The 'What did you do in your workshop tonight?' thread
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Jetpainter
640cc Uber Pimp
Last night I pulled the Hangar 9 Extra apart to see what's damaged. I discovered something kind of interesting. The aluminum spinner backplate is broken, and not from the trip into the beans. It's cracked at the outside edge of the engine prop hub and was pushed back far enough to rub a big gouge in the cowl. I had killed the engine right after the spinner cone came off so the crack was there before it went in the beans.
I did check and found out I already have the wheel pant I need. Last time I broke the right one and bought a set, so the original left one is still good and sitting on my shelf. The lower cowl is cracked and needs some work, and the top half is cracked in three spots. One gear cuff is damaged, the landing gear is bent, and so is one axle.
It's not too bad, I only need to paint one color, the black metallic, and only need to buy a prop, spinner, and a set of axles. I'm thinking about a No Limitz fiberglass spinner so I can paint it to match the black metallic on the cowl.
I did check and found out I already have the wheel pant I need. Last time I broke the right one and bought a set, so the original left one is still good and sitting on my shelf. The lower cowl is cracked and needs some work, and the top half is cracked in three spots. One gear cuff is damaged, the landing gear is bent, and so is one axle.
It's not too bad, I only need to paint one color, the black metallic, and only need to buy a prop, spinner, and a set of axles. I'm thinking about a No Limitz fiberglass spinner so I can paint it to match the black metallic on the cowl.
49dimes
Damn I'm hungry
@Jetpainter Keep in mind this is coming from a brain dead old fart who ate too many cheeseburgers.....
I did notice in one of your earlier pics that part of the spinner cone retaining bolt was still in the engine prop shaft adaptor.
Do you think maybe it could have been "over tightened" causing a chain of events to failure ??? ie....Engines piston knock force transmitted energy to a weak spot in the spinner back plate which was under excessive pressure being forced back against engine drive hub due to overtightened retainer bolt. When the crack developed from knock force energy and pressure against engine drive hub back plate no longer centered spinner cone allowing centrifugal force to break off the spinner cone retainer bolt and allowing spinner cone to separate.
I did notice in one of your earlier pics that part of the spinner cone retaining bolt was still in the engine prop shaft adaptor.
Do you think maybe it could have been "over tightened" causing a chain of events to failure ??? ie....Engines piston knock force transmitted energy to a weak spot in the spinner back plate which was under excessive pressure being forced back against engine drive hub due to overtightened retainer bolt. When the crack developed from knock force energy and pressure against engine drive hub back plate no longer centered spinner cone allowing centrifugal force to break off the spinner cone retainer bolt and allowing spinner cone to separate.
Jetpainter
640cc Uber Pimp
That is certainly possible, though I'm not the kind of guy that tightens things till they squeak.@Jetpainter Keep in mind this is coming from a brain dead old fart who ate too many cheeseburgers.....
I did notice in one of your earlier pics that part of the spinner cone retaining bolt was still in the engine prop shaft adaptor.
Do you think maybe it could have been "over tightened" causing a chain of events to failure ??? ie....Engines piston knock force transmitted energy to a weak spot in the spinner back plate which was under excessive pressure being forced back against engine drive hub due to overtightened retainer bolt. When the crack developed from knock force energy and pressure against engine drive hub back plate no longer centered spinner cone allowing centrifugal force to break off the spinner cone retainer bolt and allowing spinner cone to separate.
Since the center bolt in that spinner was aluminum I was always extra careful about that. Another likely scenario is that I cracked the backplate by handling it by the spinner. When I need to move it sideways on the carpet in my family room I always tried to grab a prop blade and pick it straight up, but every once in awhile I would catch myself grabbing the spinner to pick up the front. On my 50-60cc planes that's not an issue since they don't weigh that much, but this pig weighs 30+ pounds assembled so it's a totally different story.I'm blaming myself one way or the other.
49dimes
Damn I'm hungry
Know exactly what you mean. But for me it's an EDF. Got a room full of mostly 3D junk but all I can really think about is getting the EDF's "wheels up"
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Jetpainter
640cc Uber Pimp
EDF's are fun that's for sure. I haven't flown my Mig 21 since January and need to change that very soon!Know exactly what you mean. But for me it's an EDF. Got a room full of mostly 3D junk but all I can really think about is getting the EDF's "wheels up"