The glorious smell of heat treated steel.

Builders,

I pulled in my driveway after dark yesterday and saw four cardboard boxes just sitting there. I soon found out why my ups driver didn’t carry them to the hangar: they weighed about 50 pounds each. A quick check with a flashlight reveals joyous news; A three year supply of hybrid studs had arrived!

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Above, the boxes in my living room. When I opened them, the oily smell of serious old school machine shops filled the room. The studs are made from heat treated 4140  us steel, the same as WWII .50 BMG barrels. The smell brings me back to my youth in NJ, some of my first jobs working in the remnants of the state’s once thriving machine parts industry. As a Corvair builder, you can have a certain pride your CEO here is sipping a beer, listening to Check Berry and savoring the smell of heat treated steel.

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The studs have always been made for me in a giant midwest machine shop that specializes in aerospace fasteners. They don’t do small orders, so once every 30-36 months, I empty my piggy bank and send in an order. A few months later, their arrival comes without announcement. Insisting on ‘Made in America’ from serious suppliers isn’t cheap: The stack of four boxes cost more than my last two pickups, and my Suburban…combined. Carrying this kind of inventory on an engine program known for being inexpensive is tough, but when it comes down to the fasteners which hold the prop hub on, if you understand strength of materials and ethics, you don’t go shopping in China.

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Wewjr.

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Time to change two heads around

Builders,

In the previous story; Photo Observation Contest., most people quickly picked off that the assembled engine had the heads on the opposite sides of the motor. The second question is how long did it take to correct this?

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There were a wide variety of estimates, but first lets examine a few fun internet myths;

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On a car, the heads have the same casting, but they are not really interchangeable right and left. The reason why: there is a 3/8″ diameter breather tube in each head just below the stock carb flange (these are machined off when we weld head pipes on) both of these tubes point toward the flywheel in a car. The are hooked together to for a balance tube and the PCV system in the car. It is common to see people building a car engine forget this, because it is less obvious than a welded on intake.

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Second, I was always amused to see people who claim to be very experienced engine builders on the internet, when seeing a report of a temperature variation on left and right banks of a flying Corvair, quickly pontificate it must be the engine is somehow using two left or two right heads. The Corvaircraft internet group archives have numerous examples of this. Of course its moronic because the castings are the same L and R.  This isn’t unique to Corvairs, virtually all classic American V-8 and V-6 engines, including diesels, use the same head on both sides, but this basic fact wasn’t known by a lot of internet experts.

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On the subject of reversing the heads on the motor shown, there was a little more involved, because if you look close, the rockers are already on and the valve adjustment is already done. This in mind, the task breaks down into several group tasks:

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Remove the rockers, balls and pushrods from both sides.

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Un-torque the heads, lift the push rod tubes, and lifters.  Remove each head.

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Reposition the engine on the stand with the head facing up. I do this because I don’t like torquing heads with the engine on its prop flange or with it in the installed position if I can avoid it.  Not only is it simpler to work on in the 90 degree bank flight position, it keeps assembly oil from the cylinders from flowing under the head gaskets before they are fully torqued.

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Reinstall each head, and torque it into place.

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Reinstall the valve train, and reset the valve adjustment.

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750 Builder Lane Seidel, Barnwell College regular.

Builders,

Below is one of my favorite photos from Corvair College #43 at Barnwell last month. It is Lane Seidel’s shirt, with several of his name tags from previous colleges. He is holding his phone, showing a picture of his nearly done Zenith 750 STOL, and yes, his engine was first run at a previous Barnwell college.

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Ask anyone who has met him at a College, Lane is the best sort of guy, easygoing and laid back. With his southern accent, it is all pretty good camouflage for a highly accomplished, but modest man who works in nuclear power.

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If you want to know what makes him invaluable in my book, a story: At Corvair College #34, also at Barnwell, a builder had a crippling medical emergency. You can read some of the background here: Builder Medical Emergency Update. The onset of the man’s crisis was hard to see in the bustle of an on going college. The moment of awareness of his emergency comes from Lane, coming over and telling me he thinks the man has a serious issue we are not seeing. Minutes later we are traveling to Aiken Hospital, and the staff later tells me we cut it pretty close. There were many other builders who later put forth a very strong effort on the man’s behalf, including many people who contributed to a fund which topped $10K. But without Lane, who not only had the observation skills, but also lives by ‘I am my brothers keeper’ instead of societies all to common, ‘I don’t want to get involved’  we very likely would have lost the man.

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Wewjr.

