Oratex Fabric Covering Revisited

[jrevens]

One other minor point related to HighWing's previous post - when using heat to activate the adhesive, you actually do "smooth" the edges. The more you iron & apply pressure, the smoother it gets. Any little "blobs" underneath are softened & smoothed. Same thing with minor wrinkles, etc. after being heated to activate it, the glue cross-links & develops greater strength over a period of days, & then requires a much higher temperature to melt. It is a stronger bond than the PolyFiber glue - see the latest Kitplanes article.
Also, some of the dust lines seen by Lowell may have been due to adhesive applied to the fabric too close to the edge of the tape. The glue is clear, but looks a little different/darker when heated. The tapes come with glue pre-applied, & you apply a thin layer to the underlying fabric, keeping it a short distance from the edges. The glue is not at all visible at the edges if done properly. The glue on the tapes alone is adequate according to what I've been told, but applying it to the fabric adds additional "insurance".

[jrevens]

As promised, here are some pictures of my initial foray into Oratex land. I haven't had much time to work on it, but I started with the rudder (which is now complete & ready for flight), and am now working on the elevator. I'm getting more comfortable with the process, & I like the look.

[LSaupe]

Great pics. I am amazed at how well the painted parts match the material.

Please keep us posted on how the wings progress. Will you be doing any rib stitching?

[rocketman2tm]

I am looking at using this fabric as well. I am very curious as to whether you reinforced the trailing edge of the wing to ensure it does not warp. The instructions for Oratex say that it should not ruin structures like that but I wonder if I should just reinforce it anyway. I'm not to the point of loosing sleep over it, but give it another couple of months and I might be.

[jrevens]

I did reinforce the trailing edge with 3/8" Al tube. Oratex does shrink to the proper tautness, but it doesn't continue to tighten to the point of structural deformation, unless the structure is very thin or weak. You can apply heat right up to just below 482 deg. F., at which point it melts. I just felt good about strengthening the trailing edge.

Here are a few more picture of working on the rudder...

[jrevens]

Great pics. I am amazed at how well the painted parts match the material.

Please keep us posted on how the wings progress. Will you be doing any rib stitching?

I will lace the wing ribs.

[Danzer1]

John,

That looks very good! It appears in your photos that the Oratex fabric and tape has a much smoother weave than the others. Is that just my perception of the photos or is it smoother in your opinion also?

Keep up the fine work - you are inspiring!

Greg

[jrevens]

John,

... It appears in your photos that the Oratex fabric and tape has a much smoother weave than the others. Is that just my perception of the photos or is it smoother in your opinion also?...

Greg

Hi Greg,

I'm not real sure about the weave comparison. Oratex definitely has a "texture" that you don't have with a conventionally covered/painted surface. It is a very fine weave, & visible on the finished surface. The 600 (the "light" material) is different than the 6000. It has an even finer weave. I chose to use 600 finish tapes (they are available made of 6000 material also). The 600 stretches & conforms around curves a little easier than the heavier stuff. You can also get pinked or straight edge. Because of the different texture, the lighter tapes have a little different look even though they are the same color - perhaps because of reflectivity. I'm sure you can see it in the pictures. I don't mind that.

Thank you for the kind words.

[Dave S]

Hi John,

Your covering work really looks nice.....What type of paint do you use with this system?

Dave S

[Clark in AZ]

I am new to the covering scene, either Polyfiber or Oratex. I took an EAA Polyfiber workshop but then decided to cover my SuperSTOL with Oratex. Anyway, I've been helping a friend cover his Kitfox with silver Oratex and we did not achieve the results in your pics. You did an incredible job covering the rudder and elevator! It shows me it can be done correctly. I wish you would share some of your techniques for getting the smooth edges on the top of the rudder and the tight curves of the elevator? How did you cut/lap the fabric and tapes and get them to lay down so smooth? Thanks for sharing!

Again, excellent job!

Clark

As promised, here are some pictures of my initial foray into Oratex land. I haven't had much time to work on it, but I started with the rudder (which is now complete & ready for flight), and am now working on the elevator. I'm getting more comfortable with the process, & I like the look.