To weld, or not to weld, that is the question!

Over the years, I've had numerous setbacks in this project. In 2004, I bought my core engine (Corvair) and started having parts converted for flight duty. Back in those days, that required local machine and/or auto performance shops to do work to William Wynne's (FlyCorvair.com) specifications. Over and over again, my local machine shops would do things differently than was specified, or would simply not do things at all. With all the problems, long wait times and supply problems, I had all but shelved this project. In 2011, I committed myself to building this aircraft. Another 2.5-year hiatus, and I'm back to building as of July 2015.

Recently, I had an agreement with a local welding shop for my aluminum fuel tanks. Welding aluminum requires AC TIG welding, a process that is both difficult to do well, and hard to find professionals willing to do it. My local shop looked over my blueprints back in August 2015. We discussed the liability issues and FAA regulations. They agreed to weld my tanks up once I had them fabricated. Fast-forward to January 2016...I had the tanks fabricated and ready for welding! I took the tanks in for the job, and they promptly turned me away. The owner of the shop either forgot he had spoken to me back in August (not likely), or he decided the job wasn't worth the effort or liability.

Disheartened, I looked for alternatives. I decided to purchase welding equipment, spend the next 6 months learning to weld while working on my plane, and then weld the required structures myself. After a lot of research, I decided that the 2016 AHP AlphaTIG 200X AC/DC Inverter hobby welder would suit my needs. It arrived yesterday! Check out my video below as I detail the equipment required to weld my airplane, along with my rationale for learning to weld and doing it myself:

I broke the brake, which broke the bank...in the process I broke my back (j/k)!

Well, I've had a few discouraging moments lately. I was attempting to bend up some .063" parts on my DIY brake. The smaller parts went fine, but when I tried some of longer bends (around 900mm), I strained my brake too much and the rivets in the piano hinge started pulling out! Here's a video where I talk about my woes:

Buying Metals

A question came up recently about where I source my metals. There's no easy answer to that. Metal prices vary widely between vendors, and prices can change significantly with market fluctuations. I've ordered/purchased materials from just about everywhere, but my usual locations are Zenith Aircraft (they sell raw materials directly to scratch-builders, unlike some other kit manufacturers), Aircraft Spruce & Specialty, Wick's Aircraft, Alro Steel (locally), Amazon and even eBay.

The major surprise was Amazon.com. Lots of materials vendors on Amazon have random cut-offs of materials that are perfect for some of the smaller quantities I needed in the plane. I ordered everything from .090", .125", .1875", .250" and .500" in 6061-T6 aluminum in the small quantities at very reasonable rates with free shipping on most of them. Because I have an Amazon Prime account, I got free 2-day shipping on a lot of it. I can also order the 4130 chrome-moly steel I need from Amazon in some cases, though the prices are not as competitive as with the cut-offs of aluminum.

Anyway, it pays to shop around. Make sure you're getting competitive prices, do your research and don't forget to have them "roll for shipping" the larger 4'x12' sheets of aluminum up to .032" thick. You can even negotiate prices with some of the local dealers. Here's video where I talk about sourcing metals:

Staying organized with a builder log

All of us who build our own aircraft are required to keep a builder's log with information on our progress. The FAA doesn't really specify any particular method or format for the builder log, but generally you need to keep photographs of your progress and some sort of narrative detail. I didn't like any of the pre-packaged methods out there, so I ended up creating a spreadsheet in Google Sheets. The nice thing about Google services, is that everything is seamless and automatically backed up. Since I use a lot of their products, it only seemed natural to use their spreadsheet. In the video below, I talk about my reasoning and methodology for my builder's log, which consists of this online blog and my spreadsheet.

The cabin is starting to take shape!

Well, I was hard at work yesterday for most of the day. Got the cabin side skins cut, and decided to start match-drilling the skins to the support angles. I previously made all the 3/4" x  3/4" x .125" support angles that make up the skeleton of the cabin side. The plans call for this angle to be .093" thick, but that size is a custom extrusion for Zenith Aircraft, and is very expensive. The alternative is to use the commonly available .125" thick angle. There is a 2-3 lb. weight penalty by using this thicker material, but it is stronger and way cheaper.

Angles for Cabin Frame (Longerons, supports, etc.).

Cabin Side Skins (these took a few hours to measure and cut):

Pilot Cabin Side Cleco'd together!

More to follow!

Making more of Zenith's "Standard L"

So originally, I wanted to make Zenith's Standard L angle as I went along the build. However, once I started making it, I really got into a groove, and after about 12 hours (total across 3 working days), I had 64 pieces fabricated. Making Standard L is a long tedious process, but all of us Zenith builders who are working from blueprints only (not a kit) have to fabricate it. It is $7.10 per piece if you order it from zenith. At 64 pieces, that's $454.40 for all the Standard L you need in the plane. 64 pieces of L equate to about 3/5 to 3/4 of a 4' x 12' sheet of .025" aluminum. At current market price, a full sheet of aluminum is only about $100. So you can see the savings, but it costs you time. No matter...3 evenings of making L and I saved nearly $400! Hooray for plans building. Here's a video where I talk a little more about making Zenith's Standard L.

Some Tidbits in .025"

Well, I've been putting in a lot of time cleaning up odds and ends in preparation for assembly. Trying to decide where to start is the hard part. I've finally received my rivet gun and also picked up a nice high-speed pneumatic drill. The rivet gun was necessary, the pneumatic drill will make drilling the thousands of small rivet holes go much faster. With high speed drilling, I get a lot less burrs on the holes to clean up before riveting, saving tons of time. Last night I started the process of making all the "Standard L" angle that is found throughout the plane. For Zenith scratch builders, this is a well-known, dreaded chore. Zenith calls for roughly 64 pieces of "Standard L," which start life as a 4' pieces of .025" L-angle, 19mm x 19mm. They then get cut to length as needed in various substructures. The way to make them is simple, cut 36mm strips of aluminum off the end of your 4'x12' sheet, and bend them lengthwise down the middle. OVER AND OVER AGAIN! A simple enough task, but tedious. You have to de-burr each piece before you can bend it. Measure, cut, de-burr, bend. Wash, rinse, repeat...

24 pieces of "Standard L" that I made last night (8 additional pieces from a previous day not in the picture...32 to go!):

End view of "Standard L"...not much to it!

On a more fun note, I also started working on the "options" for the plane. Zenith charges $150 for the drawings of their options, which include things like sliding adjustable seats, center console, folding wings, dual control sticks, long range fuel tanks, etc. I'm only going with the sliding seats, dual control sticks and center console. $150 seems pretty steep to me for only a few drawings, but intellectual property is worth something, so it is what it is.

Center Console (this goes between the seats and just under the instrument panel. It will hold things like my fuel tank selector valve, phone charging ports, intercom/headset connections, flap controls and a few other bits):

Top Window Ribs, Door Sills and Center Arm Rest:

That's all for now. I'm working on a detailed "developed length" video as a replacement for the one I deleted from a previous post. Developed length is one of the most challenging aspects of building from scratch, and, as I've already talked about, can ruin a lot of parts if you don't do it correctly.