Mm - I should get on with some work, but we do need to make a distinction between Liquid Water and Water Vapour. Obviously they are one and the same (water) but one turns into the other and vice versa and they behave completely differently.
Breathable waterproofs move moisture vapour and resist liquid water (coming from theoutside or inside).
Directional Waterproofs move moisture vapour out AND pump liquid water outwards.
Subtle distinctions -- but they do make the difference betwen staying comfortable of not.
(For the techies - the evaporation of one gram of water absorbs more than 2000 joules of energy - a lot. So sweat evaporation is definitely the most effective means of cooling for bodies - leaving aside jumping in a cold lake. When that gram of water condenses it releases its energy as heat. Wicking moisture away is not always a good thing - you should use sweat to cool you. If you wick it away it can mean that you just have to sweat more to cool down)
Hi Nick, I think it's great that you have taken the time to explain all of this to us! I for one most appreciate it. However, I still have to question waterproofing the pump liner with TX-Direct. I know the Nikwax site says liquid vapour will still pass through the TX.10i elastomer, but how does the pump liner work with a coating of TX Direct?
Also, is there anyway of telling if I have the new or old Parameta A fabric in my shirts, I bought them at the Paramo stand at the Outdoors Show.
Well the moisture just passes between the fibres - the TX.direct just coats the surface of the fibres so it does not inhibit MVT.
The Parameta A is a lot lighter -- smoother texture but no, unless you go and see some in a shop to compare, I don't think you could tell the difference!
Nick, thanks for that. Having a degree and a 20-year career in engineering means I'm not fazed by a simple reciprocal relationship, or the introduction of scientific terminology. I now understand how the 'wet side' of the liner acts to force water away from the body, and this explains why water ingress is prevented. However, I would have thought that the same capillary depression would prevent wicking of body-surface water (aka sweat) into the fabric, by the exactly the same means. Now, I understand that the inner face of the fabric is smooth, and therefore the capillary tubes formed by the fibres will be significantly shorter, but the fact remains that, since the contact angle is >90 degrees (since the fabric is water repellent), the water cannot enter the tubes unless pressure is applied; the water cannot spontaneously enter the tube. Without knowing the dimensions and contact angles involved, I'm not sure what the pressure would be, or if it's reasonable to achieve by simple motion.
Now, if you could engineer a fabric that was hydrophilic on the inner face and hydrophobic on the outer face, you'd be on to a real winner; water sucked into the capillary tube on the inner face, and forced out of the tube on the outer face...some care would be needed around the transition point to prevent force 'dams' blocking the flow; a neutral contact angle region, perhaps.
Given your later posting about body cooling through evaporation of sweat (which is, after all, the purpose of sweat), such a 'wonder fabric' may not be such a great idea. Which means we're back to the suggestion of a wicking base layer, to wick sweat from the body, allowing the sweat to spread over a wider area to evaporate, whilst providing a drier microclimate for the skin, and allowing water vapour to pass through the liner. The pump liner may pass vapour, and prevent the ingress of liquid water, but I still don't understand how it can actively transport liquid water; I suspect it doesn't. Which would explain why Parky finds it uncomfortable to wear his Paramo next to the skin. I think I shall have to borrow someone's Paramo and find out for myself.
Useful explanations/illustrations of capillary depression at:
NickB, thanks for stepping in and trying to put us right.
However a few points:
- If I undersand your correctly, your fibres are not hollow but where two fibres are side by side, the gaps between them act *like* capillary tubes.
That said, suddenly my confidence in intuitive understanding of all this has suddenly "evaporated" (forgive pun) because I now see that surface tension/capillary issues will be greatly affected by complex things like how many fibres per unit volume you have (= "fibre unit density"?) and the weave...
Moreover when you have two large diameter fibres side by side, what happens to water in the gap... Would the water 'prefer' to move to the gap where two smaller diameter fibers are side by side? (ie technically, would the region of water where the larger diameter [hydrophobic] fibers touch each other be at higher pressure than the region of water where smaller diameter [hydrophobic] fibres touch each other?)
