Poor man's Sonex trim...

I have always liked Sonex trim system but you just can't buy everything you like just because it would be nice on the plane (my wife says)... 

...but I'm allowed to build anything I like as long as I'm using scrap material...

Oratex 6000 used for exposed areas

While using Oratex UL600 for all other parts I used Oratex 6000 for the landing gear for extra protection on this particularly exposed area...

I used extruded polystyrene foam for the trailing edges, it is very stiff, easy to shape and it weighs nothing...

Aluminium tape give a good strength to the edge where the foam is thin.

While Oratex UL600 is very strong the 6000 feels almost destructible. This might be overkill but the landing gear take a lot of beating - particularly when passengers get in and out...

There is a video on YouTube where gravel is shot on Oratex 6000 with a slingshot at -25 C (-13F)... and another where they beat it with a hammer...  

Covering has started

The 1.5 minutes in the film represent a full hour
I agree, watching this film is like watching paint dry (but it only lasts 1.5 minutes while paint take much longer..!). It is not very exciting, nor is it particularly instructive as you don’t really see the details. But there is a message in the film…
Using Oratex provide a lot of flexibility. I had already, actually a few days ago, prepared the fuselage and the fabric by applying the glue. So when I decided to skip lunch and work on the plane instead for one hour I could easily do that and know that I could stop on top of the hour, roll the plane back in the barn and with clean hands and without having to change go back to work. I can pick up exactly where I left at a later time (after dinner, lunch tomorrow or this weekend)... 

Finally read for covering…

The preparation of the fuselage has been delayed by work obligations but I’m now ready to start the covering work.

All “difficult to cover” areas have been prepared as well as openings for cables, jettison/purge and break tubes. 

An additional inspection trap is prepared for above the tail wheel for easy change of tail springs and cleaning out whatever nuts and bolts accumulate in the end of the tail...

I hope I have prepared and done all that is required before covering the fuselage. 

Using Oratex UL600

Using Oratex is clean and, as my office is big and my workshop is small and cold, I decided to work in my office for the smaller parts (actually everything except the fuselage).
Applying Oratex is very simple and the result is easily very good. While Oratex is attaching very well to the structure the best is when Oratex is glued to Oratex with the hot-melt. One way to increase the surface of Oratex against Oratex is to use edge tape.  
Where I run into difficulties was when I wanted to apply the edge tape to a surface with rounded corners (like the elevator). While Oratex expand a little under heat and tension, and retracts under more heat, there is a obviously a limit in the relation between corner radius and edge tape width. To get around this (after an initial failure...), without reducing the width of the edge tape, I cut a "waist" in the edge tape around the corners and before cluing it I applied a curved piece of fabric, with the same width as the edge tape, to the corner that would then be partially covered by the edge tape.    Agree, not my most exciting scenario...

My first Oratex experience

The smallest part to cover, other than the landing gear, is the rudder so I started with that. Both the frame and the fabric (where it touches the frame) need to be prepared by applying the hot-melt glue. I'm normally very sensitive to smells but when painting the frame and fabric I couldn't smell anything. I had to put my nose in the bucket to feel a slight sweet smell of "children glue". 

The hot-melt attaches easily to the fabric but I had to lightly sand the frame as the epoxy powder paint is very glossy. I let it dry over night (small surfaces can be dried rapidly with a hot air gun set to cold). The synthetic brush is easily cleaned in water.

I clamped the fabric to the frame, making sure it was positioned so that the hot-melt on the fabric was correctly aligned to the frame. While attaching it with the iron at strategic points, I did apply some moderate tension. Using the hot air gun when covering any rounded surfaces helps to soften the fabric and make it fit easily before using the iron to activate the hot-melt. 

While the rudder is the smallest part, it has a a long rounded edge and I had decided to put a pinked edge tape on it... Not a beginners task but you have to start somewhere. There is video on YouTube where this is done and I used a similar method. The edge tape already has hot-melt on it from the factory so it is very easy to work with. The result was not perfect but absolutely satisfying.

Final tension is applied with the iron... and then it is finished as no paint or other surface treatment is required!

I will try to do a time laps video when covering the elevator. 

Unboxing

All the Oratex UL600 needed (except for the wings), some Oratex 6000 for the landing gear, pinked edge tape, magic hot-melt glue, iron and hot air gun with digital temperature settings and some other things that will come in handy arrived in a big box this morning. 

What you see in the picture is all what is need; no solvents, no dope, no paint... (I know, I'm repeating myself...)

My apologize to anyone mislead by title and disappointed by not finding in-depth descriptions of the characteristic smell of the cardboard box and the quality of the packing material...

What is Oratex?

First of all, I’m not sponsored by Lanitz Aviation – or anyone else... Lanitz Aviation kindly offers me free freight on my orders but are not requesting anything in return. What I’m doing here, on my blog, is sharing my personal experience with this product just like I’m doing for the Simonini engine. 

Oracover used for model aircrafts

Oratex is an aircraft fabric covering system, produced by Lanitz Aviation, similar to what has been used for covering model aircrafts for a long time. It looks like a fabric textured colored plastic film, it is ironed-on using a water based heat activated clue and need no further treatment or painting.

In reality is an extremely strong (high tech) coated polyester fabric developed for general aviation. Oratex UL600 is lighter than traditional aircraft covering systems 90 to 120 g/m² all inclusive (depending on color) and the difference might be several kg even for a smaller aircraft. I assume that this is one of the reasons why the Solar Impulse design team chose Oratex fabric as the cover material...    

No dope, no paint, no sanding, no harmful chemical exposure, no smell and no fire hazard. I will be able to do the tail plane and rudders in my office and no problems to turn on the heater and close the doors when doing the fuselage and the wings in my workshop!

No paint that will peel off, no cracks, not flammable and easy to repair even in the field. 

For more information: The North American distributor of Oratex has a very informative website where you can find more information and some videos. Try also Lanitz Aviation's website and searching Oratex on YouTube .

The Oratex Adventure has started

As planned, I got the fuselage and all metal parts sand blasted and epoxy powder coated just before Christmas. It is amazing, it looks and feels like factory new...

It is time to start the "Oratex Adventure" and I have now ordered all UL600 needed to cover the fuselage, tail plane and rudders. Once that is done I will do the wings... to be followed... 

If God had intended us to fly, he would have given us more money...

I know you have all been there... trying to avoiding to say that what you are looking for is to be used in an airplane - just to save money, or rather, not to be ripped off...

This was the original seat in my Avid Flyer. There is nothing fancy about it, light weight, simple and "so and so" comfortable. But apparently it was very tasty to some rodent that really liked the stuffing... 
So I took it to an old style shoemaker near the airfield who I knew made seats for old cars and bikes. Really nice a cool guy so when he asked I told him it was for an ultra light aircraft (and not a private Lear Jet). We looked at different materials and he told me that leather (that was what I wanted) would be expensive and suggested some synthetic alternatives. So how much would it cost... Well he said, while he got euro symbols in the eyes, about 1.000-1.200 euros depending on the material... No point in asking for the price in leather...
And believe me, he was seriously thinking I would pay that kind of money. Where do they come from? Who made them think people who fly have money left?
It was too cold to work on the plane anyway so I bought a big piece of leather for 50 euros, took my old hand cranked Singer sewing machine and, with the seats from my long gone MGB in mind, I did the work myself. It took me a few hours and while the result is not "pro" it is good enough for me - particularly for thousand euro less - and it will look better when "worn in"!