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yocum137
07-23-2020, 02:34 PM
Well, the journey began today. I purchased the deposit that a builder posted on Barnstormers and my kit's production date is April 2021. I'm live in the shadow of Lucky Peak on the SE side of Boise, hence the name - One Lucky Fox.

Plans always change, but I can say for certain that I have settled on the STI version. I'm about 90% sure I'll go with the 915is engine to compensate for the higher elevations in Idaho. We moved here from the Midwest where I had a Pietenpol Air Camper (N8031) which was decent plane for flying at low altitudes over a huge runway (i.e., corn and bean fields). But, flying in/near/around mountains is definitely going to be different so extra power is warranted, I think.

Can I Go Fly Today Peter Rabbit?

DesertFox4
07-23-2020, 03:01 PM
Congratulations Dan. The Kitfox STi and a 915 is an Idaho backcountry pilot’s dream.👍 Very best of luck.

yocum137
07-23-2020, 04:53 PM
Thank you!

efwd
07-23-2020, 08:48 PM
Congrats Dan! Sounds like your going to have quite a ride.

yocum137
07-24-2020, 10:42 AM
Congrats Dan! Sounds like your going to have quite a ride.

Thanks, Eddie! I'm looking forward to it - kinda bored just doing the same thing every day in quarantine: sleep, walk, eat, work, repeat. In the meantime I've been slowly building a Piet (I sold N8031 in '12). Ribs are almost done. I'm ordering spar material from AC Spruce, this weekend. I figure I can get the wings done by the time Debra calls me to pick up the kit. In the meantime, I just keep watching my own old videos: https://youtu.be/ddUgZzWq0js

;)

bbs428
07-24-2020, 03:26 PM
Welcome and congratz! :D

All the best

yocum137
10-15-2020, 11:51 AM
Wow! Heather at Kitfox just sent me an email and someone needs to delay their shipment due to coronavirus uncertainties, and since I'm local in Boise, we swapped production slots! My kit will arrive in early December! All of a sudden I'm nervous and excited.

If you're the person who swapped with me, thank you very much!

Now I need to find a place to put away all the Pietenpol pieces I've been making in the meantime. ;)

yocum137
12-23-2020, 09:06 AM
Santa showed up on Monday morning with some airplane parts. (Thank you Brandon and Heather!)

https://photos.app.goo.gl/jpfbwPkAVz9jvPzG6

DesertFox4
12-23-2020, 09:20 AM
Airplane parts make the season brighter. Congrats.! 👍

Frontier Fox
12-23-2020, 08:39 PM
Did Brandon and Heather have their elf costumes on?

yocum137
12-24-2020, 11:44 AM
They were and they let me peek at the Naughty List, too, but I was sworn to secrecy! 😉

yocum137
01-17-2021, 11:16 AM
Metal movement has commenced.

The inventory took a few days over Christmas break. It was very satisfying, almost zen-like. Start with Box 1, lay out the bags, find the PN in the inventory sheet and mark it off. I was only stumped by 3 items - the fuel placard sheets are in the big white, sealed envelope. Open it to find the PNs. The STi wing kit box is listed on the sheets as a separate item. If you get to the end and that’s the only item not checked, you already inventoried the box (it’s in box 8, fwiw). Lastly, the hinged turtle deck instructions were missing. Heather emailed me a copy and that was it.

Here’s my 2c on reaming.

tl;dr: file down the round end of the reamer to fit into a nut socket; takes 10 minutes. Then use a screw-driver with flex extension, 7/16” nut fitting, attached to the reamer. Use painters tape to affix popsicle sticks to the horizon stab to prevent scratching.

Dad was a sucker for cheap tools and barn sales. 30+ years ago he bought me a screwdriver with a flex extension. I hated that thing, but I couldn’t bring myself to throw it away. Well, today it earned its keep.

https://photos.app.goo.gl/9gPSCn37y7L8GA6U7

yocum137
03-13-2021, 01:07 PM
Work has been ongoing. Slower than I want, of course, but it’s been steady. So far the best purchase I’ve made is the table drill press. I’ve used it for a bunch of stuff including sanding the horizontal stab ribs to size. Take a round pencil, wrap masking tape around it until just under size of the LE tube, then wrap some 100 grit sand paper and tape it on. 600 RPM and sand away.

https://photos.app.goo.gl/1Sh5LSBxaa3ZrqCA6

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yocum137
03-13-2021, 01:21 PM
Sizing the bearings with sandpaper was taking too long, so I mounted them on the drill press and used a single cut file for the rough sizing. 600 rpm, 10 passes at medium pressure takes off 1mil of size. About 40 passes takes enough metal off for the bearings to fit in the bushings.

