Debate about Mark Langford's 3rd crank failure

Discussion in 'Corvair' started by Will Aldridge, Jan 23, 2012.

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  1. Jan 27, 2015 #161

    Autodidact

    Autodidact

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    I think you're building a bogeyman in your head. I don't think anyone here is against Corvair engines. As for how many Corvair builders there are here already, you want more of them don't you? Welcome us to your world instead of trying to exclude us with the "six questions" barrier.
     
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  2. Jan 27, 2015 #162

    BoKu

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    Yes, Mark Langford's at Columbia CA (O22).

    Yes, Mark Langford's at Columbia CA (O22).

    Are any of those questions relevant to a simple question about bending and modulus of elasticity?



    The project is going well, thank you, but that is completely irrelevant to the issue at hand. My interest is in sport aircraft development in general, and to the best of my knowledge that is qualification enough to participate here.

    The question was a simple test to see whether you would address the message or the messenger.

    Thanks, Bob K.
     
    Last edited: Jan 27, 2015
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  3. Jan 27, 2015 #163

    Kyle Boatright

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    William, many of your posts on this site and your blog are anecdotal in nature. We're here on a Homebuilt site, looking for data, answers, solutions, and new ways to go about things. The level of technical expertise here is impressive, and the experts are largely focused on data. That doesn't indicate any bias for or against Corvairs, but when a Corvair expert begins offering opinions on the engine in aviation applications, certain questions are likely to arise that would best be answered with data instead of anecdotal evidence.

    As an example, in your blog, you repeatedly identify Chinese manufactured components as "junk". Maybe they are, I don't know. But I'd like to see some sort of objective measurement against a defined specification before relegating something to "junk" status. Is the material sub-par? If so, provide some data as to why. Alloy? Heat treatment process? Maybe the dimensions don't meet spec. If so, I'd like to understand the specifics. It is far easier to accept "We sent an XXX Chinese crank in for testing and here is the certified lab report showing the mains were misaligned by XXYY, and...." than to simply accept the broad brush statement that "Chinese cranks (or rocker arms, or whatever) are junk."

    In the discussion with Ross, you wrote:

    "My point was that yes, the loads can be determined, but there are variable on how individual engine assemblies that are built by amateurs of parts reconditioned by various vendors can take these loads. Also, a very smooth pilot can have a very different set of loads than one with harsher inputs, particularly in aircraft with light controls. My point is that the engineering model has a hard time evaluating these other variables."

    My thoughts are that we're trying to evaluate the suitability of the engine, not the pilot. It is possible to determine the structural limits of an engine (or crank) built with your recommended procedures and components. Following that, the obvious thing to do is measure or calculate the forces involved in various phases of flight to establish recommended limits - RPM, "G" onset, prop moment of inertia, whatever, so no component of the engine is stressed beyond (or close to) its limits. Ideally, that would allow Corvair flyers to have confidence in their engines within a clearly defined operating range.

    To some extent, Bob K has already addressed your "6 question" approach, but I'll go one step farther. I much prefer fact based answers to questions. For instance, regarding TV: "We haven't had the funding to do TV testing on the cranks, but here's our experience and history that relates to the issue:" is an answer to a TV question. "Can you answer these 6 questions..." isn't an answer. It is anything but an answer.

    Respectfully,

    Kyle Boatright
     
  4. Jan 27, 2015 #164

    mcrae0104

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    Pardon me for quibbling, but perhaps by "on the scene" you meant "posting on HBA." Otherwise, the reverse is the case. See here, paragraph #1. You are certainly correct that Mr. Langford is modest. He is very unassuming and still quite an ambassador for the Corvair movement. That alone should really give skeptics something to think about. I'm really not surprised he jumped in briefly and has stayed out of this thread (indeed, the whole forum) since then.
     
  5. Jan 27, 2015 #165

    rv6ejguy

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    William, you chose to jump in here, addressing an old thread and as previously mentioned by someone else, this can be a hard crowd and there are some very smart people here.

    People here on HBA are very open minded to auto conversions compared to many other forums and the Corvair is often mentioned as a possible choice to power a new creation. Nobody wants to see you fail but they are interested in direct answers and the reasons and story behind those answers.

