wing section .
It must be the full length of the center of the wing plus a right angle bend at the tip going through a vertical hole in the front of the ally tube for about 40 mm. I used the wire to locate into the bench top to help keep the wing in place during assembly. [you had better read that again].
This wire rib runs through a curved pocket that has been sewn in to the centre if the wing material. I simply drew a line on the material that I thought was the correct shape for the wing section and sewed two parallel rows to make a pocket for the wire rib..
I found I had to put the material in warm water and hang out to dry to remove the packing fold marks and then a light iron.[ I did not do this on my first wing and the folds have never come out ].
Now the real fun part
Placing the centre wire rib in the wing pocket and pushing the right angle bent through the ally tube into the flat surface and evenly spread the material out over the ribs and frame.
At this stage it may become clear that some of the ribs need to be bent a little to a correct shape. The short carbon / glass rib at the tip should be angled up at about 20 deg [ these ribs helps to keep T/E up before the wind lifts them ]
I put weights on the wing material at this stage and left it a few hours to spread out . I needed to go and see my friend "Jack Daniels " for some advise on the build.
The next day ,it looked a lot better , so I started to attach the material to the L/E with craft glue. Now this is that glue that is sold in craft shops for making lamp shades etc. It is a clear rubbery type of glue that can be rolled into a ball in your hands with out making a mess.
Run a good Bede on the L/E and evenly roll the material over the rods. I found that it was best to keep the material beyond the T/E draped over the bench to maintain even tension.
I went to see Jack again...........You have to give the glue time to cure.....
When completely dry ...turn over.... lay flat...and secure the ribs in place with reinforced tape. I used the 20 mm width.. I think Mark used wider .
The material can now be cut at the T/E and fold under at the L/E and all taped down.
A small loop needs to be attached to the L/E at the spar joint for a flying line A line can be attached to the centre of the "floating spar" and tied off at the end of the central spar with some tension. This action helps keep the entire wing tight.
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Old Feb 17, 2013, 07:04 AM
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Australia, VIC, Craigieburn
Joined Jul 2012
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top description of the build Chris. i think you have put it down with nothing to chance.
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Old Feb 17, 2013, 08:38 PM
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Elizabeth South Australia 5113
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Now here are a few pics that I should of shown previously of how the wing was secured prior to applying the tape to the ribs and also showing the tip spar in position.
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Old Feb 17, 2013, 10:16 PM
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Elizabeth South Australia 5113
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The " A " frame was made from arrow shafts, carbon rod and Ally tube .
The assembly is bolted to the holder on the central shaft and rigidly attached to the control arm and nose loop by strong cord.
I have two X 50 mtr lengths of kite string that came in the cheap kite that I started with that is very good for this purpose.
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Old Feb 18, 2013, 10:35 PM
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Elizabeth South Australia 5113
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The servos are connected to the control arm via 3 mm carbon rods with ball joints at the top.
Metal clevises with retaining clips are used at the bottom. Long servo arms are required. I found 40 mm was needed where as I believe that Mark used 25 mm. I went with the 25 mm to start but found it was not enough for my set up.
A lot of my first flights found the model breaking ground and then rolling on its back spearing the point of the wing into the turf.
This went on for a time until I increased the arm length and all was good.
The TX has to be put in the DELTA setting for this model { similar to a lot of autogyros}
When the model is sitting on the ground it is needed to be able to touch both wing tips on the ground going from full left aileron to full right aileron. Now that may seem like a lot of movement, but it needs it.
It must be remembered that this is a true weight shift control system as per a full size microlight.
Looking at any videos of full size machines will clearly show the pilot pulling and pushing the bar to the side and front to move his body weight under the wing.
The settings are not difficult set up in flight as it is a matter of a balance of throttle and "elevaror".
As the thrust line is a lot lower than the wing, it is found that application of power will make the nose lift.
I did loop my first model several times just trying to trim the beast. So gentle application of power is the way to go. I found that applying power and just doing small "hops" was a good way to get the trims sorted out.
When the model is trimmed out it will just about lift in its own good time when it gets up to flying speed with only just a touch of elevator.
Landings require a burst of power at the last moment to help the rear wheels touch first.
I made many nose wheel repairs before I got it sorted.

I think that the biggest difference between Marks set up and mine is that he has found that his model flies better using servo savers [ springs } on the controls. I have not found the need for the springs ,so it's very hard to tell if either model flies better than the other, but the important thing is that we are both happy with the way they fly.
.
The hang angle of the trike is not critical ,but I try to get it as level possible by the position of the battery.
A starting setting for this model is to have the trike base level and the wing at approx 6-8 + .This model will not need any down elevator setting because unlike a fixed wing model the idea is to try to keep it reasonable level, although loops are possible.
The following pics are of my first model showing the control/servo settings, but they are very similar to "pinky".
I am also showing some pic's of Marks fittings to let people see the way it should have been done.
To any one who is not aware there are videos of Marks and my models on the other Microlight listing.
I think that it is just about my ramblings for now folks.
Happy Landings
Chris..........
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Old Feb 21, 2013, 02:41 AM
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Elizabeth South Australia 5113
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The Pink Microlight. (4 min 20 sec)

This is about the 6 th flight after some trim adjustments.
One thing I mast say is that I would never use this colour again. Although it is pretty easy to see in the sky ,I found that it was a pain to work with as it was playing tricks with my eyes.
Happy Landings
Chris........
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