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yocum137
03-13-2021, 01:27 PM
To press the bushings into the horizontal and elevator fittings, use a long course thread bolt with extra nuts and tighten. Slow and steady and no need to use Locktite.

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yocum137
03-13-2021, 01:40 PM
I glued up the rib stiffeners before installing on the plane. Laid flat, no need to use flox in the epoxy. Also, I used sandwich baggies with an itty-bitty hole cut in the corner (1/16”) to apply it like cake frosting. You can mix up about 2/3 oz. at a time before the epoxy sets up too thick to squeeze.

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yocum137
03-13-2021, 01:46 PM
My first screw up. The ribs closest to the fuse NEED to be pressed up against the metal on the horiz stab to allow for the vertical stab sheet metal installation. I used a medium course wood rasp (double-cut file) to carefully file away the epoxy. When the ribs were off, I used a Dremel tool with course sandpaper barrel to sand off the epoxy to remove the rib stiffener. Live and learn (and read the fine print!). This is the WRONG way to install the ribs:

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yocum137
03-13-2021, 01:53 PM
One of the other builder (apologies, I haven’t memorized names, yet) discovered that the foam used for the stab and elevator tips melts when covering with Oratex, so I ordered some balsa blocks and used that instead. They turned out pretty good, I think.
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yocum137
03-13-2021, 01:57 PM
Installing the horizontal poly blocks. Have I mentioned that I really like the drill press I bought?

Note: the builders kit doesn’t include a #34 bit to drill these holes. Booo!

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Kitfox Pilot
03-14-2021, 05:52 PM
Your build is coming along very nice.

yocum137
03-14-2021, 06:30 PM
Your build is coming along very nice.

Thank you, sir! I’m curious, did you take the horizontal stab off to cover? I haven’t tightened any nuts more than finger tight and I’m curious if I should.

Thanks!
Dan

Kitfox Pilot
03-14-2021, 07:36 PM
Yes it will have to come off to cover and other reasons. I know how you feel, it would be nice to leave on. I'm hoping mine is going back on for good in a few days!

Mark123
03-14-2021, 08:38 PM
It’s looking good. I’d recommend picking up a #12 reamer (.1890), as many of the bolts will not slide in after reaming at .1875. Harlan gave me that tip. I’m about 10 weeks into my build, and having a blast so far.

yocum137
04-24-2021, 01:57 PM
It’s looking good. I’d recommend picking up a #12 reamer (.1890), as many of the bolts will not slide in after reaming at .1875. Harlan gave me that tip. I’m about 10 weeks into my build, and having a blast so far.

Huh. So far I haven't had to ream any larger than 0.1875, but I suspect you're farther along than I am. *shrug*

yocum137
04-24-2021, 02:12 PM
Control sticks are assembled and I just installed them, but dang! the control in pitch is really tight after I torqued to the recommended 20-25 in-lbs (2 ft-lbs). Is it ok to back this off to get free movement?

The block deformed so much it was pinching the column. I backed off 4 turns before it freed up enough that I was satisfied, and I've still got 1 thread showing past the nut so it meets the minimum, so sayeth AC 43.13 Chapter 7, page 11, section 7.63(f) (After the nut has been tightened, makesure the bolt or stud has at least one threadshowing past the nut.) but is this good enough?

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airlina
04-24-2021, 03:20 PM
I had to sand material off the bearing block for a proper fit. This would be preferable to loosening the AN bolt/nut torque. There should be no pinching whatsoever of the torque tube when torqued to the recommended torque. A bit at a time off the block (then test) so you don't overdue it . Bruce N199CL

yocum137
04-28-2021, 09:19 PM
Had a pretty good day. Elevator is hooked up (nuts aren't tightened, of course):


https://photos.app.goo.gl/KXArXUM5bfs1xJT59

And a few notes:

Pro tip #1: for reaming and cleaning out the various threaded holes that get gummed up with powder coat, use cutting fluid. Totally worth it. Cuts like butter.
Pro tip #2: you will bung up the roll pin for the flap handle. It's a soft metal, not hardened, and pressing/tapping it in will deform it. 1/16" x 3/16" hardened roll pins can be had on Amazon, 500 for $18 or 30 for $10 (in 2021).
Pro tip #3: a round 8" by 5/16" b astard file is your best friend when fitting the wood tail ribs and floor boards around the welds.

yocum137
04-29-2021, 08:09 AM
Pro tip #2: you will bung up the roll pin for the flap handle. It's a soft metal, not hardened, and pressing/tapping it in will deform it. 1/16" x 3/16" hardened roll pins can be had on Amazon, 500 for $18 or 30 for $10 (in 2021).


