wrote in message ...
In article ,
Bill Grey wrote:

You can theorise all you like I can only comment on what I actually
experienced and still do.

As I posted, my statements are also based on measurement, personal
experience and other people's experience. Whether you have been
just lucky, have never stressed Goretex as much as we have, or
simply been unobservant, I can't say.

It works fairly well (I use Goretex boots), but nothing made by
mortals works perfectly.


Regards,
Nick Maclaren.

Having walked my dog pretty well every day for the best part of 10 years, in
all weathers, in long wet grass, mud snow and rain, often had the bottoms
a of my trouser legs soaked but my feet never were wet, My hillwalking days
I enjoyed, and always had Gortex lined boots - no problem.

Bill

In article ,
PeterC wrote:
On Wed, 23 Jan 2013 14:19:52 +0000, Gordonbp wrote:
On 23/01/13 13:45, RJH wrote:

I would add, and how to put this delicately, it does depend upon how
sweaty you are.

Goretex boots work well for me, but the clothing is rubbish because I
sweat 'a bit' given the slightest movement. By pure luck I've come by a
Rohan 'barricade' coat that works for me.

I second that - having had several Goretex jackets and getting damp
underneath from sweat, I found eVent and my Rab Latok now breathes well!

Hadn't heard of these two but I haven't liked Goretex since it first came
out - something to do, IIRC, with it being described as "breathable".
As it happened I had a long break from walking and when I started again
almost all of my kit was inadequate - 30 yo leather boots /and/ my feet had
changed quite a bit.
With some doubts I looked for modern kit and was pointed towards Paramo. I
does seem to work well, unlike the modern Scarpa boots which aren't as good
as my first leather pair from 40 years ago - nut the Scarpa do have Goretex
in!

I used to use Goretex for serious walking, but also found it sweaty.
It is vaguely breathable, but only in very dry (and warmish) conditions.
But I moved to Paramo because Goretex was too cold on its own climbing
uphill, and a jersey underneath was far too hot! Paramo may not be
as waterproof, but is more breathable and generally comfortable.

I haven't yet exposed to Paramo to really wet conditions (which means
3+ days of heavy, driving rain, sleeping out), but it seems to be OK
in moderately wet ones.

For boots, at least Goretex doesn't leak like a sieve after the first
3 days of sodden conditions (as over-flexed leather does), and I am
not expecting miracles (i.e. feet that stay actually DRY under those
conditions). While I suspect that it is stitching that causes the
leaks (it is definitely NOT trickle-down), I can't rule out the
pumping effect. But the amount is livable with.


Regards,
Nick Maclaren.

In article ,
Bill Grey wrote:

Having walked my dog pretty well every day for the best part of 10 years, in
all weathers, in long wet grass, mud snow and rain, often had the bottoms
a of my trouser legs soaked but my feet never were wet, My hillwalking days
I enjoyed, and always had Gortex lined boots - no problem.

I have never had any trouble under such mild use, either, nor did
I with other fabrics and materials. Most of them work tolerably
well day-by-day, if you can get them at least dryish overnight;
it is the third and subsequent days out in conditions that make
most dogs want to stay indoors that distinguish the waterproofness
of materials.


Regards,
Nick Maclaren.

wrote in message ...
In article ,
Bill Grey wrote:

Having walked my dog pretty well every day for the best part of 10 years,
in
all weathers, in long wet grass, mud snow and rain, often had the
bottoms
a of my trouser legs soaked but my feet never were wet, My hillwalking
days
I enjoyed, and always had Gortex lined boots - no problem.

I have never had any trouble under such mild use, either, nor did
I with other fabrics and materials. Most of them work tolerably
well day-by-day, if you can get them at least dryish overnight;
it is the third and subsequent days out in conditions that make
most dogs want to stay indoors that distinguish the waterproofness
of materials.


Regards,
Nick Maclaren.

You seem determined to play down my experience with my Gortex boots/trail
shoes, you comment of "mild use" is quite patronising seeing as you don't
really know the conditions in which they were used.

Very wet is very wet.

Your remark "... it is the third and subsequent days out in conditions
that make most dogs want to stay indoors that distinguish the waterproofness
of materials." .....sums up their use quite accurately.

You go your way, Ill stick with my truth.

Bill

On 23/01/2013 09:59, wrote:
In article ,
Peter Clinch wrote:
Bad phrasing on my part. What I'm getting at is that in order to /be/
staurated you need over a 4m water column providing pressure, and that
other words, the hydrostatic head will be maintained precisely because
the pore structure cannot get saturated until you exceed it.
The pore structure won't be saturated however much the face is.

