Evacuated Frame Tubes: Stronger and Lighter

[B. Sanders]

The new evacuated frame tubing is the final frontier for the gram shaver. According to the
manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing has the added benefit of
permanent rust prevention (no air means no oxidation).

Has anybody tried one of the early-mid-year 2004 frames built with evacuated tubing (known to
framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")? I'm curious to know
more about the special handling characteristics of this new frame technology.

Barry

 

[Res09c5t]

Why not go one better and fill them with helium after evacuation and shave some more grams?

I'm not an engineer but the idea of the walls being in "tension" sounds fishy to me. Hopefully our
engineers will discuss that for us.

Lyle

"B. Sanders" <[email protected]> wrote in message news:104pa.563833$L1.164874@sccrnsc02...
> The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
> tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
> thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing
has
> the added benefit of permanent rust prevention (no air means no
oxidation).
>
> Has anybody tried one of the early-mid-year 2004 frames built with
evacuated
> tubing (known to framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")?
> I'm curious to know more about the special handling characteristics of this new frame technology.
>
> Barry

 

[John Forrest To]

"res09c5t" <[email protected]> wrote in message news:[email protected]...
> Why not go one better and fill them with helium after evacuation and shave some more grams?

How could helium be lighter than nothing?

JT

--
*******************************************
NB: reply-to address is munged

Visit http://www.jt10000.com
*******************************************

 

[Andy Coggan]

"B. Sanders" <[email protected]> wrote in message news:104pa.563833$L1.164874@sccrnsc02...
> The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
> tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
> thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing
has
> the added benefit of permanent rust prevention (no air means no
oxidation).
>
> Has anybody tried one of the early-mid-year 2004 frames built with
evacuated
> tubing (known to framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")?
> I'm curious to know more about the special handling characteristics of this new frame technology.

Man! I'd get a new ISP if it took three weeks for my posts to reach a newsgroup.

Andy Coggan

 

[Andy Coggan]

"John Forrest Tomlinson" <[email protected]> wrote in message
news:[email protected]...
> "res09c5t" <[email protected]> wrote in message news:[email protected]...
> > Why not go one better and fill them with helium after evacuation and shave some more grams?
>
> How could helium be lighter than nothing?

It isn't, but it's lighter (less dense) than the N2, O2, CO2, Ar, etc. normally filling the tubes.
(Now if only that He would stay put just as easily.)

Andy ("humid air is less dense - really") Coggan

 

[Ajames54™]

On Tue, 22 Apr 2003 05:00:45 GMT, "B. Sanders" <[email protected]> wrote:

>The new evacuated frame tubing is the final frontier for the gram shaver. According to the
>manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
>tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
>thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing has the added benefit of
>permanent rust prevention (no air means no oxidation).
>
>Has anybody tried one of the early-mid-year 2004 frames built with evacuated tubing (known to
>framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")? I'm curious to
>know more about the special handling characteristics of this new frame technology.
>
>Barry
>
Sounds stupid to me... though I suppose if the welding was done in a vacuum then you could seal the
top-tube, down-tube and the stays... but there would have to be no bottle bosses on the down tube..

Or is it that the tubes have internal walls to create a void that can then be evacuated? ...

hmmm ... I've heard of stupider things, but not often and usually a little closer to the first of
the month.

 

[Dave Lehnen]

Andy Coggan wrote: <snip>
>> How could helium be lighter than nothing?
>
>
> It isn't, but it's lighter (less dense) than the N2, O2, CO2, Ar, etc. normally filling the
> tubes. (Now if only that He would stay put just as easily.)
>
> Andy ("humid air is less dense - really") Coggan
>
>

To get the maximum benefits of vacuum, you need to pull several atmospheres of vacuum, really put
the ether in serious tension.

To maximize the lightness added by helium, use liquid helium so that more buoyancy can be crammed
into the frame.

Titanium frames should be replaced with granite frames, since granite has lower density
(look it up).

Dave Lehnen

 

[Archer]

In article <[email protected]>, [email protected] says...
> "John Forrest Tomlinson" <[email protected]> wrote in message
> news:[email protected]...
> > "res09c5t" <[email protected]> wrote in message
> > news:[email protected]...
> > > Why not go one better and fill them with helium after evacuation and shave some more grams?
> >
> > How could helium be lighter than nothing?
>
> It isn't, but it's lighter (less dense) than the N2, O2, CO2, Ar, etc. normally filling the tubes.
> (Now if only that He would stay put just as easily.)

He said the tubes are _evacuated_, which means the air has been pumped out, and they are now in a
vacuum. The main thing which jumped out at me is that he said the tubes were under tension, when
actually they would be in compression if the insides were evacuated.

--
David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
it's morning".

Remove the ns_ from the address before e-mailing.

