Lancair Legacy flaps torque tube

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Magisterol

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Anybody knows or have an idea of the Lancair 320 Legacy torque tube dimensions and material. I am assuming it is 4130 steel, but what diameter and wall thickness?
 
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Marc Zeitlin

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Anybody knows or have an idea of the Lancair 320 torque tube dimensions And material. I am assuming it is 4130 steel, but what diameter and wall thickness?
I'm not sure what "torque tubes" you're referring to - the flap system drawing on page 23 of Chapter 10 of the Lancair 320 plans shows two pushrods (FL9 and FL10) but no torque tubes:


Assuming that you're referring to the pushrods, that same drawing indicates the dimensions as 3/4" diameter x 0.035" wall. Doesn't say the material though - for that, you have to go to page 30, Step 3, where it indicates that they're "Aluminum". No specification - I'd assume 2024T3, because it's easily available.
 

Magisterol

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I'm not sure what "torque tubes" you're referring to - the flap system drawing on page 23 of Chapter 10 of the Lancair 320 plans shows two pushrods (FL9 and FL10) but no torque tubes:


Assuming that you're referring to the pushrods, that same drawing indicates the dimensions as 3/4" diameter x 0.035" wall. Doesn't say the material though - for that, you have to go to page 30, Step 3, where it indicates that they're "Aluminum". No specification - I'd assume 2024T3, because it's easily available.
Sorry, I should have put a drawing up. I don’t know if it is the old or new models.
 

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wsimpso1

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Sorry, I should have put a drawing up. I don’t know if it is the old or new models.
The page put up is for the Lancair Legacy, which is a Completely Different Airplane from the Lancair 320. When you want help about one bird, and you call it something else, the folks trying to help get sent on a wild goose chase, find out they had their time wasted, and then can become reluctant to help you or other folks later. Not the behaviour we should be encouraging...

I do not know what it will take to have a file we can do a useful enlargement on, but when I zoom in I find the page is so grainy, detail is lost and and text is obscured. Post a decent image and we might be able to help more. Right now, you are holding out for someone with experience in Lancair Legacy's that does not need the picture. But then the folks that might have Legacy experience, have already looked at this thread once and moved on....

I shall change the thread title and edit the OP...

Billski
 
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Marc Zeitlin

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Sorry, I should have put a drawing up. I don’t know if it is the old or new models.
So, yeah on what @wsimpso1 wrote - kind of a waste of my time when you talk about a Lancair 320, but mean a Legacy. In any case, all the Legacy build manuals are available here:


which include high quality PDF images, rather than crappy resolution PNG's.

Chapter 21 shows the flap torque tube as a weldment, implying that it's a 4130 steel tube with the welded belcranks on it. It does NOT say what the diameter or wall thickness is, but I'd bet that a call to the factory would get you that information:


Which is where I would have started (well, first I'd have started by making sure I knew which airplane I was actually building).
 

Magisterol

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Well, all my questions are addressed to people that know, like the owner of those airplanes. If they own the airplane, they would have set me right that “my airplane doesn’t have this system “. People that want to butt in and be helpfull, I don mind. As I said at the beginning “I am not sure”, that is why I posted. Had I known, I would have refrain from doing it. I didn’t ask you to do the search for me. I guess there are some ”specialists” here that “knows all “ and felt the need to express themselves.
 

BJC

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Well, all my questions are addressed to people that know, like the owner of those airplanes.
PM me on Wednesday, and I will give you the dimensions of the flap actuator torque tube used on the Glasair. It is proven in very similar service.

BJC
 

BJC

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Anybody knows or have an idea of the Lancair 320 Legacy torque tube dimensions and material. I am assuming it is 4130 steel, but what diameter and wall thickness?
For reference, the Glasair II, with slotted flaps (that require electric actuation because of high forces involved) uses a 4130 torque tube under the seats that is 1 1/8" X 0.058". I believe that the Glasair III uses the same tube.


BJC
 

Magisterol

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For reference, the Glasair II, with slotted flaps (that require electric actuation because of high forces involved) uses a 4130 torque tube under the seats that is 1 1/8" X 0.058". I believe that the Glasair III uses the same tube.


BJC
Thank you very much. it hit the spot. Thx.
 
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