* 1/16"x3/8"

jrevens
04-29-2021, 09:46 AM
Hmm... The roll pin I received was a “standard” roll pin (or “spring pin”)... nothing soft about it.

jiott
04-29-2021, 10:04 AM
Same with mine.

yocum137
04-29-2021, 11:11 AM
Huh. Mine was silver colored and with the first tap on the tool it started to deform/spread the end. I ended up drilling it out and replacing it with one of these, which went right in:

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yocum137
05-01-2021, 09:36 PM
I got the adjustable pedal kit and these are the 1/16" roll (aka tension) pins that came with it. In the picture I included, and used, the anodize black pins I bought from Amazon:

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yocum137
05-01-2021, 09:43 PM
Another pretty good day. Working on installing the center console.

Pro tip: An 8" benchtop drill press is an excellent investment. ~$80 from a big box home goods store. So far I've used mine for drilling, filing bearings, and sanding. Today I used it to countersink. I set the depth gauge, used a #1 bit, and it'll countersink the 1/8x1/4 flush pop rivet holes all day long:

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yocum137
05-09-2021, 01:29 PM
Ah, the dreaded rudder pedal binding/freeness issue everyone has had. Read these threads:

https://teamkitfox.com/Forums/threads/8120-Rudder-Pedal-question
https://teamkitfox.com/Forums/threads/6165-rudder-pedal-freeness

The brake pedals are free (after sanding on the drill press), the center T's are free. The outer T's that rotate on the black bearings... not so much. I'm taking the black bearings out, pulling them on the drill press and sanding them down a few mil.

yocum137
08-02-2021, 04:07 PM
Control sticks are assembled and I just installed them, but dang! the control in pitch is really tight after I torqued to the recommended 20-25 in-lbs (2 ft-lbs). Is it ok to back this off to get free movement?

The block deformed so much it was pinching the column. I backed off 4 turns before it freed up enough that I was satisfied, and I've still got 1 thread showing past the nut so it meets the minimum, so sayeth AC 43.13 Chapter 7, page 11, section 7.63(f) (After the nut has been tightened, makesure the bolt or stud has at least one threadshowing past the nut.) but is this good enough?



I stopped by Homedale the Friday before everyone headed to Oshkosh and told Brandon and Heather about my control stick torque block solution - sleeve the AN3 bolt in a 4130 round 0.065" thick tube. Brandon's eyes went glassy and said, "Ooooooh, I like that!"

Here's the tubing I bought: https://www.mcmaster.com/89955K539/

Below is what it looks like. The proper torque is easy to achieve and the nylon block doesn't deform and pinch, i.e., no sanding nylon! Super easy solution!

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alexM
08-02-2021, 05:14 PM
Brilliant. Great idea.

yocum137
08-16-2021, 11:00 AM
Well, all the mechanicals are done on the fuselage so I hung it from the ceiling joists and started reading up on the STi wing installation. Guess I need to pull the fuse back down sooner rather than later. Ah well.

In other news, I'm an idiot. I laid one of the tanks in the wing hole last week just to see what's what. Today, not thinking, I turned the rotisserie and BANG! the tank fell out. So, so stupid. I'm using engine stands and it landed right on one of the metal supports, dinged the fiberglass. I'm open to suggestions on how to fix this:

- Proseal from ACS?
- Someone used this stuff: https://www.hirschauto.com/ALCOHOL-RESISTANT-GAS-TANK-SEALER/productinfo/GTS/ ?
- Lay up another layer or 2 of fiberglass over the ding?


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Thanks,
Dan

rv9ralph
08-16-2021, 11:15 AM
I would contact Brandon at the KF factory to find out what resin he uses to ensure compatibility and resistance to alcohol in fuel. Then, sand a shallow scarf around the damage and start a build up of several layers starting with small size patch and enlarging the sizes of the patches by a half inch beyond the previous patch.

Ralph

yocum137
08-16-2021, 11:33 AM
I would contact Brandon at the KF factory to find out what resin he uses to ensure compatibility and resistance to alcohol in fuel. Then, sand a shallow scarf around the damage and start a build up of several layers starting with small size patch and enlarging the sizes of the patches by a half inch beyond the previous patch.

Ralph

Thanks Ralph - Yeah, I sent Brandon an email already.