    Your first paragraph deflects and tries to change the subject. My post was about TV primarily. TV does not care about pilot input and it's a well understood science. I agree that flight time does prove the overall system, but several thousand hours collectively over a a few hundred engines is no substitute for scientific evaluation. Despite what you say about valuing engineering and science, you still appear to discount it by saying you know best.

    Your second paragraph avoids answering my simple question about hours flown. Can I assume that no Corvair has accumulated 2000 flight hours without problems then? I picked that figure as a standard TBO period for small Lycoming and Rotax 912 engines although the O-235 has a TBO of 2400 hours now I believe. I can think of Rover, Ford and Chevy V8s which had well over 1000 hours of flight time on them with no problems or crank failures. I can think of thousands of Subaru engines with many hundreds of thousands of hours of flight time on them collectively with the high time one I know of with 3800 hours on it without going inside it. There were over 650 RAF gyros produced with Subaru power alone. I can think of thousands of VWs flying worldwide as well for many decades now. I've been involved with auto conversions as a component supplier for over 20 years so I get a lot of feedback from customers flying many different engines all over the world. While your recent success is encouraging, the flying Corvair cross section is minute by comparison to these.

    My point about the crankshafts was that the nitrided 140/180 cranks were readily available and known by Corvair engine builders decades ago to be far superior in fatigue resistance to the 95/110 cranks. I just don't understand why people would not always use them for an aircraft application. As I said in another thread, these cranks rarely need regrinding in the first place because they are so hard. As a race engine builder where I pay great attention to detail, I never reground cranks and was well aware of fillet radius importance. This seems to have been discovered by accident if you'll pardon the pun. It hardly seems to make sense coming from an authority on Corvair engines.

    You seem quick to dismiss Mark's experience as invalid with other flying Corvairs. Perhaps but also perhaps not. I'd be inclined to be open minded and try to learn something from it. Personally, I think Mark's decision not to fly another 8409 crank 3100 is pretty rational.

    Some more information which others might consider useful regarding Corvair engines, this coming from my good friend who is one of the most experienced and respected Corvair performance engine builders in the US- "Years ago it was uncommon for a crank to fail mag, now I am finding about 1/3 of the cranks show cracks. Most common is between the #5 and #6 rod journal, but I am also finding some between the #1 thrust and #2 rod.


    Last year about 1/2 of the cranks I had mag'ed were cracked. Maybe this was an unusual year, maybe it is going to be the norm for now on. I do not know, but will let you know in December. :)


    I have not noticed a significant difference in the failure rates between the factory nitrided cranks [140 and 180] and the non-nitrided cranks, but my sample size is too small to make any valid conclusions. We also have into play that very few standard cranks are still around so any 140/180 crank which is ground is no different than any other non-nitrided 1964-69 crank."

    Lesson- all cranks need to be mag'ed, grinding without re-nitriding is a bad idea. We all knew this in the Corvair world 30 years ago. I owned my first one back in 1978 and built many engines for street and race use- up to 350hp turbocharged. The knowledge was out there long ago.

    A good engine builder knows a lot about details and checks everything the machine shop touched prior to assembly to give the best possible reliability on the finished product. Of course we all learn new things as we go but I believe a modest, open minded and humble approach sits a lot better with with most people than saying we know it all and then have failures.
     
  6. Jan 27, 2015 #166

    William Wynne

    William Wynne

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    Mr Boku

    I have been pretty close friends with Mark Langford since 1999, and in the years that his plane N56ML was flying, I covered most of his travels on our website. The plane was operational from 2005 -2011, and the whole time it was flying it was light tan colored primer. It logged 1130 hours. I spoke to him on the phone a hour after the first flight, I was flying beside him when he logged the 1,000 hr.
    ..
    I am pretty darn sure the plane was never very far west of the Mississippi River. If I am reading your comment post correctly you are saying that you saw N56ML in California? You are sure of this?
    .
    Mr Boatwright:

