Oratex is like Yoga Pants

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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

TD1
I have put my the test piece thru terrible abuse, many times and it always shrinks back to new.

Thumb nail as hard as I could, hammer very hard but not as hard as I could, etc.

So I took my folded pocket knife with the end sticking out of the bottom of my fist about an inch, and hammered the center of the fabric panel (H stabilizer), hard. the first blow left a dent, the second to the same spot left the hole in the picture.

Simulating landing in small brush and dropping the tail on a stick.

I was trying to make a puncture hole. It took 2 shots to break through. I would not EVER hit conventional fabric with a hammer, or push my thumbnail into it - too easy to puncture.

Even when I did break through it resisted the tear. Oratex is so much tougher than conventional fabric that it should not be compared equally.
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SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BucF16
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Re: Oratex is like Yoga Pants

Post by BucF16 »

Hey Shawn, hope you were far enough South to avoid any damage!
Best Bruce
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
Builder web site:
http://www.bruceshighlander.blogspot.com
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

All good - says my wife
I am on the North Slope
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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Re: Oratex is like Yoga Pants

Post by BDA »

Thought I would pass along some things that made it easier when riveting wing fabric.

You want to NOT iron the fabric to the ribs until AFTER you shrink the fabric tight.

After you do final shrink and iron and rub the fabric into the glue on the ribs, then start on rivets.

So after the fabric is down you can punch holes for the rivets. I used an oldrivet stem in a pair of visegrips to poke holes where you have predrilled for the rivets

- THE RIBS MUST BE PRE DRILLED BEFORE FABRIC - AND AFTER GLUE.

I drilled every other hole starting with the first hole from leading edge, then every other hole works out to 3” between holes.

BUT it can be hard to find the holes, and you dont want to poke holes in the wrong place!!
So use your thumbnail to scratch the hole outline in the fabric - the first picture shows how hard they are to see, the second is after thumbnail.

After poking holes, you have to heat and seal the hole, so I use a Weller battery solder iron from Hardware store to melt hole and enlarge, followed immediately by a rivet - before it cools - so that the rivet will mash the melted edge down.

Back to gluing to the rib, the shrinking dips in the ribs will cause the fabric to have depressions if you push it down into those - so be careful to rub up to the edge but not down into those, helps to lay the felt blade down flat on the rib
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SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

You might have noticed in my pictures that I am not using the Stienel heat gun that Lars suggests.
I paid 65$ for a Wagoner digital heat gun at home depot and it has worked very well.
But
Lars has given me a ration of crap over it and every problem that I have had is blamed on the “crappy” heat gun.
SO
My buddy bought the Stienel for his project, had same problems I did,
So I borrowed it to finish my wings, and see if there was a real difference.

First impressions - I like the Wagoner better.
But I may be biased because I have used it more - so I will break it down.

Stienel gun is MUCH quieter - about half the noise
The temp control is easier to use with the hand u hold the gun with - but - the buttons are on the back edge so every time I put the gun down the temp changed - almost caused expensive mistake a couple times.
Fan control is a little more intuitive, only 3 levels, second level makes it easier at the ends of the tapes.

Wagoner gun is noisey, but not bad enough for ear plugs
Buttons are protected - never change on me
It has a memory feature that goes back to the last temp setting if you dont unplug
Fan is more powerful.
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

The temperatures on both heat guns seem to be working the same - I use 360* F to stick tapes down with fan on 2 with Stienel gun and 4 or 5 with wagoner gun, then 420 to set the glue.
These temps depend on what is underneath - if just fabric underneath 420 is enough to shrink the tape even after it is stuck down if you dont keep moving. But if there is metal underneath 420 is barely enough and you have to go slow to make the glue set.
I can see where someone could get all the tapes down and think they were good, but then have some or all lift.
The glue on the tapes is different then the brush on glue in that the temp range to set the glue is narow and not far from the temp that shrinks the tape - where the temp that sets the brush on glue is far from shrinking or damaging the fabric. So I had some tape that I put down with 400* that i was sure was down - later lift with a finger nail.

So I end up going over a piece of tape at least twice with at least 2 different temps, because if you use the final temp to stick it down, you will ruin it- trust me.

Here are pics of the guns
I like the stienel ok but not worth that much more IMO.
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SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

I was inspecting tapes today that I put on yesterday with 420*

Most were good - but - there were spots on uneven surfaces (rivets) where the edge stretched between the top of rivet and the surface would lift with fingernail.

So I went over the entire edge with 430* and the edge seems to be down completely now.
- had to be careful and quick at this temp though, because anything that wasnt stuck down would start to curl in quickly at that temp.