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Photo Observation Contest.

Builders,

Just for fun, see if your observation skills are sharp. Study the engine photo below and see if you can find the detail the builder initially missed on assembly at Corvair College #43 earlier this month.

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The issue was corrected, and this engine put down a perfect break in run on my stand at the college. Use the comments section if you think you see it. Bonus points for the closest guess in minutes for how long it took to correct.

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WW.

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New Nose Bowl Plug – #4201-B

Builders,

Here is an update on the story of my new nose bowl for STOL Corvair powered planes. This is the original story from seven weeks ago: WW- ‘STOL Bowl’; A new nose bowl available this month, Pn. #4201-B.

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In the original story, I projected having completed parts on hand by now. It was reasonable from speaking with my mold shop, but there have been delays on his end, and we are just getting to the molds now. I have known him and worked with him for more than a decade, he is pretty good on timelines, but not in every case.

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I deal with it because his quality is good and the work from his shop is a good value to homebuilders. In my last 29 years in business, I have dealt with many suppliers, and have always sought out quality, and accepted some delays to get it. The new projection based on today’s face to face meeting in his shop is 3 weeks to deliverable parts.  I’m a little too old to believe in Santa, but still optimistic about what I want for Christmas this year.

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Above , a view of the topside of the finished plug, the inlets have built in rings and are more than 5.5″ in diameter.

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Above, a view of the bottom of the new plug. It has been check with elaborate contour tooling, it is polished next in preparation for making the molds from it.

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A look at shop parts and work.

Builders,

Below is a picture of parts which came in this week, which are part of the steady flow of work in my hangar. The represent three elements of a typical work week.

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On the left, CNC machined stainless steel exhaust stacks, the basic element of all the Corvair exhaust systems I have made in the last 15 years. (Stainless Steel Exhaust Systems) The same aerospace shop in Florida has always made these for me, and they like to make them in quantity. They start as solid American 304 stainless bar stock, and they are not cheap. The bin pictured has over $7,000 in parts in it. Over the winter, I will weld these into many exhaust systems so we start the 2019 season with a lot of systems on the shelf.

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The four Gold oil filter housings look common to our engines, but if you look close, they are 2601-R models, the “R” designation is for ‘reverse’, they are the mirror image of our standard part. The only common use for these are Corvair/Sonex installations. Look at this picture: Waiex engine, 3,000 cc / 120HP Corvair of Gordon Turner. , and you can see the difference. These also have to be made in batches, and I sell about 20 times as many standard ones, so I only order the “R” model once a year or so. Even though it is a small part of what we are doing, I still invest in the parts to make sure every builder can have an optimized engine.

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The last part is a Dual points distributor I sold to a Pietenpol builder in Australia…..about 15 years ago. It has been flying a while, and it has just come back for a check up. Think of it, its logged about 22,000 miles aloft. Its the kind of thing a do nearly every week to support a fleet of 500 or so flying corvair powered planes. If your out in your shop working tonight, don’t worry, in another 15 years I’ll be here for you also.

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Ongoing Carburetor testing.

Builders,

The previous story covered updating the aluminum pushrod tube installation in my own personal Corvair engine. This was half of a particulars day of testing. The other half was to run the particular NAS-3A Stromberg carb pictured below. It has a different set of jetting in it, and we are working to fine tune it, and add that set of data to our carb knowledge.

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Strombergs are a traditional carb, not only for Corvairs, but for US light aircraft in general. The have a long track record of very good service. The particular one has a variation on what we have previously done before, and thus a test run was in order.

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Above, freshly overhauled Stromberg, running on my 3,000cc Corvair. The Fuel filter is an Earl’s unit available from Summit Racing, it has an accessible element and -6 AM male fittings on each end. My test stand has had one for years, and I also have one on my plane. Be very careful not to install it in a plane in a position where it could trap water.

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The photo doesn’t quite capture it, but the jetting or setting was on the rich side. Under some circumstances, it was producing visible black smoke. Look at how dark the tailpipe is. Keep in mind this is running on pure unleaded car fuel.  The Exhaust piped on my test stand have had 18mm threaded ports in them for the last 10-12 years, and I have used them with a wide band O2 sensor to know the actual air fuel mixture going to the engine. That is the next step in gathering data here.

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This was the afternoon on November 17th at our airport in Florida, still pretty green down in the sunshine state. The season slowing down with the approach of the holidays and the arrival of cold weather up north, we will have many afternoons to test ideas and parts in the coming months.

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Wewjr.

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