    Please get a look at the pictures on this post about a Chinese Corvair Crank that failed in 40 minutes of ground running turning a Sensenich 54 x 56 prop on a 2700 CC Corvair: Chinese Crankshafts | flycorvair Look at the second photo down, and you can clearly see that the crank came straight from the Chinese factory with a hidden repair on the output end of the snout, where it was cut down to a very thin section, and sleeved, and this was hidden under the shrink fit hub. I did not think that I needed to test the alloy to decide that this was not a good supplier.
    .
    Over last summer, two builders using rocker arms supplied by Clarks Corvair parts had them fail in flight. Neither aircraft was damaged. Because we were returning from Oshkosh, I released this alert from the road without pictures: Safety Alert: Chinese Rocker Arm Failures | flycorvair The rockers from Clarks had originally been supplied by Pioneer, a North American brand. At some point Clarks had quietly switched to Genuine Brand, a Chinese supplier. One of the builders with the failure was Andy Elliott, who holds a Phd in Aerospace Engineering from MIT and works daily in materials and structures. He offered to run all of the samples through his metals lab, and the primary issue revealed in the Chinese part was they were less that 50% of the thickness in the ball area, where the failures happened. I did not test the hardness, as we determined that they were not correctly formed, precluding their use.
    .
    It used to be quite common to reverse rotate Corvairs. When this is done the distributor still turns the same way, because it has to run the oil pump. The bronze gear on the crank and the steel gear on the distributor are changed to allow the crank to turn the other way, while retaining distributor rotation. The gears were made by OTTO parts in CA for many years. In 2011, they were switched to a Chinese supplier, without notifying buyers. The first two engines built showed extensive bronze in the oil on the ground run. When the distributor was pulled, the shaft was blue from heating and bending, because the gears were not dimensionally correct. Several more sets were test fit with the same interference, this was directly compared to California gears on the same engines. The supplier declined to recall the gears or remove them from the catalog. This story is well covered in our manual. I have many detailed stories like this,
    .
    Perhaps you will see these as data? Hopefully you do not consider my observations on these just anecdotal and not valid. The pictures on my website have been there for many years, I did not just tell people they were "Junk". When a part is broken in a spot where I never saw a break in a stock part, even a very used one, and in the area of the break it is less than half the thickness of the GM part, and I do not make nor promote the part in the first place, I don't think I need to go to the extent of paying for a full laboratory analysis before telling our builders "Do not use these, the stamping is not correct, it is too thin in the ball area."
    ,
    Here is your "Fact" TV statement: "Since Corvairs are built in many different displacements, with and without 5th bearings, some with starter rings in the back, some with balancers, these balancers can have 2 different elastomers, people have used several different prop extensions, spinners and at least 30 different props, and I do not control through a certification or inspection process which combination builders elect to use, I could not afford the expense of measuring all the different permutations possible, and still offer an affordable engine. So we did not test them to FAR 33 standards, we just flew the combinations that I though best on our own aircraft, and them offered them as recommendations."
    .
    Mr Boatwright, I would like to know, in your personal opinion, if the owners of the aircraft I put in the links on the flying planes page are fools for flying in their planes without elaborate TV testing of the engine /prop combination they are using, or are they making a reasonable choice for themselves? Would you personally fly in any Corvair powered plane that did not have a TV analysis done? Would you fly any homebuilt with any power plant, that did not have this done? _ww.
     
  7. Jan 27, 2015 #167

    BoKu

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    I was pretty sure an hour ago, but looking at Mark's site, his airplane does look like a different KR than the one I saw at O22. So on reflection, you're almost certainly right. I don't know how I conflated the two; perhaps Mark's name came up in the course of conversation with the owner and was the one that stuck with me.

    Regardless, whether or not I've seen a Corvair-powered aircraft is pretty much irrelevant to the discussion at hand.

    Thanks, Bob K.
     