Well, maybe. I accept that is true under simple conditions, but
real life isn't that simple. Inter alia, one of the reasons that
Goretex says that its fabrics must be kept clean is that 'dirt'
can act as a flux. Also, rubbing causes transient overpressure
which can cause 'breakthrough' - and, once that has happened and
both sides of the pores are wet, the surface tension effect is
(mostly) lost.

There is also the question of what the overpressure is for pouring
rain being driven by a force 7 gale :-)

I'm cross-posting this to uk.rec.motorcycles, because they are rather
familiar with the problems of high wind speeds and rain.


Its claims are nonsense (a
water molecule is NOT much larger than a steam molecule), and my
understanding is that the hydrostatic head is due to hydrophic
material.

It's surface tension, but you can't break the surface tension until you
exceed the hydrostatic head, which you won't do because it's too big.
So it won't leak until you've got a lot more pressure forcing the water
through than will happen in practical application.

I am not convinced, though I have been unable to measure any flow.
What I have seen is water on one side, in conjunction with rubbing
and probably dirt cause darkening and a feeling of damp on the
other. This matches with what I know of the physics involved.

Most examples of "leaking" are condensation on the other side, which is
remarakably difficult to get rid of.

That is true. As we both know, perfect waterproofing is a complete
waste of time for UK conditions, for that reason alone.

If it's easy to measure percolation through goretex then it would fail
the hydrostatic head tests that Gore use as the basis of their guarantee.

Not at all. Those tests almost certainly require a maximum level of
leakage, which can be regarded as negligible. That's reasonable, but
NOT the same as claims of perfect waterproofness.


Regards,
Nick Maclaren.


See embedded.... Andy

On Wed, 23 Jan 2013 20:28:25 +0000, Andy Champ
wrote:

I'm cross-posting this to uk.rec.motorcycles, because they are rather
familiar with the problems of high wind speeds and rain.

If you manage to find any that still ride in the rain.

On Wed, 23 Jan 2013 09:59:59 +0000 (GMT), wrote:

Also, rubbing causes transient overpressure
which can cause 'breakthrough' - and, once that has happened and
both sides of the pores are wet, the surface tension effect is
(mostly) lost.

I had, somewhere, the catalog of an outdoor supplier. They said that for tent
floors, such-and-such head (10 meters? 20? I forget, but it was it was a lot
more than I would have expected) was a reasonable lower limit to keep the floor
dry-ish in rain.

Moving around on the tent floor would "work" the water through; dirt from below
would make it worse. This agrees with the above... (They also said to put a
cheap tarp or plastic sheet under it to help keep away water, dirt, and holes.)


Thomas Prufer

On Thu, 24 Jan 2013 08:16:33 +0100, Thomas Prufer wrote:

On Wed, 23 Jan 2013 09:59:59 +0000 (GMT), wrote:

Also, rubbing causes transient overpressure
which can cause 'breakthrough' - and, once that has happened and
both sides of the pores are wet, the surface tension effect is
(mostly) lost.

I had, somewhere, the catalog of an outdoor supplier. They said that for tent
floors, such-and-such head (10 meters? 20? I forget, but it was it was a lot
more than I would have expected) was a reasonable lower limit to keep the floor
dry-ish in rain.

Moving around on the tent floor would "work" the water through; dirt from below
would make it worse. This agrees with the above... (They also said to put a
cheap tarp or plastic sheet under it to help keep away water, dirt, and holes.)

Thomas Prufer

A groundsheet that's adversly affected by dirt...! Now there's good design!
Never had any trouble with the ripstop and PVC(?) floors in the old (70s)
tents, including one morning when there was a streamlet under the tent.
--
Peter.
The gods will stay away
whilst religions hold sway

Grimly Curmudgeon wrote:

On Wed, 23 Jan 2013 20:28:25 +0000, Andy Champ
wrote:

I'm cross-posting this to uk.rec.motorcycles, because they are rather
familiar with the problems of high wind speeds and rain.

If you manage to find any that still ride in the rain.

Don't judge others by your own low standards.

--
ogden

990SMT - bouncy orange tractor
GSXR1000 - vintage sports-tourer

Andy Champ wrote:

On 23/01/2013 09:59, wrote:
Well, maybe. I accept that is true under simple conditions, but
real life isn't that simple. Inter alia, one of the reasons that
Goretex says that its fabrics must be kept clean is that 'dirt'
can act as a flux. Also, rubbing causes transient overpressure
which can cause 'breakthrough' - and, once that has happened and
both sides of the pores are wet, the surface tension effect is
(mostly) lost.