Sorry to be dim, but I still dont understand your basic Parameta design... My jackets's *outer* seems to be of *finer* weave (and finer fibers??)than the Parameta liner. Isnt that the *opposite* of what you just described on animal like an otter?
Well so much for theory... what about practice?!
Well I just got my old Paramo jacket out which I have just re-proofed. (Dryclean =>Tech Wash (by hand) => TXDirect (by hand) =>tumble dry => ironed.)
And I put some water on the 'Parameta P', lining, and watched...
Well the first thing that strikes you is that the 'Parameta P' is *so* hydrophobic that the water just bead up! There's not a chance of hit touching the outer shell.
But not content I got my finger and rubbed it in a bit and left it. If you rub it around (as presumably happens a lot when actually wearing a jacket) it can be encouraged to more or less "wet", rather than just "bead".
Well that was 20 minutes ago. Let me have a look...
Nope! Sorry, Nick. No sign of water on the underside (ie my green "polyester microfibre" shell).
I have to say that this doesnt entirely surprise me, because why would water jump off one hydrophobic surface onto another if it didnt have to, let along go through a fine weave of stuff that it hates!
Okay one last experiment. This time I'll soak *both* sides and squish the water right through and then see if the the fine weave on the outer will 'suck the inner dry' (ie 'pump the inner dry as it were...). Quick wipe down of the the green outer shell with hydrophilic rag. Two surfaces nicely touching...
Right that's 5 minutes up. Should be enough. Let me see...
Hmmm... not sure. Yes, the smooth outer surface *has* acquired some beads it didnt have before, right enough. But the inner is still absolutely SOAKING!
Another 5 mins then I have to go.
Okay yes impressive penetration... but damn-it the inner remains drenched!
Conclusion: a) The "pumping" action doesn seem to work if only the liner is wet
b) When both surfaces get wet the pumping action my work a bit...
c) ...But it still leaves the liner soaking wet! (ie it only works rather slowly)
OR
a) Does my jacket have a fault? Is it jacket too old or *too* hyrophobic or something...
Final points. - In hind sight it seems naming both a hydroPHILic (e.g. shirt) layer and a hydroPHOBIC (e.g. jacket) layer as "Parameta <something>" was perhaps confusing and a mistake, no?
- Exactly how come the waterproof trousers can be worn next to the skin, when as discussed elsewhere in this thread, the jackets cant [without discomfort because they dont wick!]
This is brilliant. I still get too hot and sweaty wearing Paramo, but it's nice to know that being sweaty is cooling me. Or at least it would be if Paramo weren't windproof...
Joking aside, thanks to Nick for taking the time to explain the science behind the fabric. Fascinating stuff and I'm going to use it as the basis for a front page article on the site.
shiperton Henerthe 2, I think the problem with your experiment is that there is no body heat to push the mositure through the Parameta.
As I understand it the outer side of the Parameta consists of a very fine pile with the fibres in a V formation. When rain drops reach this surface and work their way between the strands of pile they are forced back out because they reach a point at which they can't form spheres of water, which water naturally does. This is how animal fur keeps animals dry. To work the fibres have to be water repellent so they don't soak up any of the rain.
However Parameta is quite thin and not that tightly woven (you can blow through it) so wind driven rain could pass right through it. The outer layer is to break the force of rain and wind.
I've worn Paramo waterproofs in cool weather for over a decade now, including many months of leading ski tours. I find the trousers very comfortable next to the skin. I have tried wearing the jackets next to the skin in warm weather and I have felt a little clammy, though never wet.
I am going to reply to Shipperton -- just to say that the theory of what works and what works in practice with fabrics are loosely connected.
To obtain a directional pump liner the main process was one of practical assessment of potential fabrics to establish which ones effectively were 'directional' as opposed to shedding water through both faces.
There are other parameters that come into play that I won't go into here for commercial reasons.