  8. Jan 27, 2015 #168

    William Wynne

    William Wynne

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    "One of the most knowledgable and friendly aviation discussion groups on the internet"

    That comment is in the title block of this forum, (with the misspelling), and I guess it is for each of us to decide how close it comes to our understanding of that statement, and then if we wish to participate or read it. While obviously many people have great expertise in particular areas, the thread here is about a Corvair, and I still think it is important to know how " Knowledgeable" a commentator is on the subject engine. As for the friendly part, I don't see asking people to specifically state their personal experience, not as a precondition to commenting, but as an addition to it, as unfriendly.
    .
    The previous post from Mr. Boku is a good example of why this is has value. If I didn't ask, Mr.BoKu would have continued to make his observations on Mark Langford's issue in the honest, but mistaken belief that he had actually seen the aircraft before, and spoken with Mark. Having done so is not a requirement for commenting, but perhaps we can agree that any impression Mr Boku may have acquired in observation could be revised with the understanding that he had not actually seen the plane this thread is about nor met the builder.
    .
    There is a lot of information on the net just on the subject of alternative engines, and I will say that I have met many of the commercial providers over the years, but other than on my own engine, I don't keep accurate track of the chronology of who developed what element. This is OK, because I don't offer evaluations on engines like Subaru's or VW's. Yes, I knew Art Beers and Spent time with Hugh Beckham, Who have been purported to be the first people to fly a Subaru and a VW in America respectively, but these engines are not my focus. You can learn stuff from them, and I have but, I understand that any fan of these engines could quickly show I don't know the chronology of who developed them.
    .
    That is why I have little issue with Ross saying " Before you were on the scene though, Mark was on the bleeding edge of flying Corvair engines and putting on a ton of flight hours quickly and documenting his trials and tribulations in a modest, informative and readable fashion." As another writer pointed out, It states on paragraph #1 of Mark's website that he was going to use a type 4, but switched to using a Corvair after attending a forum I gave at SnF 1999. Mark's site also shows that he came to Corvair College #1 as an observer, attended #2, and got his engine running at #3. The point of this is not to illustrate that I had been doing this for 10 years before Mark met me, the point is that the title here is about Mark's crank, and Ross states that he read Mark's site for information, but perhaps not as closely as he thought he did. And I think that is a valid point to make when we are speaking of looking at a mechanical event like a crank break.
    .
    Our Moderator in the Netherlands pointed out that the price for a full TV analysis is 25K. These is nothing in the economics of teaching people how to build Corvairs that would remotely allow this for each Corvair combination. I have never stated nor implied that we have done this, and our builders know this. Mark Langford works to Teledyne Brown, a major aerospace/DOD contractor with 2000 engineers, and out of that group, he was selected as "Engineer of the year" a few years ago. No one pulled the wool over his eyes, he came, saw what we were doing, understood it wasn't certified nor TV tested, and chose to fly it anyway. It broke and he kept working with it, and today he is still a Corvair guy and he will eventually build another one with the Weseman crank that he bought, and I will assure you he will do this without spending 25K on a TV analysis before he flies it. Read his website, or better yet, meet him in person. He is nothing like some of the engineers on this group who probably think that TV is a requirement before they would fly a plane. He likes considering things, but while others waited and wrote thousands of posts, he went out and flew 1130 hours. Yes, he broke things, but it was his life and his choice.