The Proseal isn't recommended on fiberglass, afaict. I'm looking at these 2 epoxies while I wait for Brandon's reply:

- EZpoxy at ACS: https://www.aircraftspruce.com/catalog/cmpages/ezpoxy.php?clickkey=8187194
- MAX GRE: https://theepoxyexperts.com/shop/adhesives/chemical-and-water-resistant/max-gre/max-gre-48oz-epoxy-resin-gasoline-resistant-4-coating-glue-fiberglassing-carbon-fiber/

Dan

yocum137
08-21-2021, 12:53 PM
I'm inspecting rib squareness on ribs #1, 3, 5, 7, and 9 - these are the ribs that the flaperon hinges attach to - and they're not quite square. Just under 1/32", but still. What'd y'all do? Place a shim under one side of the hinges to get them square to the flaperon?

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efwd
08-22-2021, 07:56 AM
When I was building my RV-4 back in 2000 I was on the phone with MR Vansgruven who stated "your not building a space shuttle". What you have there is not a problem whatsoever. Just wait until you go to hook up the first hinge to the flapperon control horn. It will likely be so out of alignment that you may need to bend the bracket into a slight S shape for the bolt holes to line up. It all works fine in the end.

Delta Whisky
08-22-2021, 09:02 AM
What Eddie said is good, general guidance. You'll get a chance to help with some of the alignment issue you have detected but in so doing you might run into a short edge distance issue with the aluminum reinforcements that go on the trailing end of the ribs. Then, you will try to eliminate some of the SED issues by placing the flapperon horn on either the outside or inside of the bracket vs. sandwiching the horn(s). One or two horns might have to be spaced with a washer from the bracket to make sure the horn does not rub on the skin of the flaperon. You might have to make one or two passes thru these steps so don't drill all of the bracket holes until you feel comfortable with the alignments. And, as Eddie said, some of the issues will be eliminated with a little scientifically applied force de jure. It might be challenging but fun and rewarding when complete. A bunch of tolerances are stacking up and the end steps have to tolerate that fact.

yocum137
08-24-2021, 11:16 AM
Thanks guys for the sage advice and resetting my expectations correctly. It certainly ain't a space shuttle, that's for sure. :D

yocum137
09-25-2021, 03:49 PM
The bends of the flaperon brackets are mere suggestions. 😂

You need to bend them properly so the bends are square and the right and left bracket pieces are square to each other.

before:

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after:
28832

the batch:
28833

yocum137
10-02-2021, 06:33 PM
Stopped by the factory in Homedale a few months ago and a gent was passing through after fabricating carbon fiber flaperon ends which I thought were pretty neat so I made my own.

I also discovered the #1 best way to dull a flat file. Use it on carbon fiber! 🤣😖

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yocum137
12-17-2021, 10:55 PM
I have a small workshop - too small to put the wings on and take them off repeatedly - so I bought the pre-rigged wing option from Kitfox.

The pre-rig option sets 4 things:

* dihedral
* washout twist
* wing sweep
* distance between rear and front spar attach points

The construction guide instructs the builder to attach the wings to the fuse prior to installing the root rib, rib #1, and the tanks.

As I said, I have a small shop, so after some thinking I figured out how to install the root rib and tank without installing the wings in the fuse. The solution is simple: a steel jig that sets the distance and hole angle the same as the fuse mount points.

First clamp a length of angle iron on the lower side of the fuse mounts and drill through the points with a size N drill bit and ream with 0.1325” reamer:
29500


Next, place the angle on top of the fuse mount points, insert the AN 5-31 long bolt through the rear hole, clamp tightly and drill up through the the front mounting hole into the angle iron and ream:
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Et Voil*. The properly angled holes mounted to the wing. This provides the proper spacing to size the root ribs properly:

29502To maintain the washout twist when gluing in the tanks, with the wing set on 2 saw horses, place a 1/2” block under the rear spar at the 159” point, close to rib #9.

yocum137
12-17-2021, 11:04 PM
Here are some pictures of how I installed landing light brackets in the STi wing tips. I did not cut out the entire internal 'glass tubing, just enough enough for the AeroLED lights to fit into the space:

29503

The fiberglass is too thin to hold a screw, so I bought some 1/8" aluminum and bent it to match the airfoil on the backside of the light brackets and hysol'd them into place. I'll drill through this and tap the holes for #6 stainless flat head screws.
29504

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Nice flush fit. The plexi lens fights exactly even with the airfoil.
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yocum137
04-15-2022, 05:44 PM
In section D, Flight Control Rigging, page 33, it says to use a 2 13/16 block placed against the bottom of the front spar. I'm sure this is for the normal airfoil, not the STi wing. What size should that block be for the STi?