There is also the question of what the overpressure is for pouring
rain being driven by a force 7 gale :-)

I'm cross-posting this to uk.rec.motorcycles, because they are rather
familiar with the problems of high wind speeds and rain.

I've worn Goretex kit in rain at up to 160mph and stayed dry.

In "high wind speeds", I tend to worry more about what's in front of me
than the science behind why I'm not soaking wet.

--
ogden

990SMT - bouncy orange tractor
GSXR1000 - vintage sports-tourer

"ogden" wrote in message
...
Andy Champ wrote:

On 23/01/2013 09:59, wrote:
Well, maybe. I accept that is true under simple conditions, but
real life isn't that simple. Inter alia, one of the reasons that
Goretex says that its fabrics must be kept clean is that 'dirt'
can act as a flux. Also, rubbing causes transient overpressure
which can cause 'breakthrough' - and, once that has happened and
both sides of the pores are wet, the surface tension effect is
(mostly) lost.

There is also the question of what the overpressure is for pouring
rain being driven by a force 7 gale :-)

I'm cross-posting this to uk.rec.motorcycles, because they are rather
familiar with the problems of high wind speeds and rain.

I've worn Goretex kit in rain at up to 160mph and stayed dry.

In "high wind speeds", I tend to worry more about what's in front of me
than the science behind why I'm not soaking wet.

--
ogden

990SMT - bouncy orange tractor
GSXR1000 - vintage sports-tourer

Nice and dry when my son drove his Bluebird up to that speed and clear so he
could see where he was going ;-)

My Bonneville doesn't go out in the rain, which means it hasn't been out
very much :-(

Mike

--

....................................

I'm an Angel, honest ! The horns are there just to keep the halo straight.

....................................

Wear Altbergs.

On 24/01/2013 07:59, PeterC wrote:
On Thu, 24 Jan 2013 08:16:33 +0100, Thomas Prufer wrote:

On Wed, 23 Jan 2013 09:59:59 +0000 (GMT), wrote:

Also, rubbing causes transient overpressure
which can cause 'breakthrough' - and, once that has happened and
both sides of the pores are wet, the surface tension effect is
(mostly) lost.

I had, somewhere, the catalog of an outdoor supplier. They said that for tent
floors, such-and-such head (10 meters? 20? I forget, but it was it was a lot
more than I would have expected) was a reasonable lower limit to keep the floor
dry-ish in rain.

Moving around on the tent floor would "work" the water through; dirt from below
would make it worse. This agrees with the above... (They also said to put a
cheap tarp or plastic sheet under it to help keep away water, dirt, and holes.)

Given that in my lightest tent you can almost see through the
groundsheet, a little protection from abrasions wouldn't be amiss.

I once thoroughly cleaned a tent for a trip to Australia and didn't
reproof the groundsheet. It took a while to discover it was porous. :-(

A groundsheet that's adversly affected by dirt...! Now there's good design!
Never had any trouble with the ripstop and PVC(?) floors in the old (70s)
tents, including one morning when there was a streamlet under the tent.

Those kind of tents are OK provided you have an infernal combustion
engine to lug them about. The modern stuff is so much lighter.
--
Phil Cook

On 24/01/2013 14:09, YTC#1 wrote:
Wear Altbergs.

Who of course have access to Magic Leather which never suffers the same
problems with waterproofing as the merely high quality leathers all
other manufacturers are stuck with using...

Personally I wear Yeti gaiters, and that works very well for keeping my
feet dry in leather boots. They're not cheap but as well as keeping
your feet dry they also preserve the boot's upper from a lot of the
horrors that walking through acid bogwater all day tend to visit upon
them. Fairly mad for DIY, gardening or m/cycling though, and if I
really wanted dry feet for those I'd wear wellies. Quite often for
walking too...

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net http://www.dundee.ac.uk/~pjclinch/

On 24/01/2013 14:45, Phil Cook wrote:
On 24/01/2013 07:59, PeterC wrote:

A groundsheet that's adversly affected by dirt...! Now there's good
design!
Never had any trouble with the ripstop and PVC(?) floors in the old (70s)
tents, including one morning when there was a streamlet under the tent.

Those kind of tents are OK provided you have an infernal combustion
engine to lug them about. The modern stuff is so much lighter.

In the late 80s I switched from a Force Ten to a Saunders Sapcepacker.
Both 2 man tents, one 7 Kg, the other 2 Kg. Does make a bit of
difference carrying it about.

Of course the Force 10 groundsheet was as tough as they get, but having
said that the Spacepacker has never leaked, including a time in Norway
when I went to sleep over thawing snow and woke over thawed snow (i.e.,
water).

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net http://www.dundee.ac.uk/~pjclinch/