Silver Grrlll

Next, PolySpray, an aluminum pigmented solution to block UV from weakening the fabric. It settles in as little as one month, so you can imagine how it looked after 10 years sitting in various hangars. Luckily, it doesn't deteriorate in unheated hangars like paint.

 

I had bought some 8500 reducer that was for use in temps above 85F, we were having a heat wave and it was a perfect time to use it all up. You have to reduce the PolySpray 4:1, and for some damn reason I could not find an empty gallon can in town, so I ended up using a couple quart cans. Sure hope I did the math right. 

Testing, 1, 2, spray.

So far, the Sharpie is not bleeding through.

They say the silver coat will show every flaw, every imperfection in your work. They're right. I found some hangar rash after the first coat, and spent an afternoon sanding down stuff. At a certain point I had to call it Good enough, and accept that it will not be a flawless finish. Some pieces are pretty good, some are OK, I'm happy.

This was probably my biggest Oh shit moment. In the middle of the night Jim texted me that the solvents in the Spray would probably life up some of the tape edges, he was right. I went too slow with the iron, and even through a piece of butcher's paper I melted the coatings. Reducer, patience, a titch lower heat and quicker movements of the iron made it go away.

Don't run. Don't run. Don't run. Don't run. (It didn't.)

Despite all my best efforts, some of the tape edges still refused to lay down. Well, they're not really lifting up, they're just not smoothly flat.

You're supposed to put a 60W bulb inside the wing and check for the light to shine through, if it does you need more silver. (so THAT'S what that caged worklight on the wall is for!!) Can't get a bulb inside the control surfaces, so when I get home I'll have to settle for shining it from one side to the other. If it shines through 2 layers of fabric, 6 coats of PolyBrush, and 12 coats of PolySpray I really got problems.


I'm hoping to alternate painting and trips in September. Next week I'll come home, paint the control surfaces (major gulp), and prep the fuselage (fin, rudder, metal pieces). Go on a trip while the feathers are drying, come home, move the fuselage to the paint shop and bring stuff back to the nest, PolyBrush and Spray the fin/rudder, go on a trip and let them dry, come back and paint, go on a trip while it dries, swap the wings and fuselage, and you get the idea. In a perfect world and if everything goes right, she'll be all painted in September.



But you know the saying: Man plans, God laughs.

Pretti(er) when Pink(er)

With work on the avionics well underway, the long pole in the build has become painting. I was supposed to have it done earlier this year, but when the painter saw I had not Read The Manual (RTFM) and used a Sharpie on the covering, he refused to proceed since Sharpies will bleed through. I halted painting and stewed about it for a while, trying to decide if I wanted to do the smart thing, stip off all the covering and redo it the way I should have, or go ahead and paint anyway, knowing the Sharpie was going to bleed through. After a while I realized that if it bled through, I could alter the design and cover the marks with the vinyl from the design, so I contacted my painter and gave him the go-ahead. Unfortunately, my painter had moved on to other projects and was now backed up for months with work, but we worked out an arrangement where I could use his paint booth and do it myself. *gulp*.

Step 1: Moving and cleaning.

My friend has a REALLY nice paint booth, first step was to give it a good blowing and vacuuming.

It's been so long since I put the first coat of PolyBrush on, some tapes had lifted and needed a touchup with the iron.

In other places the boiled linseed oil had seeped through rivet holes and also needed a wipe with MEK.

Then there were the Sharpie marks....

First, some practice. Long time ago I had built a couple 3x4 practices pieces out of PVC pipe and leftover fabric, now was the time to put them to use. I've used a gun before, so it was a matter of knocking the rust off my spraying technique.

Intentionally, I sprayed too much into one area and made it run so I could practice fixing it, for when it happens on the real control surfaces.

Trying to get that "just enough to cover but not so much it will run" amount.

But before we started spraying, some 1/4-28 threaded rod was cut down, honed,

bent into hooks and threaded into the nutplates for the hinges.

This time, I RTFM'd the manual and caught this little gem at the end. It's been about 7 years since I covered the last piece, so it's a good thing I saw this.

If in doubt, write it out.

Sludge, sludge, everywhere. Good thing there's a paint shaker to spare.

Here's why I made up the hooks. A forest of control surfaces ready to be painted. I'm going in.

shit shit shit shit....... This is not a drill. Happened more than once, less than a lot. Was able to fix each one, whew! (It's not if you make a mistake, but how well you can recover from one.)

Some tapes started peeling up, you didn't want to use the iron much, best to use it through a piece of parchment paper.

No matter how careful I was in the prep, there were still dust/grit/whatever on the control surfaces. You could not see most of them, but they felt huge when I ran my hand over them. How big is too big? I knew it when I saw it, and took the time to iron or peel off the ones that would come off easily. Time will show how bad they are, but... this is not my umpteenth airplane build, and I'm not going for a Lindy award at Oshkosh. This caged bird ain't singing, Osp wants to FLY!!!!!

Bits and pieces

The new Dynon 160 label maker came (as suggested and reviewed in Kitplanes), I had drug my feet as long as possible because the old one used 1/8" heat shrink tubing, but all I could find in the new one was 1/4". Turns our they're both the same size, somehow, and the 1/4" fits fine.

As did the new, smaller LED indicator lights from Oznium. With the bigger, more aesthitcially pleasing lights I have to add a 10k ohn resistor to balance between an acceptable level of day and night brightness, but the smaller ones have the resistor built-in, and a colored lens to show up better.

But, frustratingly, the 2 piece connector I got is too big to fit through the 8mm hole of the smaller indicator. Going to put that in the "Step away and think about it." pile while we move on to other things for a while. 

Opportunities come from misteaks.

With all the puttin' together and takin' apart I accidentally broke the connector to the Dynon Skyview backup battery. But... in my search for a replacement, a light went off and I thought Hmmm.... if that carries power from a battery to the Skyview, then it should be able to carry more than enough power for a LED. Looks like the OAT sensor uses the same type of connector, and it looks like it would fit in an Oznium 11mm LED sized hole.
 

Yup. Kewl. 

A quick post on the Dynon forum yielded the part number for the OAT sensor connector, a followup call to Mouser yielded the part number for the 3 hole backup battery connector, turns out they're rated for 5A, 600V. Hot stuff, they'll be here Friday, in time for some good weekend work.

 Best part, they're only $0.32 each. Whoo-hoo!!

Blinded by the light

Now that we're working in the front avionics compartment again, I was reminded of an old saying that goes along the lines of "Sure, you can install it, but can you fix it once you install it?" With that in mind a quick fit check to make sure that I could get to the stuff I'm now working on. Yes, I do have access. All is well.

During the Quest for the Perfect LED Indicator, I came across some lights by Oznium. Aesthetically, they were very nice. But they were blindingly bright, even in daylight.

Oznium suggests I put a resistor in the circuit to lower the voltage and dim the lights, I checked with Rotax, Dynon, and ACI, and all said it was Ok to put a resistor on the ground/return side of the LED in their systems. Since the gear lights all hook into a common, pigtailed ground that was a perfect spot to test.

A dsub connector made the pigtail removable.

And connectors on each side of the resistor made it plug-n-pray. A gent on VAF had the same problem as I did and suggested a 10k ohm resistor. My first try was discouraging because I used a 10 ohm resistor, it was kindly pointed out that I missed the size by a factor of K. (Missed it by THAT much.)

Huge difference when you use the correct size.

Still a little brighter than I'd like for night flying, but I won't be doing a lot of that, and I can live with it.

...