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Re: Material: alu-tube rigidity
By:Bill Hamm
Date: 11/15/2012, 2:03 am
In Response To: Material: alu-tube rigidity (CarstenT)

: Hi All
: After visiting the yostwerks pages on building a folding-kayak I
: decided to build my own. As it is, I'm usually not following the
: prescription on anything, and so too as to a transportable
: kayak. My experience in the 'wild' stresses weight as a dominant
: and primary factor .. anyway, short story: I bought 20 1m*10mm
: carbon-fiber tubes to act as gunwale and chines with a set of 5
: 1m 30mm alu-tubes to act as a keel. I've been fiddeling with
: some of the minor details, but today I got 4 of the 5m alu-keel
: up and hanging in strings attached to each end. This setup does
: not reflect how it will respond in water, but .. gee, it's SOFT.
: Awful soft. My instinct tells me that it's too soft to act as
: the central and only 'rigid' structure to 'hang' everything else
: up on.
: Has any of you any idea weather I'm out on a too soft limb here?
: The alu-tubes are 30mm ø-outside 26mm ø-inside. They are attached
: by inlined tubes 24mm ø-outside 22mm ø-inside - the 2mm
: discrepancy covered with tape, but the bending of the long
: assembled tube is not particularly focussed here, it appears to
: be the overall elasticity of the collective tube.

All aluminum tubing is not created equal, what grade and hardness is the material you bought? There is a giant difference in strength between one of the common soft aluminum tubes compared to one of the marine grade or aircraft grade materials of the proper hardness. The difference can be as much as 300% or more.

Bill H.

Messages In This Thread

Material: alu-tube rigidity
CarstenT -- 11/14/2012, 3:26 pm
Re: Material: alu-tube rigidity
Marc Upchurch -- 11/14/2012, 6:55 pm
Re: Material: alu-tube rigidity
ancient kayaker -- 11/15/2012, 12:06 am
Re: Material: alu-tube rigidity
Bill Hamm -- 11/15/2012, 2:03 am
Re: Material: alu-tube rigidity
Brian Nystrom -- 11/15/2012, 7:18 am
Re: Material: alu-tube rigidity
Bill Hamm -- 11/16/2012, 10:22 am
Re: Material: alu-tube rigidity
Brian Nystrom -- 11/16/2012, 12:31 pm
Re: Material: alu-tube rigidity
CarstenT -- 11/16/2012, 5:32 pm
Re: Material: alu-tube rigidity
Marc Upchurch -- 11/16/2012, 9:22 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/17/2012, 1:39 pm
Re: Material: alu-tube rigidity
Marc Upchurch -- 11/17/2012, 3:53 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/18/2012, 12:35 am
Re: Material: alu-tube rigidity
Marc Upchurch -- 11/18/2012, 9:40 am
Re: Material: alu-tube rigidity
Bill Hamm -- 11/19/2012, 1:16 am
Re: Material: alu-tube rigidity
Mike Savage -- 11/17/2012, 3:54 pm
Re: Material: alu-tube rigidity
Marc Upchurch -- 11/17/2012, 7:07 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/18/2012, 12:38 am
Re: Material: alu-tube rigidity
Mike Savage -- 11/18/2012, 12:42 pm
Re: Material: alu-tube rigidity
Yostwerks -- 11/15/2012, 11:06 am
Re: Material: alu-tube rigidity
CarstenT -- 11/15/2012, 12:22 pm
Re: Material: alu-tube rigidity
Yostwerks -- 11/15/2012, 1:42 pm
Re: Material: alu-tube rigidity *PIC*
Yostwerks -- 11/15/2012, 2:02 pm
Re: Material: alu-tube rigidity
CarstenT -- 11/15/2012, 3:04 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/16/2012, 10:26 am
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/15/2012, 11:11 am
Re: Material: alu-tube rigidity
CarstenT -- 11/15/2012, 12:51 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/16/2012, 10:32 am
Re: Material: alu-tube rigidity
CarstenT -- 11/16/2012, 5:53 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/17/2012, 1:42 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/16/2012, 10:29 am
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/16/2012, 11:21 am
Re: Material: alu-tube rigidity
Bill Hamm -- 11/17/2012, 1:44 pm
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/17/2012, 3:53 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/18/2012, 1:45 am
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/18/2012, 1:56 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/19/2012, 1:19 am
Re: Material: alu-tube rigidity
CarstenT -- 11/16/2012, 6:53 pm
Re: Material: alu-tube rigidity
Marc Upchurch -- 11/16/2012, 9:29 pm
Re: Material: alu-tube rigidity
CarstenT -- 11/17/2012, 5:30 am
Re: Material: alu-tube rigidity
Yostwerks -- 11/17/2012, 10:40 am
Re: Material: alu-tube rigidity
Bill Hamm -- 11/17/2012, 1:47 pm
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/17/2012, 4:07 pm
Re: Material: alu-tube rigidity
CarstenT -- 11/17/2012, 4:34 pm
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/17/2012, 5:40 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/18/2012, 1:50 am
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/18/2012, 2:10 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/19/2012, 1:22 am
Re: Material: alu-tube rigidity
Bill Hamm -- 11/18/2012, 1:51 am
Re: Material: alu-tube rigidity
Jeff Buyer -- 11/18/2012, 2:07 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/19/2012, 1:25 am
Re: Material: alu-tube rigidity *PIC*
Yostwerks -- 11/19/2012, 10:14 am
Re: Material: alu-tube rigidity
CarstenT -- 11/18/2012, 4:31 am
Electrolysis
CarstenT -- 6/2/2013, 6:39 am
Re: Electrolysis
Jeff Buyer -- 6/2/2013, 7:39 am
Re: Electrolysis
CarstenT -- 6/2/2013, 9:46 am
Re: Electrolysis
Tom Cooper -- 6/2/2013, 10:35 am
Re: Electrolysis
CarstenT -- 6/2/2013, 12:57 pm
Clogged up hinges. Solution
CarstenT -- 6/26/2013, 4:43 am
Re: Material: alu-tube rigidity
JohnAbercrombie -- 11/18/2012, 3:03 pm
Re: Material: alu-tube rigidity
Bill Hamm -- 11/19/2012, 1:33 am
Re: Material: alu-tube rigidity
Yostwerks -- 11/19/2012, 9:48 am
Re: Material: alu-tube rigidity
CarstenT -- 10/17/2014, 5:31 am
Re: Material: alu-tube rigidity
Bill Hamm -- 10/17/2014, 9:56 am
Re: Material: alu-tube rigidity
CarstenT -- 10/18/2014, 6:00 am