Neoprene thickness - or not?

"Dr. Yak" <DrYak@nospam.com> wrote in message
news:nnEWd.43851$755.1046@lakeread05...
> Your examples of making no difference would be true if neoprene were
> either a perfect insulator or a perfect conductor. It is somewhere in
> between, so more thickness makes more warmth. Metal line suits are a
> marketing ploy.

IS it a case of more thickness = more warmth though? I accept what you say
regarding perfect insulators and perfect conductors which of course neoprene
is not. Is the thermal conductivity of neoprene such that doubling its
thickness makes an appreciable difference to any one individual, or do we
need to quadruple the thickness?

However what is more important - the thickness of the neoprene or the ease
(or otherwise) with which water flows through your suit? A 3mm suit can be
worn with comfort if it is a tight fit. An equally-tight fitting 7mm suit
may be so restrictive of movement that a less snug fitting is required in
order to be practical. Water flows through it more easily, and so the
greater warmth afforded by the neoprene is lost simply because more heat is
lost that way. A hood worn with either would help, partly because it reduces
losses from your head but also partly because it discourages water entering
the suit around your neck. Given all of these counfounding factors, is the
thickness of neoprene THAT important?

Without having any real data as regards the metal-lined suits I too am of
the opinion that they are marketing ploys. I can see how they may even be
colder than suits without metal.

Ken

"Dr. Yak" <DrYak@nospam.com> wrote in message
news:nnEWd.43851$755.1046@lakeread05...
> Your examples of making no difference would be true if neoprene were
> either a perfect insulator or a perfect conductor. It is somewhere in
> between, so more thickness makes more warmth. Metal line suits are a
> marketing ploy.

IS it a case of more thickness = more warmth though? I accept what you say
regarding perfect insulators and perfect conductors which of course neoprene
is not. Is the thermal conductivity of neoprene such that doubling its
thickness makes an appreciable difference to any one individual, or do we
need to quadruple the thickness?

However what is more important - the thickness of the neoprene or the ease
(or otherwise) with which water flows through your suit? A 3mm suit can be
worn with comfort if it is a tight fit. An equally-tight fitting 7mm suit
may be so restrictive of movement that a less snug fitting is required in
order to be practical. Water flows through it more easily, and so the
greater warmth afforded by the neoprene is lost simply because more heat is
lost that way. A hood worn with either would help, partly because it reduces
losses from your head but also partly because it discourages water entering
the suit around your neck. Given all of these counfounding factors, is the
thickness of neoprene THAT important?

Without having any real data as regards the metal-lined suits I too am of
the opinion that they are marketing ploys. I can see how they may even be
colder than suits without metal.

Ken

> IS it a case of more thickness = more warmth though?

Should be - neoprene's got lots of little bubbles trapped in, the air in
those bubbles will warm up and air is of course a very good insulator of
heat. There are of course lots of other factors as you mention - the fit
needs to be good, linings may make a difference (the smooth lining around
the seals should help flushing for example), and the metal linings *may*
make a difference. I think the thing about them is that they will reduce a
certain kind of heat loss (radiated heat), but i don't think that would be
the main source of heat loss in the water and so how much value it is i'm
not sure.

In the end I suppose you just go with whatever works for you.

David

> IS it a case of more thickness = more warmth though?

Should be - neoprene's got lots of little bubbles trapped in, the air in
those bubbles will warm up and air is of course a very good insulator of
heat. There are of course lots of other factors as you mention - the fit
needs to be good, linings may make a difference (the smooth lining around
the seals should help flushing for example), and the metal linings *may*
make a difference. I think the thing about them is that they will reduce a
certain kind of heat loss (radiated heat), but i don't think that would be
the main source of heat loss in the water and so how much value it is i'm
not sure.

In the end I suppose you just go with whatever works for you.

David

> IS it a case of more thickness = more warmth though?

Should be - neoprene's got lots of little bubbles trapped in, the air in
those bubbles will warm up and air is of course a very good insulator of
heat. There are of course lots of other factors as you mention - the fit
needs to be good, linings may make a difference (the smooth lining around
the seals should help flushing for example), and the metal linings *may*
make a difference. I think the thing about them is that they will reduce a
certain kind of heat loss (radiated heat), but i don't think that would be
the main source of heat loss in the water and so how much value it is i'm
not sure.

