I am hoping that someone who has fabricated an Airbike fuselage from scratch, or has practical experience of welding other airframes, can help me with some welding advice please?
I need to make a replacement fuselage and other welded components for my Airbike from scratch as a number of the welded joints on my original fuselage have failed. I am not an experienced welder but it is obvious to me (and others who have seen the welding) that all of the welded joints that have broken lack penetration and fusion, with signs of porosity. The broken joints look brittle. Because of this I cannot trust any of the welded joints on the aircraft, and have been advised to consider all of them unsafe - vertical and horizontal stabilisers, control column torque tube, rudder pedals, etc. I have also been advised that it is not possible to now make this airframe good by way of repair as the integrity of the 4130 tube has been permanently compromised by the original poor welding.
I have been given two quotes by reputable fabricators to make just a new fuselage from scratch, their quotes were £4,000 and £5,000. I can understand the high cost because of the amount of labour involved - building jigs, notching lots of joints, slow TIG welding, etc. However, I simply cannot afford (or justify to my family) this amount of money, especially as I have already spent around £12,000 on the Airbike through the course of the three-year build.
I am incredibly frustrated as the Airbike is now grounded with just 45 minutes of flying time on it, having put in around 800 hours to build it. I have the only Airbike currently in the UK, so there is no possibility of buying a used airframe. The only (affordable) way forward now that I can see is to do all of the fabrication of new components myself. This would mean buying 4130 tube, building a jig, and welding. Many years ago I did some gas welding but have no experience of MIG or TIG.
So my questions: - would it be acceptable to gas weld, or does it have to be TIG welded? I imagine that I could re-learn gas welding with relative ease, but that TIG would be considerably harder to master and cost a lot more? Either way I would need to buy/rent/borrow the equipment. - is there anything else I need to consider. For example, the order of construction? Stress relieving?
Tough situation you are in. Absolutely acceptable to gas weld if that's what your comfortable with. You could probably learn TIG, I find it easier than gas welding as you have fantastic control over the heat input. But with the cost of buying equipment, and learning, maybe its worth paying an expurt? (And I've met met many an expurt I would never let anywhere near my stuff) Another option? Build a Himax or Minimax? With minor modifications to your existing wings your good to go?
From everything I have read gas welding is perfectly acceptable and maybe even preferred for cromoly tubing construction in aircraft. I believe I have seen it recommended to use a slightly carbuerizing flame and avoiding an oxidizing flame. EAA has some books/videos on aircraft welding that might be a worthwhile investment for education in acceptable methods.
I might also suggest you look at the Legal Eagle information. That design seems to have more builders and current activity than the Airbike. And they have much in common in their design and construction. You can find many websites and videos showing Legal Eagle fuselage construction and jigs to give you a head start.
Nigel i had a professional welder repair my a/b fuselage useing gas. he was going to tig weld it but his machine was down. he said either method will work. i am not a welder but do play around with a small mig welder for around the house repairs. unless i had the proper training i would never attempt to build a complete welded fuselage then put my life in it. not worth the risk. i would either have it built by a pro or find a different a/c.
Go for gas welding, take a little practice on scrap first. It produces a less "hard" weld and you can "normalize the joints after your done. If it was me I would try a repair on one of the joints (see a publication on repairing aircraft welded tube structures)and test it before discarding the whole lot. The fuselage of my Monerai (see my avatar) is entirely gas welded. The internal structure is very much like a space tube car frame. I did not weld up my Airbike as I purchased it used. Good luck
Gas welding chrome moly was an accepted procedure for welding a long time before TIG got popular. As far as your joint repairs, licensed mechanics have been installing sleeves on fractured joints as an acceptable form of repair since things have been getting broken. I would peruse your local library on techniques for such repairs as there has to be literature somewhere that describes these procedures.
Thank you all for all of your thoughts and comments, all of which I have found very helpful and have given me food for thought. I am a first time builder so have a lot to learn!
Last night I looked at YouTube videos of Legal Eagle construction, some very good pointers here and left me feeling much more confident about going down the gas welding route myself. I have also looked at a number of EAA videos, again very helpful. I also explored how airframe tube repairs are carried out - sleeves, rosettes etc - so this too opens up new possibilities.