Finally the main point is that the process of directional water-repellent water-shedding does work, is used by hairy mammals and birds, and of course Chris Townsend (and a lot of other Páramo users)!
while the technical knowledge team of paramo reading are the thread, i have a practical question. i hope this will be easily answered.
how do i clean (not wash in tech wash) surface mud from my trousers and jacket? this happens from day to day and i don't really want to tech wash the garments every week. i'm told not to use soap anywhere near paramo. i'm reluctant to use a nail brush to scrub the dirt away for fear of disturbing the magic properties. if i hang the garments out in rain it seams to come clean, this rain treatment isn't always practical.
If you don't want to use tech wash all the time then you can use soap flakes (not detergent powders or liquids) I think Boots and some supermarkets sell soap flakes. Otherwise try plain water with a new kitchen sponge with a gentle scourer on it.
All of this technical stuff is getting very confusing.
My own experiences with Paramo have been overwhelmingly positive. A Velez top should be compared with a windstopper fleece. My windstopper fleece is far warmer than the Velez and is far less comfortable - and for that reason I don't wear it anymore. I've not worn my Velez in winter yet but my guess is that it is good enough for most of the year (if not the worst of weather).
I've just come back from the High Pyrenees where my Velez top replaced a fleece and a waterproof jacket. For a little less weight I was able to save a lot of space in my pack. The Velez coped well with wind, rain and hail and was ideal for the High Route (HRP). As I started to desend - and the sun came out - it did get too warm and was taken off but I was able to wear it a lot longer than a windstopper.
This summer I have also been using Kea shirts for the first time. These are easily the best wicking shirts that I have ever used - try them, you won't be disappointed.
in support of andy's thread. i use paramo plus a base layer. i have not been to uncomfortable in very cold wet conditions. if i wear the hood, tighten up the collar, cuffs and bottom of the jacket, i've been comfortable in some pretty nasty conditions. if very cold and wet i add a primaloft top (washed in tech-wash) this, if worn over the jacket, seams to dramitically increase the drying time of a wetted out jacket.
you're getting confused, I think. You should be considering the two sides of _the liner_, not the liner and the shell.
The shell is finely woven to prevent water penetration.
The two sides of the liner are what allow it to perform the capillary-depression-based 'pump' action to repell any water that penetrates the shell.
This pump action is based on the increasing distance between fibres as the distance from the weave backing increases. In an animal (which we can treat as a spheroidal object), this increase in distance is a consequence of a simple circumferential increase. I'm also pretty sure that fibres will clump together, forming coniform channels, and I think you can see this in animal fur. I imagine this latter phenomenon is the main source of channels in the Paramo liner, hence the care in selecting a fabric that behaves in this way, with a longer pile on the outer face, and short-cropped pile on the inner face.
al anon:
I'd start with a short soak in clean, cold water to loosen the dirt, followed by a gentle rubbing. And if that doesn't do it, a little pure soap (_not_ detergent). I'm not sure who told you not to use soap on your Paramo - Nikwax Tech Wash is soap-based.
There's nothing magic about the fabric; it's just a microfibre fabric treated with a water repellent polymer, (or stuff, if you like :-) ). If you rub it or scrub it, you will probably reduce the life of this water repellent treatment, but you can always restore it with TX Direct or Wash-In, either the whole garment, or just in the local spots.
Andy:
sorry if I've dragged it into a technical area; I like to understand things, and I now have a better understanding of how it works - I'm less confused than I was, and may now be tempted to join the ranks of the Paramophiles. I think Nick rather cleverly once called me 'captain paraMoia' on an MtN thread on foot and mouth ;-)
> There are other parameters that come into play that I won't go into here for commercial reasons.
Ah I wondered how you'd react. The conflict between the spirit of scientific enquiry and commercial reality... Fair enough - I guess we cant expect you to give away ALL your secrets on a discussion forum!
So my conclusions are:
1). that the Paramo jackets get a great write up from those in the know. Keep cleaning & re-treating them and they apparently keep the rain out.
2). But they *do* run hot.
The main reason I have persisted with this thread is to try and get to the bottom of *combinations* of clothing - what to do in wet summer weather.
What do Paramo recommend?