Kitfox Pilot
04-15-2022, 07:06 PM
I will have to check but I'm pretty sure I used a 2 13/16 block on mine.

yocum137
04-16-2022, 11:38 AM
Hm. Thanks Harlan. My *minor* concern is that in cruise flight, no flaps, the flaperon will have a slight *negative* AoI due to the additional 1/4” or so of thickness on the LE of the STi airfoil at the front spar location. High performance gliders use negative flaps at high speeds, but this ain’t no laminar flow airfoil. 😉

I’ll ask John and Brandon on Monday, too.

yocum137
04-23-2022, 02:49 PM
I've moved on from the flaperon Angle of Incidence - I'll come back to it.

Next question: flap push-pull tube adjustment. No matter how hard I try, I can not get the angle between the flap tube control horn and the bottom of the plane to 11.5 degrees - there just aren't enough threads on the push-pull tube screws. Best I can do is 13.5 degrees (see picture 1 and 2, below). But, even if I could, I'd never be able to get the flap handle into the #3, full flap detent. The mixer tube hits the bottom of the cargo area (see picture 3 and 4).

What am I doing wrong?

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30282

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rv9ralph
04-23-2022, 04:27 PM
Look at figure D-2 on page 35 of the Final Assembly section of the Build Manual. The reference for the "Flap Bellcrank" to measure the 11.5 degrees shows that as the part of the assembly that connects the "flap" portion to the "aileron" portion.

Your picture shows you measuring the portion of the mixer that attaches to the flap handle pushrod.

I hope I both assessed your pictures correctly and explained my interpretation correctly.

Ralph

yocum137
04-24-2022, 06:22 PM
Thanks Ralph. I’m a knucklehead some days. Everything else measures perpendicular from the bottom of the floor tubes, and I completely missed that part of the diagram.

In case anyone wants to use the mixer bell crank, instead of the a flaperon bell crank, the angle is 27.1º from vertical, 117.1º from the bottom of the floor tubes. See photos:

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rv9ralph
04-24-2022, 09:14 PM
No problem, glad I could help.

You are making good progress.

Jez
07-04-2022, 04:01 PM
I stopped by Homedale the Friday before everyone headed to Oshkosh and told Brandon and Heather about my control stick torque block solution - sleeve the AN3 bolt in a 4130 round 0.065" thick tube. Brandon's eyes went glassy and said, "Ooooooh, I like that!"

Here's the tubing I bought: https://www.mcmaster.com/89955K539/

Below is what it looks like. The proper torque is easy to achieve and the nylon block doesn't deform and pinch, i.e., no sanding nylon! Super easy solution!

28512
This is great, but over in the UK I could not find any steel tubing to that size. So had a little think and thought what about carbon fibre! so I found a 400mm length to the correct o/d and I/d for £ 10. Very happy thanks

yocum137
07-05-2022, 12:32 AM
This is great, but over in the UK I could not find any steel tubing to that size. So had a little think and thought what about carbon fibre! so I found a 400mm length to the correct o/d and I/d for £ 10. Very happy thanks

👍🏻👍🏻

Make sure add your source to your log so the next UK builder can find it easily. 😉

yocum137
09-13-2022, 06:04 PM
Progress has been slow but steady. Just about everything is in the fuse and I'm finally about to start covering with Oratex.

Overzealous and over estimating how close I was to being done, I bought my Oratex last year right before Oshkosh. As some of you know, Oratex claims their adhesive has a strict shelf life of 90 days from manufacture. Well, it's been 14 months with the adhesive on the shelf and I decided to do a little experiment to see how "strict" their recommendation is. The executive summary is that if it's stored at 72F in a pitch black room it's still effective after all this time. I'm going to reach out to Better Aircraft Fabric to verify my findings.

Their test procedure is straight forward and described in the manual. 15x2.5cm strip attached to a representative sample of material (capstrip) pulled straight off at 90 degrees with a static force of no less than 3.9 lbs (3lbs 14.4oz), apply more force until it starts to separate, ease back off to 3.9lbs and it must hold. I nearly tripled the static force - 12lbs 6oz - and it held.

