Wow a lot of high tech talk happening here on this repair. This is a home built aircraft where none of all those rules and procedures need to take place. If you want to check your welders skills who is going to do a repair simply have 2 pieces of tubing cut and scarfed to fit together in a Tee or Y- joint configuration. Pieces only need to be about 4 inches long. Have your welder weld the test tubing together and let them cool. after it cools clamp one part of the tubing into a vice and slide a sleeve over the other piece and pry on it until the weld fails or the tubing fails by tearing apart. If the weld strength is good the tubing will rip apart just past the weld. If the weld itself is weak the weld bead will fail. Good video I like it.
Failure to stress relieve the welded area after finishing the weld will most likely result in the weld failing again. This is basic 101 procedure when fabricating aircraft frames and engine mounts with chrome molly tubing. Any repair to the tube not directly welded to a solid steel structure, or to a intersecting tube, must always be inner lined with a backer tube to add structure to the weakened area of the break. The failure to follow standard practices regarding air frame repairs puts the operator of the aircraft at risk. Any good, certified air frame mechanic knows this...............
Was also wondering if an aircraft specific certification was required for someone to repair or weld components to the aircraft? And then the aircraft mechanic that has to be certified to work on aircraft, but acknowledged that he couldn't weld that, is able to accept your weld by just looking at it? Something seems not right here! Would hate to think that anyone who says they can weld, can come along and weld parts to an aircraft and there's no issue with it, or no certification required, or no formal check of the weld to assure that it's good!
Usually this type of stress relief is done by multiple process. Most commonly you pre-heat area to be welded, make the weld, then install control heaters on welded area and bring it back down to normal temperatures over a long period of time. This process helps to eliminate the thermal shock (stress) of welding on cold metals or welds cooling down to fast. Never worked in aircraft industry though, so they may have some other process I am not familiar with.
yes i can read that too in a manual, i am talking about real world procedures, as mr swaim has extensive experience welding cr-mo frames maybe the op could add something. there are too many textbook welders around here and i want to learn something real
No text book, that was real world! Worked a lot in the nuclear industry, and that's how critical welds were handled. There were strict procedures that you had to follow about pre-heat, of course the welds, then how ceramic heaters had to be placed and how the temperate had to be brought down and over what period of time. Then welds were x-rayed. Again, not sure what real world in aircraft industry is though, and certainly don't have a text book on it either!
Appropriate FAA pubs should be referenced when performing repairs. See Section 5: www.faa.gov/documentLibrary/media/Advisory_Circular/AC_43.13-1B_w-chg1.pdf
Omg I’m building a Hummelbird! And upgrading to a more powerful engine on my dragonfly this is awesome!
Another excellent job and great information. I haven't been back to that airport in over 30 years, I miss it down there.
Can you tig weld the engine while on the airplane ?
Wow a lot of high tech talk happening here on this repair. This is a home built aircraft where none of all those rules and procedures need to take place. If you want to check your welders skills who is going to do a repair simply have 2 pieces of tubing cut and scarfed to fit together in a Tee or Y- joint configuration. Pieces only need to be about 4 inches long. Have your welder weld the test tubing together and let them cool. after it cools clamp one part of the tubing into a vice and slide a sleeve over the other piece and pry on it until the weld fails or the tubing fails by tearing apart. If the weld strength is good the tubing will rip apart just past the weld. If the weld itself is weak the weld bead will fail.
Good video I like it.
Failure to stress relieve the welded area after finishing the weld will most likely result in the weld failing again. This is basic 101 procedure when fabricating aircraft frames and engine mounts with chrome molly tubing. Any repair to the tube not directly welded to a solid steel structure, or to a intersecting tube, must always be inner lined with a backer tube to add structure to the weakened area of the break. The failure to follow standard practices regarding air frame repairs puts the operator of the aircraft at risk. Any good, certified air frame mechanic knows this...............
Was also wondering if an aircraft specific certification was required for someone to repair or weld components to the aircraft? And then the aircraft mechanic that has to be certified to work on aircraft, but acknowledged that he couldn't weld that, is able to accept your weld by just looking at it? Something seems not right here! Would hate to think that anyone who says they can weld, can come along and weld parts to an aircraft and there's no issue with it, or no certification required, or no formal check of the weld to assure that it's good!
pkav8tor would you explain the procedure for stress relieve the welded area?
Usually this type of stress relief is done by multiple process. Most commonly you pre-heat area to be welded, make the weld, then install control heaters on welded area and bring it back down to normal temperatures over a long period of time. This process helps to eliminate the thermal shock (stress) of welding on cold metals or welds cooling down to fast. Never worked in aircraft industry though, so they may have some other process I am not familiar with.
yes i can read that too in a manual, i am talking about real world procedures, as mr swaim has extensive experience welding cr-mo frames maybe the op could add something. there are too many textbook welders around here and i want to learn something real
No text book, that was real world! Worked a lot in the nuclear industry, and that's how critical welds were handled. There were strict procedures that you had to follow about pre-heat, of course the welds, then how ceramic heaters had to be placed and how the temperate had to be brought down and over what period of time. Then welds were x-rayed.
Again, not sure what real world in aircraft industry is though, and certainly don't have a text book on it either!
Appropriate FAA pubs should be referenced when performing repairs. See Section 5:
www.faa.gov/documentLibrary/media/Advisory_Circular/AC_43.13-1B_w-chg1.pdf