In the end I suppose you just go with whatever works for you.

David

> IS it a case of more thickness = more warmth though?

Should be - neoprene's got lots of little bubbles trapped in, the air in
those bubbles will warm up and air is of course a very good insulator of
heat. There are of course lots of other factors as you mention - the fit
needs to be good, linings may make a difference (the smooth lining around
the seals should help flushing for example), and the metal linings *may*
make a difference. I think the thing about them is that they will reduce a
certain kind of heat loss (radiated heat), but i don't think that would be
the main source of heat loss in the water and so how much value it is i'm
not sure.

In the end I suppose you just go with whatever works for you.

David

> IS it a case of more thickness = more warmth though?

Should be - neoprene's got lots of little bubbles trapped in, the air in
those bubbles will warm up and air is of course a very good insulator of
heat. There are of course lots of other factors as you mention - the fit
needs to be good, linings may make a difference (the smooth lining around
the seals should help flushing for example), and the metal linings *may*
make a difference. I think the thing about them is that they will reduce a
certain kind of heat loss (radiated heat), but i don't think that would be
the main source of heat loss in the water and so how much value it is i'm
not sure.

In the end I suppose you just go with whatever works for you.

David

> IS it a case of more thickness = more warmth though?

Should be - neoprene's got lots of little bubbles trapped in, the air in
those bubbles will warm up and air is of course a very good insulator of
heat. There are of course lots of other factors as you mention - the fit
needs to be good, linings may make a difference (the smooth lining around
the seals should help flushing for example), and the metal linings *may*
make a difference. I think the thing about them is that they will reduce a
certain kind of heat loss (radiated heat), but i don't think that would be
the main source of heat loss in the water and so how much value it is i'm
not sure.

In the end I suppose you just go with whatever works for you.

David

"David Walker" <stuff@scuby.co.uk> wrote in message
news:d0fatl$fjr$1@wisteria.csv.warwick.ac.uk...
>> IS it a case of more thickness = more warmth though?
>
> Should be - neoprene's got lots of little bubbles trapped in, the air in
> those bubbles will warm up and air is of course a very good insulator of
> heat. There are of course lots of other factors as you mention - the fit
> needs to be good, linings may make a difference (the smooth lining around
> the seals should help flushing for example), and the metal linings *may*
> make a difference. I think the thing about them is that they will reduce
> a certain kind of heat loss (radiated heat), but i don't think that would
> be the main source of heat loss in the water and so how much value it is
> i'm not sure.
>
> In the end I suppose you just go with whatever works for you.

Ultimately, yes of course. I just wonder whether, in the same way that a
metal lining appears to be a marketing ploy, so is the increasing thickness
story in order to get us to buy more neoprene than we need!

Indeed there are more bubbles in thicker neoprene, but these bubbles get
less important with depth as they are squeezed out of existance. There is
likely to be very little radiated heat as a proportion of the whole, given
the grand opportunities for heat loss by conduction and where a good
conductor of heat (any metal in this context, even the worst of them) forms
one of the layers.

Ken

"David Walker" <stuff@scuby.co.uk> wrote in message
news:d0fatl$fjr$1@wisteria.csv.warwick.ac.uk...
>> IS it a case of more thickness = more warmth though?
>
> Should be - neoprene's got lots of little bubbles trapped in, the air in
> those bubbles will warm up and air is of course a very good insulator of
> heat. There are of course lots of other factors as you mention - the fit
> needs to be good, linings may make a difference (the smooth lining around
> the seals should help flushing for example), and the metal linings *may*
> make a difference. I think the thing about them is that they will reduce
> a certain kind of heat loss (radiated heat), but i don't think that would
> be the main source of heat loss in the water and so how much value it is
> i'm not sure.
>
> In the end I suppose you just go with whatever works for you.

Ultimately, yes of course. I just wonder whether, in the same way that a
metal lining appears to be a marketing ploy, so is the increasing thickness
story in order to get us to buy more neoprene than we need!

Indeed there are more bubbles in thicker neoprene, but these bubbles get
less important with depth as they are squeezed out of existance. There is
likely to be very little radiated heat as a proportion of the whole, given
the grand opportunities for heat loss by conduction and where a good
conductor of heat (any metal in this context, even the worst of them) forms
one of the layers.

Ken