Here's the photo evidence:

https://photos.app.goo.gl/KAUCZQtaxseNhQcG7

yocum137
12-16-2022, 01:22 PM
Well, first wing is covered with Oratex. "Mistakes were made" but just cosmetics - nothing structural. I don't have any experience with Polyfiber, but I do like the fact that once Oratex is on, it's done.

https://photos.app.goo.gl/SDhpqy8sSFG9zc6e8

yocum137
12-16-2022, 01:25 PM
Oh, another thing... if anyone has a Rotax 915is they'd like to sell me, let me know! Debra at Kitfox says Rotax isn't accepting orders for the 915 until mid-Feb 2023. No word on what's causing the issue, but it is making me consider the EDGE Performance option...

Kitfox Pilot
12-16-2022, 05:34 PM
It is looking good! That's a nice bright color.

yocum137
12-16-2022, 07:36 PM
See and be seen! 😂

Besides, planes fly better when they’re Cub Yellow!

rv9ralph
12-16-2022, 07:57 PM
Wow... Oratex comes in colors other than silver and cream?

bbs428
12-17-2022, 10:32 PM
Well, first wing is covered with Oratex. "Mistakes were made" but just cosmetics - nothing structural. I don't have any experience with Polyfiber, but I do like the fact that once Oratex is on, it's done.

https://photos.app.goo.gl/SDhpqy8sSFG9zc6e8


That looks great and just like that you're done! I am envious!
You'll get better as you go. Don't be afraid to recover as it's only $$ and you will have to live with any mistakes for a long time! Easy for me to say...Lol!
Hopefully, if there are any recovers, will be on a small surface! All the best!

yocum137
01-27-2023, 11:35 AM
Nobody tells you about the process to put on Oratex reinforcing tapes. Lots of masking tape to get the glue in the right places. Area to be glued should be 1mm smaller than the size of the tapes on each edge.

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Geek
01-28-2023, 07:22 AM
Wow - that tape job is attention to detail!! Couple questions. Are you going to do the rib lacing or going without? (I am still on the fence for this. Some do - some don't) I was under the impression that reinforcing tape and finishing tape were the same and the finishing tape came with glue on it. Are you cutting your own tapes?

Again - really nice work!!!

Gary

yocum137
01-28-2023, 11:49 AM
Hi Gary,

I’m not going to do rib lacing. The adhesive is OMG strong. Once it’s on, it does not come off without the application of extreme heat - 200C. It’s not like Polytack which, apparently, pulls off really easily.

Reinforcing and finishing tapes are the same thing and yes, they’ve got an adhesive pre-applied. It’s not the same adhesive as the stuff you get in the bottles from Oratex, however. It’s designed to be heat released for ease of placement - or so the application manual says. The liquid stuff is not: once it’s on, it’s on.

So for reinforcement on sharp edges (per AC43.13 2-13c) you apply the liquid stuff and lay the adhesive backed tape into it and heat it to stick it down. One note - I said 1mm between adhesive and edge. Now that I’ve done a few, I wish I had made it 2.5mm. The 600 finish tapes shrink up a lot more than the 6000 fabric. Live and learn. At least acetone takes the adhesive off without stripping the latex paint from the skin.

Speaking of the Oratex manual… it’s a hard read. Stuff is willy-nilly, everywhere, so I made up a summary of the temps, times, underlying surfaces and materials. I’ll send that in another post.

Dan

alexM
01-28-2023, 02:01 PM
Are you talking about the factory manual being a bit scattered or the Tips and Tricks manual that Lars created? He has nothing nice to say about the factory manual and I tend to agree. His is much better.

yocum137
01-28-2023, 03:08 PM
Factory manual.

Lars wrote a hints and tips manual?? Where’s that?

yocum137
01-28-2023, 03:19 PM
Alex,

Are you talking about this?

https://betteraircraftfabric.com/instructions.html

Dan

Kitfox Pilot
01-28-2023, 04:35 PM
This one, BAF Oratex Tips & Tricks Reference Guide July 2020.pdf (file:///C:/Users/3/Downloads/BAF%20Oratex%20Tips%20&%20Tricks%20Reference%20Guide%20July%202020.pdf)
file:///C:/Users/3/Downloads/BAF%20Oratex%20Tips%20&%20Tricks%20Reference%20Guide%20July%202020.pdf
I got mine after I was almost done covering. They are not real good sending manuals.
Sorry I can't get it to load on here or open. Hopefully someone else can.

alexM
01-28-2023, 07:15 PM
^Thanks Harlan, that's the one.

yocum137
01-28-2023, 08:56 PM
Harlan emailed me a copy so I put it in my Google Drive in case anyone else wants it:

https://drive.google.com/file/d/1Rtz238d_bLESh1_wECWfm2rxSO2sn7Y2/view?usp=drivesdk

Thanks, Harlan!

