Author Topic: Aluminum Tubing  (Read 213 times)

danieldorgan

  • Subscriber
  • registered
  • *
  • Join Date: Apr 2015
  • Posts: 10
  • My Gallery
  • Engine: Revmaster?
  • Sonerai Model: Sonerai 2 Stretch
Aluminum Tubing
« on: Dec 27, 2017 »
I have owned a few mountain bikes and they exclusively use aluminum or carbon fiber. Steel tubing while heavy is the norm for rag and tube aircraft. I am wondering why no one uses aluminum tubing to construct the fuselage? Is it cost or durability? I've never cracked a bike frame in spite of some ham fisted handling. Bike tubes are of however of a shorter length. Could that be the issue? Disclaimer - I do not have the planning ability, knowledge, budget etc. to go the aluminum route. Just trying to absorb as much as possible.

kennyw

  • Subscriber
  • registered
  • *
  • Join Date: Aug 2017
  • Posts: 27
  • My Gallery
  • 2nd "Caretaker" N994SP
  • Engine: GP 1835
  • Sonerai Model: IIL
Re: Aluminum Tubing
« Reply #1 on: Dec 27, 2017 »
Not an engineer.  But, I'll post this link: https://sciencing.com/strength-tubing-vs-steel-tubing-7811536.html

Some ultralights do use aluminum tubing.  But, with slower speeds and lower weights, the energy potential is much lower.

Bil438

  • Subscriber
  • registered
  • *
  • Join Date: Oct 2007
  • Posts: 704
  • My Gallery
  • Engine: Jabiru 3300 120 hp
  • Sonerai Model: II LS
Re: Aluminum Tubing
« Reply #2 on: Dec 28, 2017 »
Well, while the best allow aluminum 7075-T6 is as hard as mild steel it Ultimate Tensile strength is less that 100,000 psi. If my memory is right then about 70,000 psi. 4130 Chromoly when brought to full strength is 385,000 psil. Thus 4130 can be more than 5 times as strong as 7075. True, 4130 after welding is nowhere near full strength...
Also 4130 lends itself very nicely to oxy-acetylene welding where like TIG only, the parent metal is melted into small pools and filler rod is added to the molten pool. Thus there are no cold welds in Oxy/act welding. In my experience aluminum alloys cannot be Oxy-act welded. 
Most homebuilders can work up their technique to be able to produce acceptable welds with oxy-acetylene, whereas it's a much bigger deal to produce an acceptable weld in TIG and the initial setup is much more expensive. You also usually need to have 220V available and most shops ,garages and hangars do not.
Finally the homebuilt aircraft suppliers are set up to sell tubing kits with all the material you need to weld up a fuselage. rarely so with aluminum tubing.
BillE

 

Recent Topics

Photo file size by Chucker
Jan 19, 2018

Chucker's Sonerai II (minus) by Pttim
Jan 19, 2018

Ribblet Airfoils by Bobcat Kid
Jan 18, 2018

Oil Cooler Adapter by Chucker
Jan 15, 2018

Aeromomentum Engines by Smokyray
Jan 15, 2018

Jabiru 3300 engine by Bil438
Jan 15, 2018

Rotax 582 by Chucker
Jan 14, 2018

FS: Aluminum Sheet by eschrom
Jan 14, 2018

A sad day! by N127PZ
Jan 13, 2018

What is longest length of single tube for 2 Stretch? by Soneraifred
Jan 13, 2018

Fuel line connections by Smokyray
Jan 03, 2018

Racegunz's Sonerai 1 by racegunz
Jan 03, 2018

Counterweights by racegunz
Dec 31, 2017

Elevator Trim Cable by myles-dean
Dec 31, 2017

Powered by EzPortal