    Ross has obviously achieved a lot in aviation, and I respect that. On Ross's website it states on the front page:
    "This product does not conform to any recognized set of standards or certifications for aviation applications."
    and
    "Use of this product on amateur built/ experimental aircraft is at the discretion of the buyer who accepts full responsibility for any consequences resulting from its use. Since Racetech Inc. cannot control the installation, programming, application environment or use of its products, we accept no responsibility for damage, loss or personal injury resulting from the use of SDS products. By using SDS products, the user understands and accepts this."
    .
    I see nothing wrong with that, and it is essentially identical to the message we have always sent to Corvair builders. If it is OK for him not to meet certified standards with his products, then it is OK for me to promote Corvairs that don't meet FAR 33, just as long as I don't tell people they do, which I never have. Note that Ross specifically address that he has no control over builders. This was exactly my position with Mark as a builder. And it was exactly how Mark wanted it. He would listen to others, but in the end he was going to use his own judgment to build his own plane, and he would be responsible for it. He wouldn't have it any other way.
    .
    For as much as some guys here think of this forum as the cutting edge and a great place for ideas, consider that Mark Langford probably doesn't agree with that. He showed up here for exactly two posts after he didn't like how people spoke about him and critiqued his work without having ever met him nor having ever built their own plane and engine. His webste has a section From: John Affleck That doesn't paint a "knowledgeable and friendly" image of HBA. Mark runs the Corvaircraft group and the KRnet, and if he wanted to he could be here also. Read his story, it is largely about one very annoying guy, but that guy and his comments fit in with the perspective that prevails here, which is one doesn't need to have ever seen an engine in peron, or even know the specific details about it to pass judgment on it.
    .
    -----------------------------------------------
    .
    On the specific topic of flight hours: The highest time Corvair in the world is Tom Browns Pietenpol. It has 1600 hours on it, it has no 5th bearing, it does not have a nitrided crank. It has not been apart since it was pit together in 1980. Full disclosure: My wife has flown Toms plane, is friends with him and can be seen hugging him in this photo : Thought for the Day: The color of your Day. | flycorvair
    .
    There are no 2000 hour engines. Ross's own plane is 400 hours in 11 years. He knows that a tiny fraction of homebuilts that are not used in some type of commercial venture like gyros ever get to 2000 hrs. We overhauled the engine in Bernard Pietenpol's "Last original". It flew 880 hrs 1977-2011. It had no 5th bearing, no nitriding, no crank issues, it was never apart. My Wife has flown it, it cruises at 3,000 rpm and generates perhaps 85-90 hp
    .
    I posted a link to Joe Horton's 3100 KR with nearly 1000 hours 400 of which were without a 5th bearing, all done on the same crank. There are many examples like this. I am sure that people will reject this as meaningless anecdotail information, so take it for what it means to you.
    .
    Ross obviously thinks that Subarus are great, and they meet his standards, and I am happy for him. I am sure there were issues they had also, and not everyone flew perfectly, and gave every user better experience than a factory new Lycoming, otherwise Jann Eggenfelner would still be building them. Likewise, I don't see the VW's he mentions as immune from issues either. There are no perfect engines nor perfect people, there are just people who will wait for the perfect engine, criticize what imperfect people work to build and fly in reality, and those who choose to do something real, recognizing the limitations of time money and lifespan.
    .
    The idea that I have been doing this for 25 years, worked very hard at teaching it to others, have worked to make a viable affordable option for builders, and I do this teaching in public at free colleges that anyone can attend means nothing to some people. Other people are thankful for it, not just because they didn't have the money for a Rotax or a Jab, but because I was the person willing to teach them things they wanted to learn, in an era where 'hombuilding' has largely become 'homebuying.' If all some guy wants out of aviation is to sit on the net and use a fake name to tell me my efforts are not valid, while the years go by and he has done nothing himself, never shared anything of his own efforts that when flying, never built his own alternative engine, great, I hope he is happy with his path. My journey has not been perfect, but it has been more rewarding to me than critiquing the work of others.-ww.
     
  9. Jan 27, 2015 #169

    William Wynne

    William Wynne

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    I find it odd that in the last few days, this thread has picked up ten times as many reads as the one directly below it: https://www.homebuiltairplanes.com/forums/corvair/20999-planes-flying-corvair-power-2015-a.html where I posted 15 links to stories about flying Corvair powered planes on our website. Even if the people following this thread are not specifically Corvair builders, I would think that more of them would at least give a cursory look at what is out there and flying. It seems like any comment, positive or negative, could be refined or improved by reviewing what is flying. -ww.
     
  10. Jan 27, 2015 #170

    ekimneirbo

    ekimneirbo

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    The Good, The Bad and the Ugly............Thats what I'd have to say about this thread.While I certainly understand WWs intensity, and admire his accumulation of Corvair and Flying
    knowledge, I can also understand that others do have knowledge ,opinions, and different experiences that they can bring to the discussion. Heck, if everyone had the same opinions
    we wouldn't even have this forum...there would be nothing to discuss. While a few folks have cried "foul" at the way WW expresses himself and his opinions, I really don't feel he has
    broken any rules.......and I for one have learned a heck of a lot about Corvairs that I could not be privy to if it wasn't for WWs comments. I feel that he has done a good job providing
    information.When all is said and done, I also feel it is up to me and anyone else viewing the site to decide if they want to accept any or all of WWs opinions. Is he correct on every
    deduction he makes? The simple law of averages says "probably not".......but at least I have more info than I had and can make my own decisions.
    We should all understand that while we enjoy this site as part of our chosen hobby, WW has chosen it as his field of endeavor, his way of life, and his way of making a living. I have
    gotten tired over the years of reading rediculous comments that soon become an accepted fact and drive builders away from alternative engines. So, personally I'm glad to see some
    of the really knowledgeable individuals who frequent this site dispel incorrect or misleading opinions with hard data based on experience. There are a handful of posters in the mold
    of WW and RV6guy who can really help all of us "wannabes" if we just put aside our egos and try to converse rather than just attempt to prove them wrong on something. Like I said,
    we can process it later and decide whether we agree, but for now lets take advantage of the opportunity thats presented to us.