Monte - I take your point about the risk of welding myself versus getting an expert to do the job. Unfortunately I have now learned the hard way that even the ‘experts’ can get it wrong. I had (perhaps naively?) assumed that the pre-welded fuselage supplied with my Airbike kit would have been welded by a competent and suitably qualified professional welder, and that the finished product would have gone through some sort of quality control process by the manufacturer before leaving the factory. Wrong and wrong! I regret now going ahead with the build when I did as my gut feeling at the time was that the welding was not good. A number of people have commented in various forums that ‘good welding looks good’ and I was not impressed with any of the welding I was seeing in my kit - should have trusted my gut feeling. At least if I do the welding myself I can do some destructive testing on practice pieces to see if they hold up, and get one or two experienced welders to take a look at finished welds and give their opinions.
So where to now?
I know it will be a major job to get my Airbike flying again, but having explored many options including scrapping the Airbike altogether, or buying a cheap used microlight, or stopping flying altogether (I am semi-retired and have to watch the pennies) I feel quite determined to get my Airbike in the air again. It has been my dream since childhood to build and fly my own aircraft, and I really don’t want to let go of this. I cannot even begin to tell you how disappointed I am about what has happened with the welding, but I try to remain positive and think of how I can get it back in the air. I had considered the Himax-fuselage type route, but as an ex-biker and ex-military parachutist I really like the openness of the Airbike and the good all-round visibility it offers. Perhaps it is the Adrenalin rush?!!!
The sticking point in my mind now is that none of the welded joints can be trusted, and this problem is not just confined to the fuselage. To give an idea of the scale of the problem, two of the welded components simply came off in my hand when I was building the kit - no force had been applied. Other weld failures occurred during the build process. I fitted a new Rotax 447, and when I ran the engine for the first time, to run it in, welds in the firewall area cracked. I had these professionally repaired by a CAA approved welder. Later the tail wheel fell off when the weld on the lower longerons failed. Again, repaired by a CAA approved welder. More recently several welds on the undercarriage failed causing the undercarriage to collapse. The engine was running at the time so I need a new propellor and to get the engine/gearbox shock tested. So yes, I can see how repairs could be carried out in some areas by, for example, use of sleeves. But what about more difficult areas such as the cluster welds on the fuselage, and the hinge pins on both the rudder and elevator? I do worry about the elevator horn, this is covered with Dacron at present so I can’t see but what is the welding like on it? Imagine if it failed!
I am beginning to feel more positive now about the possibility of repairing the old fuselage as opposed to building a new fuselage from scratch, and doing this work myself. If possible, then this could be a huge saving in both time and money, which in my current circumstances would be very welcome (one of the unforeseen casualties of not being able to build hours on my Airbike is that my licence will shortly lapse due to lack of hours/currency in my log book, and it will be a costly exercise for me to re-validate it under UK regulations, so any savings I can make will help).
If anyone can help with suggestions, particularly about repairing cluster welds, that would be appreciated. Once again, thank you all for your help with this, it is truly appreciated.
Is there any way to address the problem through the kit manufacturer? I feel your pain.I took a gas welding course through EAA last winter and it was very helpful for people like me that were trying it for the first time but I could see that much practice would be needed before attempting to weld clusters. The instructor was able to produce really nice cluster welds but even he was some what challenged.
I did make contact with the kit manufacturer in USA. I prefer not to name the manufacturer as I don’t want to harm his business, from what I have read he seems to be a decent person and I do believe he supplied the kit in good faith. However I have found it very difficult to communicate with him as he rarely answers the phone and clearly is not a fan of email. I did manage to catch him by phone one day (I had a week earlier sent a lengthy email with photographs which he told me he had not seen, I re-sent it to his company email address and his personal email address at the company). Having seen photographs of the broken welds he then replied by email, saying that he was sorry and offering as ‘company policy’ $2,850US, which I later found is the amount he is now selling a pre-welded fuselage for. This equates to about £2,200 at current exchange rates. As it would cost me more than double this amount to fix the Airbike, more like $7,000US - new fuselage and new prop and engine shock testing - I wrote back (politely) saying that I thought his offer was insufficient, my case being that all of these costs without exception were due to the failure of welds and not through any fault of my own, and asked him to reconsider his offer. This was back in September, since then I have repeatedly tried to contact him by phone and by email but cannot get a reply. I had hoped to reach some sort of amicable and reasonable agreement with him, but tomorrow it will be December and I am now thinking am I being naieve again in expecting to get a reply?
I had previously tried to post photos of my Airbike to this site when I finished building it, but was not successful. I only have an iPad, and this may be why? I will try and get my son to use his PC over the weekend to post some photos of the broken welds. By the way, three CAA-approved welders have seen the welding and have described it as ‘poor’, ‘very poor’ and ‘shockingly poor’. All three have kindly offered to put in writing their professional opinions about the quality of the welding, one was particularly angry that a fellow ‘professional’ welder working in aviation could produce work of this quality.