Dan

yocum137
01-29-2023, 09:47 AM
Gary,

I was wrong! Reinforcing tapes and finishing tapes are different!

Since I’m not stitching I know nothing about reinforcing tapes - these are the tapes that go between the rib stitching and the fabric.

I *am* applying “finishing” tapes to any sharp edge - the ribs and false ribs - per the AC43.13 2-13c I mentioned before. That “reinforces” the fabric and will add extra strength to it.

I really wish I had got a copy of Lar’s tips and Tricks manual from the get go. Ugh.

Dan

Geek
01-29-2023, 10:30 AM
Got it Dan and thanks for the follow up. You hit the genesis of my original question about the two because you laid it out so well but the false ribs don't get stitched. Was afraid I had missed something along my way. Couldn't agree more with all the comments on the manuals versus Lar's instructions and such. Lot of chaff in that wheat that you had to get through to make some sense of some of this. I am done with the covering but if it hadn't been for guys like Shadowrider and Harlan (FarmFox) who did a great job of showing what they were doing and sharing how it worked out after they started flying I am afraid my bourbon bill would have been much higher trying to figure all that stuff out.

alexM
01-29-2023, 11:04 AM
I have the bottom of my fuselage all webbed out with finishing tape everywhere fabric contacts structure.

Marcel Nölle just covered his series 4 at a Lanitz (sp? The Oratex factory) workshop. He saw my recent video and sent me a message about it. Apparently they say those tapes are completely unnecessary.

yocum137
01-29-2023, 12:05 PM
That’s the gist of what I just read in Lar’s Tips, too. Any place the fabric is glued down doesn’t need a finishing tape to reinforce the area.

Needless to say, I’m a bit put out finding this out now, after masking off all those areas and applying adhesive. No going back, now.

Oh, another Tip I gathered: 3:1 water and vinegar will remove unactivated glue. Pure Acetone will too, but there’s a better chance of damaging the latex* with it because most cheapo acetone contains other solvents (like MEK). 🤨

*Latex is one of the few materials that is resistant to acetone.

Geek
01-29-2023, 05:07 PM
The vinegar and water thing works awesome by the by. When I did the transition from the vertical stab to the fuselage and it required the finishing tape but you removed the glue from the tape and put the glue on the fuselage I messed up the layout of the glue and had to start over. The vinegar and water was really easy and was a no brainer.

G

Eric Page
01-29-2023, 06:27 PM
Apparently they say those tapes are completely unnecessary.
Finally, a reason to be happy that I've fallen behind...

yocum137
02-19-2023, 10:53 AM
Some of my own observations and tips so y'all don't go down the same path as me when using Oratex:

1) Get an IR temp sensor! Do NOT trust the temp of the Toko digital iron. It can be 10-15C off/high.
2) Use 90C for the initial placement of your finish tapes. Work out the bubbles and hold the iron on for 5 seconds.
3) Use 120C for the final glue activation of the finish tapes. DO NOT GO ABOVE 120C! Use your IR temp sensor to ensure it is NO HIGHER THAN 120C!

120C is the lowest temp the glue really activates for a good bond and the highest temperature you can use before the fabric starts shrinking. It's the sweet spot. You do NOT want your finish tapes to shrink and expose the edge of the glue you painstakingly masked off immediately prior. Once it's exposed and activated there's no way to get it off without damaging the paint and fabric.

If you have glue starting to squeeze out from the finish tapes at 90C you can scratch at it a bit with your thumbnail and it'll come off. But once it's cool, it's game over.

4) 90C for fabric applied to composite, i.e, the leading edge - fiberglass and carbon. 2 passes. 90C for 5sec and and again 90C for 10s. These are big surfaces and a lot of glue is holding the fabric on. It'll never come off.

Make sure you watch Harlan's videos on how to apply the fabric to the LE and follow that to the letter. Get get you a spouse/partner who likes you a lot and will stretch the fabric while you do the first pass.

yocum137
07-09-2023, 09:07 AM
I’m at the cowl fitting stage and the manual says “Temporarily bolt the cowling face positioning plate onto the prop flange.”

👀

What’s this “face positioning plate?” Is it something that should have been in the kit? Do I build it? Is there a template or blueprint of it, somewhere??

Thanks!

32658

Geek
07-09-2023, 01:19 PM
I’m at the cowl fitting stage and the manual says “Temporarily bolt the cowling face positioning plate onto the prop flange.”