    As an example, many people used to say that Lycomings had much larger thrust bearings than Chevy's or that they were so much more massive than a Chevy, but apparently these
    well intentioned individuals had never made an actual comparison and propagated the misinformation. When compared side by side the information proved to be incorrect......but
    how many people rejected the use of a Chevy because of misinformation? So I like it when someone says something they attempted to verify rather than just passed along because
    they heard it somewhere else. IMGP0329.jpg
     
    Last edited: Jan 27, 2015
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  11. Jan 27, 2015 #171

    BoKu

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    Actually, I was pretty impressed by the Corvair-powered KR I saw at O22. But, again, that is pretty much irrelevant to the topic of this thread.

    Again, Mr Wynne, I would respectfully suggest that you spend more of your energy addressing the message, and less addressing the messenger. To do otherwise is to waste your better years tilting at windmills.

    Thanks, Bob K.
     
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  12. Jan 27, 2015 #172

    ekimneirbo

    ekimneirbo

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    My point about the crankshafts was that the nitrided 140/180 cranks were readily available and known by Corvair engine builders decades ago to be far superior in fatigue resistance to the 95/110 cranks. I just don't understand why people would not always use them for an aircraft application. As I said in another thread, these cranks rarely need regrinding in the first place because they are so hard. As a race engine builder where I pay great attention to detail, I never reground cranks and was well aware of fillet radius importance. This seems to have been discovered by accident if you'll pardon the pun. It hardly seems to make sense coming from an authority on Corvair engines.

    You seem quick to dismiss Mark's experience as invalid with other flying Corvairs. Perhaps but also perhaps not. I'd be inclined to be open minded and try to learn something from it. Personally, I think Mark's decision not to fly another 8409 crank 3100 is pretty rational.

    Some more information which others might consider useful regarding Corvair engines, this coming from my good friend who is one of the most experienced and respected Corvair performance engine builders in the US- "Years ago it was uncommon for a crank to fail mag, now I am finding about 1/3 of the cranks show cracks. Most common is between the #5 and #6 rod journal, but I am also finding some between the #1 thrust and #2 rod.


    Last year about 1/2 of the cranks I had mag'ed were cracked. Maybe this was an unusual year, maybe it is going to be the norm for now on. I do not know, but will let you know in December. :)


    I have not noticed a significant difference in the failure rates between the factory nitrided cranks [140 and 180] and the non-nitrided cranks, but my sample size is too small to make any valid conclusions. We also have into play that very few standard cranks are still around so any 140/180 crank which is ground is no different than any other non-nitrided 1964-69 crank."

    Lesson- all cranks need to be mag'ed, grinding without re-nitriding is a bad idea. We all knew this in the Corvair world 30 years ago. I owned my first one back in 1978 and built many engines for street and race use- up to 350hp turbocharged. The knowledge was out there long ago.

    A good engine builder knows a lot about details and checks everything the machine shop touched prior to assembly to give the best possible reliability on the finished product. Of course we all learn new things as we go but I believe a modest, open minded and humble approach sits a lot better with with most people than saying we know it all and then have failures.


    [/QUOTE] Ross, that is a significant statement about Corvair crankshafts. I would like to hear further information about the use of these crankshafts (racing,offroad,daily driving,etc) prior to magnaflux. Had the cranks
    been previously ground, or did they come from specific year vehicles.....or specific horsepower vehicle? What I'm getting at (and WW is welcome to address this) is whether there may have been minor production or
    engineering changes thru the production years? Were all crankshafts manufactured at the same vendor and were they all ground by the same vendor, or were there multiple sources for GM. I know that the LS Chevy
    engines manufactured today often come from more than one vendor....same with some of the heads. What I'm getting at here is whether some vendor may have made a production run during one year and discovered
    that the radii were being ground incorrectly and fixed the problem in subsequent years. Could the supplier of the crankshafts prior to machining been from more than one vendor? I realize that this info may not be
    available, but who better to ask than you guys? If anyone else has personal knowledge of actual manufacturing of these engines, put it out there for the rest of us.
     