What would be really nice would be a full-on article describing pros & cons of the various *combinations* of Paramo clothing in practice, for different types of user and/or different anticipated weather conditions.
I have to tell you, I've had a good old look at the Paramo site and I find it seriously confusing.
Nick, as quick aside on colours... being bit of a birder, I have to say I love my nice soft russle-free jackets - but one huge disappointment is that may of your best gear doesn come in very wildlife-friendly colours! (Many/most dont come in green and the greens used are somewhat dark...)
My suggestion is that either Paramo could write something authoritative or maybe Jon Doran could (with a little help...? ;) )... or both!
One idea would be do a complete week starting at the foot of some tropical mountain. a) "Bloody hot, which shirt shall I wear" and then b) it starts to rain -"Still bloody hot but at first light drizzle..." then c) a downpour
Alternatively profiling different types of user - realistically what layers can they take on and off on a single day...
Or would that be giving away too many commercial secrets? ;)
I don't think Paramo really have a warm weather waterproof option - but then when the weather is warm it doesn't matter if you get wet.
But even in the summer you can get cold and wet weather which is why I mentioned my Pyrenees experience. On one day I had driving rain and hail; in these circumstances the Velez came into its own. Mind you the venting on the Velez works well and I guess would keep you coolish in a real torrent of rain.
I appreciate Captain Paranoia's desire to understand how Analogy works - I was interested too. But the most important thing is the experience of people who are a wearing the stuff and many of them seem to have as good an experience as myself.
I do feel that Paramo gets unfair criticism for being hot, mainly because I don't think they are making the right comparisons. As I've said I would rather have my Velez jacket than my ME Windstopper on virtually any occasion that you would use either.
Anyway, this thread has had something of an effect on me. I've just ordered a pair of Cascada trousers. Winter is coming :-(
Well Bu***R me! I know it works and understand the thory so i'll leave it at That! But i have a prob. In referral to my previous post i can't get the velez as it has a detachable hood and Ten Tors rules states that the hood must be attached to the jacket. and i plan on doing 55 next year so the jacket would fail scruntinerring! would the Aspira jacket suit me needs?
Regarding tropical mountains - I was in Peru last year and walked a trail up by Salkantay and on to Macchu Picchu (not the Inca Trail - a 10 day trek). A few years ago I also did the Kanchenjunga approach Trail and two weeks ago I was in Greece in the Pindos Mountains, so warm is an issue for me too.
In Peru: Warm (low altitude)
Focus on light shirting which is bug proof (Parameta A) and long bug proof trousers. These get worn most of the time - in light showers at 28 degrees C the rain evaporates before you feel cold. Heavy rain requires waterproofs.
I wore my Paramo Analogy jacket over a Parameta A (cool)shirt right up to 5,000m (snow and wind and rain)
For me the combination was OK - but I run hot being very tall.
My wife (very skinny, much smaller, therefore faster heat loss) wore a Parameta S (warm) shirt and Analogy jacket and trousers at higher altitude - fine. Minimum temperature around 0 degrees C - wind gusting to Force 7 at the passes.
Two members of the group were wearing breathable membranes and fleeces. By day 4 their fleeces were completely saturated and they borrowed Páramo kit. Those with Páramo were the driest in the group by a long way ... both in warm and cool conditions.
You do need to select your kit according to your size and girth. Basically the greater your girth relative to your height, the slower you cool down. And the taller you are, also the slower you cool down too. So tall fat people cook and small slim people freeze. There is a huge difference in heat loss between different individuals. There are also differences in metabolism, I understand, but I think that the physique is the key determining factor here for people of similar ages. Could be one reason why Paula Radcliffe was beaten by the very diminutive and light Japanese runner in the marathon in Greece - Paula would have less efficent cooling, being considerably taller(old people don't produce as much heat, I understand - but that's a different issue).
(For the techies here, it's basically down to surface area to volume ratio - the bigger your surface area relative to your volume, the faster you cool - bigger people cool slower because surface area increases quadratically and volume and weight increase cubically. Mice lose heat very fast and have to eat huge amounts relative to their body mass -- elephants need big ears to cool down)