Leason learned - round or clip corners on tapes because the sharp corners tend to curl and then wont stick down and must be trimed, or peel up when doing fingernail checks
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

The last comment I made about corners on tapes is the reason I would NOT buy pinked edge tapes in Oratex.
Just SAY NO.
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

How straight are your finish tapes?

I have really struggled with my tapes and keeping them straight while making sure they are stuck down well.
Its a good thing these Oratex tapes are nearly invisible.

Even If I get it all tacked down straight I can still shrink it too much by getting it too hot and make a very wavy edge.

The easiest way to keep this from happening is to use the iron at the right setting to do the final heat - but you still have to rub the tape into the fabric with the felt blade - I get impatient and think I can do it with the heat gun if I am careful enough - nope.

In the picture I have tacked the tape on one side of the leading edge at 370*
This light tack allows you to be able to lift and adjust without peeling glue off. Going around the leading edge required 4 passes with different heats to stick it down without wrinkles or distortion.

A foot or so in you can see where I stopped the second heat pass to roll the fabric over the edge without capturing air bubbles

So it seems like an easy decision - just use the iron for tapes - but you still have to use the gun to do the rivets.
Sooooooo... I did the whole thing with the heatgun - who needs straight lines anyway.
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SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

Back to the heat gun comparison:
They are nearly the same weight, but feel different in your hand. The Wagner seemed to leave me with less hand fatigue.
The Wagner gun is about 10* hotter - which is impossible to show with temp gun, but the way the tapes respond, i use less heat with that gun.
The Stienel gun has a better memory feature, every time you turn it on it goes to the temp you last used. The Wagner gun only remembers for that day.
But
I cannot trust the Stienel gun, several times I have inadvertently changed the temp somehow and it got so hot that I could smell it heating the metal nozzle. Only scorched one piece of tape, thankgoodness!!
After doing the tapes on one wing with the Stienel gun, I went back to the Wagner gun to finish up the other wing, I definitely like the Wagner gun better, but only a little, and the trust thing - because I am not careful enough.
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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Re: Oratex is like Yoga Pants

Post by Sierrakilo »

IMG_20181228_164611.jpg
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

SK
Tell us about the 600 weight material

Is it easy to stretch over the airframe?

How many wrinkles did you have to shrink out?

Was it easy to overheat and shrivel up at the edges?
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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Re: Oratex is like Yoga Pants

Post by Sierrakilo »

Bearing in mind I have exactly no experience with the heavier Oratex 6000....... Stretching the 600 over the frames was not too difficult using the heat gun and allowing enough waste material to properly grab....difficulty is not having enough hands to hold heat gun , pull fabric and apply pressure with felt pad all at the same time. Seems to be easy to mark the finish with edges of iron so plenty of care and use of silicon paper. I use a steniel gun set at 80-90 deg C for glueing and small hobby iron for the difficult to reach places.....Toko iron for initial shrink at 110 deg C and then second pass at 130- 140 deg C. Wrinkles do disappear so long as not too severe. Air bubbles in the glue and overworked glue can be a problem as shows through the fabric, got a couple of small areas of this, but hopefully not too noticeable with sides overlap and then tapes.
I thought that doing the wings would be more difficult getting the fabric stretched and glued around the tubular spar, but this proved easier than the fuselage so far........... not looking forward to doing the fin / top stringer area !!

TLAC Sherwood Scout is a modified Escapade . Beefed up fuselage and aerodynamic improvements ,extended elevators and rudder, metal tanks and metal header tank. Choice of TD or Nose gear and can have Rotax / UL260 / Jabiru or D Motor as powerplant. Highlander has not been approved over here in the UK as no previous builders and I didn't want to be first....However the SuperStol has been approved and several are in build and or flying here.
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BucF16
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Re: Oratex is like Yoga Pants

Post by BucF16 »

Happy New Year Shawn! Thank you for all of your posts!!!! Since in a month behind you in covering, they are immensely helpful. Just let me know if you stop........ and so will I. :D
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
Builder web site:
http://www.bruceshighlander.blogspot.com
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Re: Oratex is like Yoga Pants

Post by BDA »

Happy New Year Bruce! And everyone else !!
Im glad this thread is helpful!
It is really frustrating learning the hard way every time, hope I can help make it a little easier for the rest of you.

I am going to post more detail about the inspection rings, and then an overalll recap of my major mistakes, then I should be done. Everything is covered.

Unless I do the interior. Really wish I had done that first!!
SuperStol XL Alaskan With Titan 340
N331AK. Shawn Taplin
Wing extensions,Symetrical Airfoil tail ribs (NACA 21)
Mods in progress: Heavier struts, Double slotted flaps
Goal: 15mph no wind
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