  13. Jan 27, 2015 #173

    proppastie

    proppastie

    proppastie

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    looking at your 5th bearing, What is that diameter of the shaft it is pressed onto, looks like about 1" also I am missing lots of parts here that get to the prop


    [​IMG]
     
  14. Jan 27, 2015 #174

    WonderousMountain

    WonderousMountain

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    I've studied under neem karoli baba, Amma, and new yorks master ghost buster Tim Tim Salabim.
    Am telekinetic, with he​​aling capacities.

    It is good that engineers traditionally don't apply magic to flying machines, they would crash more often due to ethereal incompetency.

    Glad the wesermans are doing a good job. Glad M Langford's uninjured.

    Lupi
     
  15. Jan 27, 2015 #175

    Autodidact

    Autodidact

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    Proppastie, that's a Dan Weseman 5th bearing (William Wynne's is different in that it has integral thrust faces). I believe that it is not pressed on, but fits onto the crank flange and has at least three screw adjustable wedges between the inner walls of the bearing journal and the crank flange so that it can be adjusted for concentricity, and that is how it can be installed on an otherwise assembled engine. The shaft sticking out is a "safety shaft" and threads into the Corvair crank's pilot bearing hole which has to be threaded. I think that the safety shaft may be something that Bernie Pietenpol had done on the original Corvair conversion? I can't adequately describe how the Weseman bearing works without a bunch of detailed pictures, so if my description is inadequate, sorry about that. Weseman's bearing is pretty ingenious, IMO.

    I also think that the Langford incident has been overblown; I can do a Google search on Corvair crankshaft failures and almost everything is a reference to Mark Langford. That is one incident (three, but still...) and is not helpful statistically I would think. If HBA is "guilty" in this overblowing, then it is probably because HBA is a popular forum and anyone can come here and talk about any aviation related subject they are interested in. It's a community and there are all kinds of people in a community. As far as getting a forum to behave in a certain way, you'd have better luck as a cat herder. That's why the rules are as simple as practically possible, I would think.
     
    Last edited: Jan 27, 2015
    fly2kads and BoKu like this.
  16. Jan 28, 2015 #176

    ekimneirbo

    ekimneirbo

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    I just knew legalizing weed in Colorado wasn't a good thing. :)
     
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  17. Jan 28, 2015 #177

    proppastie

    proppastie

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    its really easy to paste in a JPG guys, (not too big) Maybe someone will mount more pictures or links
     
  18. Jan 28, 2015 #178

    gschuld

    gschuld

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    FLY5THBEARING.COM

    Look in the corvair section, then 5th bearing. This is Dan Weseman' site. He supplies the most popular of the 5th bearing designs. He is also the designer of the Panther aircraft, and quite a good aerobatic pilot with both the Sonex/3100 corvair combinatin and the Panther/3000 corvair combinaions.

    George

    P.S. Your efforts are appreciated WW.
     
  19. Jan 28, 2015 #179

    Autodidact

    Autodidact

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    Apparently, it heightens your senses of humor :lick:.
     
  20. Jan 28, 2015 #180

    proppastie

    proppastie

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    THanks, it looks like a lot more strength. It really looks like a nice engine.

    As anyone that has built an aircraft knows the most important quality is persistence. These guys really have that quality. I really admire that. When I started to read this I laughed.

    "After flying a 3100cc William Wynne style Corvair for about 40 hrs the crankshaft failed. Around this time several others had also cracked crankshafts. They then turned to Nitriding to help increase the fatigue life of the crankshaft. That worked well but in early 2008 our friend Chris Smith (Son of Cleanex) and Mark Langford (KR-2S) both broke nitrided crankshafts! That was a wakeup call!"

    I am so sorry I have denigrated their efforts. I still like the front main on an aircraft engine better but the amount of work these guy do is admirable.



     

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