Question about ordering Kitfox Series 7 STi Firewall Back Kit. Planing to Use Oratex

[Markhoran@hotmail.com]

Hi

I am ready to put my order in for the Kitfox Series 7 STi Firewall Back Kit. Planing to Use Oratex. Do I exclude the "Covering Kit" but still order the "Lacing Kit?" Is there an order form for sub kits? Just seeing the one order form.

Thanks,

Mark Horan

[DesertFox4]

What a great first post! Let me be the first to say- Congrats Mark!
Give Kitfox Aircraft a call.
208-337-5111 will get you to someone to help you with the order process.
Best wishes and keep us posted.

[Geek]

The good news - you're ordering!! I can tell you from experience that is an exciting time. The bad news - waiting really bites!!! But when the kit comes - it is quite the event.

I am also building the STi and using Oratex. I excluded the Covering Kit and the Lacing Kit. The lacing kit uses a wax impregnated string that Oratex glue does not like and they say not to use it. The lacing that Oratex recommends is round rather than flat like 'normal' lacing so it sticks up a bit more on the wing which some don't like the looks of. I have read where some don't lace the Oratex at all and some get the normal lacing and treat it to remove the wax before lacing. I would exclude the lacing from the order and then (cause you have some time between now and when you need it) do some research and figure out which way you want to go. Lacing is cheap.

Congrats on that first step to the adventure!!

Gary

[Denalifox]

The good news - you're ordering!! I can tell you from experience that is an exciting time. The bad news - waiting really bites!!! But when the kit comes - it is quite the event.

I am also building the STi and using Oratex. I excluded the Covering Kit and the Lacing Kit. The lacing kit uses a wax impregnated string that Oratex glue does not like and they say not to use it. The lacing that Oratex recommends is round rather than flat like 'normal' lacing so it sticks up a bit more on the wing which some don't like the looks of. I have read where some don't lace the Oratex at all and some get the normal lacing and treat it to remove the wax before lacing. I would exclude the lacing from the order and then (cause you have some time between now and when you need it) do some research and figure out which way you want to go. Lacing is cheap.

Congrats on that first step to the adventure!!

Gary

I used wax lacing on mine. Trick is to strip the wax prior and then when encapsulate the stitches in the glue. Zero issues so far. Non waxed lacing becomes troublesome to slip the knot under the fabric so keep that in mind. I HIGHLY recommend rib lacing with Oratex. Reason being is if you dont you are now relying on the Rib cap hysol bond. They were not designed for that. The Oratex glue may hold just fine and dandy, whos to say the thin bonded cap strip wont let go. Airplanes do funny things when Cold/hot.

[efwd]

Get the Wax thread and strip it. I used the round thread from Better Aircraft Fabric. These two were the only options and back then Lars really discouraged the use of waxed thread. Whish I had stripped the wax and used the flat thread. The flat threads are going to look so much better than mine IMO. If you use flat thread you will not be concerning yourself with the voids that remain on either side of the round thread. I had to drop glue over the top of every stitch so that the tapes had something like a ramp on either side of the stitch. I don't recall how most people are cleaning the wax off, acetone or hot iron? Cetainly somebody will advise here.

[Denalifox]

Get the Wax thread and strip it. I used the round thread from Better Aircraft Fabric. These two were the only options and back then Lars really discouraged the use of waxed thread. Whish I had stripped the wax and used the flat thread. The flat threads are going to look so much better than mine IMO. If you use flat thread you will not be concerning yourself with the voids that remain on either side of the round thread. I had to drop glue over the top of every stitch so that the tapes had something like a ramp on either side of the stitch. I don't recall how most people are cleaning the wax off, acetone or hot iron? Cetainly somebody will advise here.

I just used a razor blade. I would pinch the lacing between the table and the blade and pull it through. Worked like a charm. Then Clean with denatured alcohol. Just enough wax to slip the Staggerwing knot under without binding but not to cause issues when applying tapes.

[Shadowrider]

Or...save your money and time. Rib lacing not required with Oratex and 1” cap strips.

[Cherrybark]

Used flat, waxed thread. Measured a length of thread to knot one rib. Used a thumbnail to scrape both sides of the thread then wiped with alcohol. A razor blade sounds like a great approach. Not perfectly clean thread but the little bits of remaining wax were not a problem. The flat thread lays neatly against the fabric and you won't have to deal with the little glue-less "pup tents" along every rib stitch. Rib stitching may or may not be necessary with modern glues but it's a satisfyingly last step in covering a fabric wing. Another vote for the Staggerwing knot. You'll be recreating a bit of airplane history as you work.

The flat waxed thread is also perfect to use to secure wiring throughout the project. Plastic zip-ties are quick but scratching your hand or arm against those sharp cut-off tails can get old. https://www.kitplanes.com/wire-bundle-lacing/

[Denalifox]

one thing to note about Oratex. I know quite a few builders/pilots that have an Oratex covered aircraft. All of them to include me have had issues with Tapes and corners lifting. In fact I had I trailing edge tape lift and come off last week. Plane started pulling, I looked over and was trailing about 10' of 2" tape that was wrapped around my Flapperon bracket. It was just a vanity tape but still scared the crap out of me. I have see Black Oratex after sitting in the sun shrink so tight it buckled ribs and then completely release (not in flight thankfully). That being said, My plane lives outside and currently its been 20 degrees overnight. Other than that tape lifting I have had no big issues. It will slack in the cold so retightening will be needed at some point. Its a very finicky system that requires ALOT of thoroughness when applying. Don't let that scare you.

Sidenote: Two days ago I was tightening some looser spots and my Oratex Toko T14 supplied Iron grossly overheated and I burned a hole in the bottom of my wing. Everything was going great and all of a sudden I heard a rip. Lifted the iron and there was a hole. Luckily it was a pretty simple fix (due to the nature of the system).

[Cherrybark]

Curious about the glue you used when repairing the hole. The factory insists on pre-mixing their glue and shelf life is a concern. Would be nice to hear Lars was stocking small bottles for repairs.