 

[Andy Coggan]

"archer" <ns_archer1960@ns_hotmail.com> wrote in message news:[email protected]...
> In article <[email protected]>,
> [email protected] says...
> > "John Forrest Tomlinson" <[email protected]> wrote in
message
> > news:[email protected]...
> > > "res09c5t" <[email protected]> wrote in message
> > > news:[email protected]...
> > > > Why not go one better and fill them with helium after evacuation and shave some more grams?
> > > >
> > >
> > > How could helium be lighter than nothing?
> >
> > It isn't, but it's lighter (less dense) than the N2, O2, CO2, Ar, etc. normally filling the
> > tubes. (Now if only that He would stay put just as easily.)
>
> He said the tubes are _evacuated_, which means the air has been pumped out, and they are now in a
> vacuum. The main thing which jumped out at me is that he said the tubes were under tension, when
> actually they would be in compression if the insides were evacuated.

JFT said nothing about tubes being evacuated or being under tension - for some strange reason did
you think I was responding to the original poster??

Andy Coggan

 

[Archer]

In article <[email protected]>, [email protected] says...
> "archer" <ns_archer1960@ns_hotmail.com> wrote in message
> news:[email protected]...
> > In article <[email protected]>, [email protected]
> > says...
> > > "John Forrest Tomlinson" <[email protected]> wrote in
> message
> > > news:[email protected]...
> > > > "res09c5t" <[email protected]> wrote in message
> > > > news:[email protected]...
> > > > > Why not go one better and fill them with helium after evacuation and shave some more
> > > > > grams?
> > > >
> > > > How could helium be lighter than nothing?
> > >
> > > It isn't, but it's lighter (less dense) than the N2, O2, CO2, Ar, etc. normally filling the
> > > tubes. (Now if only that He would stay put just as easily.)
> >
> > He said the tubes are _evacuated_, which means the air has been pumped out, and they are now in
> > a vacuum. The main thing which jumped out at me is that he said the tubes were under tension,
> > when actually they would be in compression if the insides were evacuated.
>
> JFT said nothing about tubes being evacuated or being under tension - for some strange reason did
> you think I was responding to the original poster??

It was a combined response to JFT's, yours and the OP. My point was that helium would be lighter
than an air-filled frame, but not as light as a vacuum-filled one, and that the OP's mention of an
evacuated frame being under _tension_ was incorrect; it would be under compression.

--
David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
it's morning".

Remove the ns_ from the address before e-mailing.

 

[Captain Dondo]

On Tue, 22 Apr 2003 01:00:45 -0400, B. Sanders wrote:

> The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
> tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
> thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing has the added benefit of
> permanent rust prevention (no air means no oxidation).
>
> Has anybody tried one of the early-mid-year 2004 frames built with evacuated tubing (known to
> framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")? I'm curious to
> know more about the special handling characteristics of this new frame technology.
>
> Barry

Have you ever seen the high school experiment where you fill a can (any can) with a teaspoon of
water, then heat, cap tightly, and douse with cold water? Watch it crumble. Same thing happens to
water towers if the relief valve fails.

The forces on the tubes would be so huge that the walls would have to be so thick - the bulk of the
forces would be applied to the walls of the tube and not the endpoints. Seems that we need to look
at post-tensioned bicycle frames to achieve the right effect - run a cable down the center of each
tube, tension to several hundred (or thousand) pounds....

Hmmmm.. A bicycle frame that can double as a 3 string guitar.....

-Dondo

 

[Peter Cole]

"Captain Dondo" <[email protected]> wrote in message
news[email protected]...
> On Tue, 22 Apr 2003 01:00:45 -0400, B. Sanders wrote:
>
> > The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> > manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls
> > in tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective
> > for thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing has the added
> > benefit of permanent rust prevention (no air means no oxidation).
> >
> > Has anybody tried one of the early-mid-year 2004 frames built with evacuated tubing (known to
> > framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")? I'm curious to
> > know more about the special handling characteristics of this new frame technology.
> >
> > Barry
>
> Have you ever seen the high school experiment where you fill a can (any can) with a teaspoon of
> water, then heat, cap tightly, and douse with cold water? Watch it crumble. Same thing happens to
> water towers if the relief valve fails.
>
> The forces on the tubes would be so huge that the walls would have to be so thick - the bulk of
> the forces would be applied to the walls of the tube and not the endpoints. Seems that we need to
> look at post-tensioned bicycle frames to achieve the right effect - run a cable down the center of
> each tube, tension to several hundred (or thousand) pounds....

I think one of the land speed record vehicles used pressurized tubular framework with sensors. The
idea was that if the frame cracked anywhere, the pressure would drop and sound an alarm.

 

[Mike Causer]

On Tue, 22 Apr 2003 20:29:56 +0000, Peter Cole wrote:

> I think one of the land speed record vehicles used pressurized tubular framework with sensors. The
> idea was that if the frame cracked anywhere, the pressure would drop and sound an alarm.

Porsche 917, two-seat long-distance racing car. Although IIRC there was no alarm, just a
pressure gauge.

