Oratex is like Yoga Pants

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BlainS
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Re: Oratex is like Yoga Pants

Post by BlainS »

Shouldn’t there be 5 CM of glued lap? That is what I’ve been using as a minimum backing.
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CanadianSheepHunter
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Re: Oratex is like Yoga Pants

Post by CanadianSheepHunter »

BlainS wrote:Shouldn’t there be 5 CM of glued lap? That is what I’ve been using as a minimum backing.
My plan now is when i make the horizontal cut in fabric for the handle i will make that cut horizontally parallel to the bottom edge of handle or a bit lower as i have way more than enough backing plate below the handle. I will add a short vertical cut on the inside edges of the handle to make this work. I just really want the finished curve of fabric on top to be the same on each side for looks, and for clearance of the horizontal stabilizer bolts(which barely clear fabric) and to ensure same airflow on each side of vertical fin. There is places like the 1/2" stringer on top where there is minimal metal contact when the last piece is overlapped and apparently the strongest glue joints are where metal is below...the part that overlaps past that stringer on top where its only fabric on fabric is apparently no where near the strength of where the metal is below.
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CanadianSheepHunter
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Re: Oratex is like Yoga Pants

Post by CanadianSheepHunter »

BlainS wrote:By edge roller do you mean the flanging roller? I considered that too except that would leave the glue edge as the defining shape that shows through the fabric. I guess maybe mask it first. Might have to try a scrap to see what it will look like.

What if I put a layer of fabric between the “fingered” plate and covering?
Putting fabric on things will help hide imperfections, i used scrap Oratex to make my anti chafe tapes for my ribs and i could see how the extra layer helped hide imperfections but they still show through.
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

This all really good stuff that I wish I had done!!

Be careful not to ise too much Hysol, it ads weight, and a little works just as well.

Remember you have to put your data tag somewhere too - so that backing plate by the handle might be a good place to rivet to. I added a backing plate under the stabilizer, but should have put it by the handle I think.
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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CanadianSheepHunter
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Re: Oratex is like Yoga Pants

Post by CanadianSheepHunter »

BDA wrote:This all really good stuff that I wish I had done!!

Be careful not to ise too much Hysol, it ads weight, and a little works just as well.

Remember you have to put your data tag somewhere too - so that backing plate by the handle might be a good place to rivet to. I added a backing plate under the stabilizer, but should have put it by the handle I think.
Thanks...now i know where my data plate is going! Yes i used too much Hysol...my thinking was I've had the hysol pop off when manipulating pieces so i put extra to help when i bent the top half...i hate adding weight for sure...Im that guy that will use too much glue or too much goo lol
Clark in AZ
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Re: Oratex is like Yoga Pants

Post by Clark in AZ »

Hey Kenny,

If your having Hysol pop off stuff, I think you need to be more aggressive prepping your parts? I was told at the factory to use 60 grit sand paper and get after it with a really good scuff. Then a good cleaning with lacquer thinner or acetone. Doing this, I've never had any pop off.

Looks good, thanks for posting the pics...

Clark
Building SuperSTOL Kit 512
Cave Creek, AZ
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CanadianSheepHunter
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Re: Oratex is like Yoga Pants

Post by CanadianSheepHunter »

Clark in AZ wrote:Hey Kenny,

If your having Hysol pop off stuff, I think you need to be more aggressive prepping your parts? I was told at the factory to use 60 grit sand paper and get after it with a really good scuff. Then a good cleaning with lacquer thinner or acetone. Doing this, I've never had any pop off.

Looks good, thanks for posting the pics...

Clark
Good reminder the 60 grit. I cleaned/prepped aluminum with Bonderite and then alodined...which calls for purple scuff pads. Then Epoxy Primed but I only scuffed the epoxy primer with the purple scuff pads(should have used 60 like you say) Where I had it pop was lower wing attach point and next day I decided to tweak the aluminum lots on the one side...I pulled hard and because it popped off in one spot actually helped me get the alignment wanted to match fabric flow on that one. I put more hysol behind it to get it where it needed to be. At least once the fabric is all on these fabric backing plates will be way more solid. But good point should have used 60 grit below hysol.
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BDA
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Re: Oratex is like Yoga Pants

Post by BDA »

I think on important parts I would alodine AFTER scuff w 60grit
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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BlainS
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Re: Oratex is like Yoga Pants

Post by BlainS »

Decided to keep moving. Sometimes you lose sight of what your building. It’s not a Swiss watch. Up to 65 backing plates so far.
Using the PTI chromium primer. It survived the pull test but I’m not impressed so far. You can see areas that I wiped excess Hysol off with lacquer thinner. I’ll touch those up before glue time.
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CanadianSheepHunter
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Re: Oratex is like Yoga Pants

Post by CanadianSheepHunter »

BlainS wrote:Decided to keep moving. Sometimes you lose sight of what your building. It’s not a Swiss watch. Up to 65 backing plates so far.
Using the PTI chromium primer. It survived the pull test but I’m not impressed so far. You can see areas that I wiped excess Hysol off with lacquer thinner. I’ll touch those up before glue time.
Is 65 backing plates a typo...if not can’t think where else they are needed other than Rudder horns, and cable attach points on stabilizer.
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BlainS
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Re: Oratex is like Yoga Pants

Post by BlainS »

Not a typo. However some penetrations required 2 halves. I covered the baggage and the area next to the seats. Each floor mounting tab got backing. Tie downs, fair leads, etc. Not going to let the Oratex get away.

Actually I forgot to add the gear mounts. That’s 3 more.
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CanadianSheepHunter
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Re: Oratex is like Yoga Pants

Post by CanadianSheepHunter »

BlainS wrote:Not a typo. However some penetrations required 2 halves. I covered the baggage and the area next to the seats. Each floor mounting tab got backing. Tie downs, fair leads, etc. Not going to let the Oratex get away.

Actually I forgot to add the gear mounts. That’s 3 more.
When you say each floor tab got backing i dont see the need for that, and are you using Oratex for baggage floor?
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BlainS
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Re: Oratex is like Yoga Pants

Post by BlainS »

Negative. Only the side panels in baggage area and back panel.So when you wrap around the lower longeron the fabric gets cut for tab protrusion. That leaves the Oratex without support the width of the tab. Might be overkill but no way the fabric will relax over those tabs and cause a wrinkle.
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BlainS
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Re: Oratex is like Yoga Pants

Post by BlainS »

I mentioned in an earlier post that I’m not impressed with the PTI chromate primer. Well here is what it did to me:
CF7988B2-A085-4D15-A91E-2CCA85CAB2B1.jpeg
3E30876B-59C4-45E9-8482-582C0AE77023.jpeg
Roughed up with 80 grit. Wiped clean with lacquer thinner, 1 tack coat, 1 semi wet coat on 80 degree day. I see no adhesion of this material. This backing plate was glued with Hysol. Since it it a self etching primer I expected it to adhere better. Going back to 2k primer.

For everyone who used this primer under Oratex expect it to fall off any day. Just kidding, of coarse.

On the same subject neither do I care for Hysol. Too easy to peal off of prepped aluminum. If I do another Just ship I will probably use ProSeal.

Shawn- not hyjacking- seems relative to the thread.
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Clark in AZ
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Re: Oratex is like Yoga Pants

Post by Clark in AZ »

I had similar results with rattle can Rustoleum self etching primer. I went back to 2 part epoxy primer.

Clark
Building SuperSTOL Kit 512
Cave Creek, AZ
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