👀

What’s this “face positioning plate?” Is it something that should have been in the kit? Do I build it? Is there a template or blueprint of it, somewhere??

Thanks!

Never saw one in my kit or a template. I used the backing plate for the prop spinner to set my forward cowling position.

G

Shadowrider
07-09-2023, 03:34 PM
https://lh3.googleusercontent.com/pw/AIL4fc_wh9LTlP869yPQ9RRLWBl6MUFv8WWKRwkLIKJaMaaRWe ZzvpwL_Rq5hR02G9B869qTb6GNHLSMVWOgpLtNLYB3QVA5LcRj XteTov7y2zzvaipyesQGxd9qd32SRZNXliNKFND9__d-gTLQVjcFcAqFIQ=w764-h1019-s-no?authuser=0

I think they are referring to something like this?

yocum137
07-09-2023, 03:58 PM
Yeah, that’s what it is. Did you build your own?

Just wished the manual said something like, “use the prop flange template, spacer, and spinner to build a positioning plate to create a 6mm gap between the spinner and cowl” before saying to install it.

Shadowrider
07-09-2023, 04:21 PM
Yeah I agree! Must be harder than you think to update the manuals? I borrowed one from a forum member. I will look but I think I have some other pictures on how to make one.

Kitfox Pilot
07-09-2023, 05:07 PM
Never saw one in my kit or a template. I used the backing plate for the prop spinner to set my forward cowling position.

G

I too used the prop spinner.

yocum137
07-13-2023, 08:50 PM
Mounting the cowl. Page 18 says to install the lower cowl for radiator fitting. The exhaust is pre-installed on the 915is and no clear direction on where to cut the hole in the cowling for the stinger to pass through. Yes, there’s a scribed circle on the cowling, but it’s not to be trusted so says the manual.

Page 44 finally gets around to cutting the hole for the stinger and says to use the radiator as a reference point.

Which came first, the chicken or the egg?

😳🙄🤨

Any words of wisdom? Harlan, what did you do, here?

yocum137
07-14-2023, 08:23 AM
I found the answer in Harlan’s videos (thanks again, sir!): remove the muffler.

Kitfox Pilot
07-14-2023, 12:14 PM
Just saw your post. Yes on removing the muffler.
Cut small and enlarge to fit when you do get to the exhaust hole.

yocum137
10-20-2023, 05:10 PM
Figured out a pretty good way to locate the hole in the cowl for the muffler. A 2x2 piece of cardboard with one straight edge to clamp/tape on the bottom of the radiator, even with the rear edge. Trace the outline of the radiator, cut a 6”x6” hole about where the stinger will come through, then cut a right sized muffler hole into a 9”x9” that can be taped down to the big template. Take off the template and cut where the front of the radiator is and line that up with the rear of the NACA duct and that’ll get you within a 1/2” of where the hole should be.

The pictures make it easier to understand.

https://uploads.tapatalk-cdn.com/20231021/72d1a79401fafe91e8948d2a2554d63d.jpg
https://uploads.tapatalk-cdn.com/20231021/7f0ba9c45489422050553dca7ff0a18c.jpg
https://uploads.tapatalk-cdn.com/20231021/9e06afb4c6f65e53ae9d11e367e786a8.jpg
https://uploads.tapatalk-cdn.com/20231021/926fcee646171e6c130934cf1c97f60e.jpg
https://uploads.tapatalk-cdn.com/20231021/db4b0475bb49667696410ad0a9936c62.jpg
https://uploads.tapatalk-cdn.com/20231021/66599c47cef163bdc0fc3106310cfaed.jpg
https://uploads.tapatalk-cdn.com/20231021/a1cba08dba6ce40f36f6733379a3b2ad.jpg


Sent from my iPad using Tapatalk

bbs428
10-26-2023, 09:48 AM
That carbon cowl looks great. The exhaust hole lined up well. Bet your glad you don't have to fix or re-do that cut!

The cowl fitment portion of the build sucked a lot of life out of me as it has to go thru dozens of fit and cut cycles.

Yours is looking real nice!

Kitfox Pilot
10-26-2023, 10:35 AM
You came out really good on your muffler hole but you will want to enlarge it a good bit.
Those engines move a lot. I retrimmed mine twice after installing. They move down about a thumbs thickness. Not hardly any up movement.

yocum137
10-26-2023, 05:44 PM
Yeah, Brandon warned me that 1/2” (like the manual says) wasn’t enough when I saw him a couple weeks ago. 1.25” all the way around - about 2 knuckles width.

Once I figured out the template it just fell into place - one shot!