Mike

 

[James Connell]

archer wrote:

> In article <[email protected]>,
> [email protected] says...
>
>>"archer" <ns_archer1960@ns_hotmail.com> wrote in message
>>news:[email protected]...
>>
>>>In article <[email protected]>, [email protected]
>>>says...
>>>
>>>>"John Forrest Tomlinson" <[email protected]> wrote in
>>
>>message
>>
>>>>news:[email protected]...
>>>>
>>>>>"res09c5t" <[email protected]> wrote in message
>>>>>news:[email protected]...
>>>>>
>>>>>>Why not go one better and fill them with helium after evacuation and shave some more grams?
>>>>>
>>>>>How could helium be lighter than nothing?
>>>>
>>>>It isn't, but it's lighter (less dense) than the N2, O2, CO2, Ar, etc. normally filling the
>>>>tubes. (Now if only that He would stay put just as easily.)
>>>
>>>He said the tubes are _evacuated_, which means the air has been pumped out, and they are now in a
>>>vacuum. The main thing which jumped out at me is that he said the tubes were under tension, when
>>>actually they would be in compression if the insides were evacuated.
>>
>>JFT said nothing about tubes being evacuated or being under tension - for some strange reason did
>>you think I was responding to the original poster??
>
>
> It was a combined response to JFT's, yours and the OP. My point was that helium would be lighter
> than an air-filled frame, but not as light as a vacuum-filled one, and that the OP's mention of an
> evacuated frame being under _tension_ was incorrect; it would be under compression.
>
>
yes and have you ever evacuated an Al can and then tapped the surface? it collapses!

 

[Mike Causer]

On Tue, 22 Apr 2003 12:15:58 +0000, Dave Lehnen wrote:

> To get the maximum benefits of vacuum, you need to pull several atmospheres of vacuum, really put
> the ether in serious tension.

Don't you mean torsion?

Mike "Looking for a phlogiston-filled frame"

 

[S. Anderson]

"B. Sanders" <[email protected]> wrote in message news:104pa.563833$L1.164874@sccrnsc02...
> The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
> tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
> thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing
has
> the added benefit of permanent rust prevention (no air means no
oxidation).
>
> Has anybody tried one of the early-mid-year 2004 frames built with
evacuated
> tubing (known to framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")?
> I'm curious to know more about the special handling characteristics of this new frame technology.
>
> Barry
>
>

Shameless troll!!! Back under the bridge!! Back!!

Cheers!

Scott..

 

[David Storm]

Why not just construct a frame made of Cavorite?

"B. Sanders" <[email protected]> wrote in message news:104pa.563833$L1.164874@sccrnsc02...
> The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
> tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
> thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing
has
> the added benefit of permanent rust prevention (no air means no
oxidation).
>
> Has anybody tried one of the early-mid-year 2004 frames built with
evacuated
> tubing (known to framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")?
> I'm curious to know more about the special handling characteristics of this new frame technology.
>
> Barry

 

[H. Guy]

> > The new evacuated frame tubing is the final frontier for the gram shaver.
>
> Shameless troll!!! Back under the bridge!! Back!!

okay, silly idea. but does anybody remember the helium-filled tubes of the 60's and 70's? to be
honest, i don't actually *remember* them...they were the sort of rumors you'd hear waiting for your
race to start, stories about rich guys who even drilled out their water bottle cages...

 

[Tbgibb]

In article <[email protected]>, "res09c5t" <[email protected]> writes:

>Why not go one better and fill them with helium after evacuation and shave some more grams?
>
>I'm not an engineer but the idea of the walls being in "tension" sounds fishy to me. Hopefully our
>engineers will discuss that for us.

Since you failed to recommend hydrogen it is obvious you aren't an engineer . .
. or chemist for that matter.

Tom Gibb <[email protected]

 

[Mark Freedman]

"B. Sanders" <[email protected]> wrote in message news:<104pa.563833$L1.164874@sccrnsc02>...
> The new evacuated frame tubing is the final frontier for the gram shaver. According to the
> manufacturers, it produces a stronger, yet measurably lighter frame by holding the tubing walls in
> tension (like the spokes of a wheel) due to the internal vacuum. It's especially effective for
> thin-walled large-diameter aluminum frame tubing. Evacuated teel tubing has the added benefit of
> permanent rust prevention (no air means no oxidation).
>
> Has anybody tried one of the early-mid-year 2004 frames built with evacuated tubing (known to
> framebuilders by various brand names like "NoAir", "UltraVac" and "Evac Elite")? I'm curious to
> know more about the special handling characteristics of this new frame technology.
>
> Barry

The cyclists I know who've bought evacuated tubing frames say they really suck. Especially if
they leak.

If you need to save weight, try a Voler-par-la-Nuit(tm) seatless seatpost. But you'll have to
wait until next April 1st. This year's production run sold out immediately.

hth