One of my concerns was that other Airbike builders supplied by the manufacturer around the same time as my own may be at risk due to sub-standard welding, in his reply he indicated that mine was down to a welder he employed at the time who ‘was not as certified as he led on to be’. I hope he let him go! My kit would have been manufactured around Autumn 2014.
And after all that you do not want to name the company for fear of doing him wrong? Would you like to prevent this from happening to anyone else? I only know of one Airbike kit manufacturer, so I guess I know who it is. Would he offer, and would you accept, a replacement fuselage with free shipping? That is if he has a new welder now.
Flydog - yes, my next move if I had been able to make contact with the manufacturer would have been to propose exactly what you have suggested, a replacement fuselage with free shipping. This would still leave me financially short of the true cost to get back in the air but would be a compromise I could live with. Provided of course that the welding was up to standard!
Akwrencher - thanks for your comment and the link to Homebuilt Airplanes, I will look in to this.
If this "manufacturer" does not stand behind his product and make good on his faulty procedures he should be exposed very publicly, so other people aren't subjected to his profiteering. There should be some legal recourse available, but alas, lawyers and courts are more costly than your repairs. Could try his local Better Business Bureau? Quality control is totally his responsibility.
Wow, scrap that frame before it kills someone! Chalk this up as a lesson learned, buy some 4130, learn to gas weld, and weld a fuselage up yourself. It’s a skill worth having. Make and destroy a bunch of test clusters before you start in on the real deal though. If I can do it anyone can!
If they hired a new welder and they are offering to send a frame or give the equivalent money to a new frame from them, that doesn't sound like a terrible deal... Much easier then welding another one.
If all else fails, provided its atleast built to dimensions, you can make up some jigs from it. Lay it on a sheet of cheap mdf and fasten some blocks as guides, if the "manufacturer" doesn't correct the obviously flawed fusalage you got I see no moral qualm with reproducing it in a safe form (and in multiple numbers). It angers me to see this, it's bad, and gives a black eye to the whole industry, that should have never shipped from production, and if it slipped past quality control they should be trying their best to get it back with "consideration" for the inconvenience caused.
Nigel, That workmanship, or lack there of, is criminal! One of my friends here in Tennessee has a "one off" Airbike fuselage. I won't go into the differences but it was made by the same person who made fuselages for the original TEAM company. I also don't want to talk about cost, but it might be more reasonable then you making a new fuselage from scratch. Even with shipping I believe you would come out way better.If you are interested send me an email gregandjanedoe@aol.com, and I'll give you more details. Greg
At the moment I remain open to all possible routes that could get my Airbike back in the air. I have done a lot of research recently into jigs, welding methods, steel suppliers, how to repair steel tube, etc. I am feeling more inclined now toward gas welding, if I were to do the job myself, but realise this would be quite an undertaking so if other possibilities exist I will explore these too before making a final decision.
Stilson - ‘consideration’ is a good way of putting it. I too think this is warranted in the circumstances.
Greg - thanks for your offer, Sounds interesting, I will pm you.
One of my friends here in Tennessee has a "one off" Airbike fuselage. I won't go into the differences but it was made by the same person who made fuselages for the original TEAM company.
I assume you mean Jim Doyle. I also had one if his fuselages and the welding was excellent.
It's not Jim Doyle who has the fuselage, but yes, he did build it. I'm pleased to report that I talked with the owner, and looked at his fuselage today. I also talked with Nigel Allen,and we are working on a solution. One question; does anyone have any experience shipping large, light weight items to England, or anywhere overseas. In my searching for Airbike fuselages I concluded who might be responsible for the bad fuselage, and Nigel confirmed my suspensions, but it's not my place to reveal it publicly. I did learn from Nigel that there might be a second bad fuselage in France! Nigel and I had a great conversation, and it was a first for me to phone England. We touched on the important items, but the "lynch pin" on the deal will be shipping. I hope my wife doesn't see our next phone bill!
Hi Greg; I know the person you are talking about very well. I think that fuselage is a 2 place also. The only problem, he likes to collect stuff and doesn't like to sell stuff, LOL. But if he might sell, the fuselage might be able to be converted to single place? just a thought. Bob
Bob, I'm sure your guess is correct, and yes he is a "collector". It might appear to be a two place, but it's a single "wide body" fuselage. Apparently Jim Doyle is a larger man, and built this fuselage for himself. We made a quick measurement yesterday, and it's approximately 24" wide. Not quite wide enough to be a two place side by side, and definitely not long enough to be a tandem. I think the owner is ready to part with some of his "stash" of prized possessions!
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