A Visual Paradigm for Windshirts - Multiple Axis of Understanding.-Rev 0
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Paul Hatfield
(clear_blue_skies) - F
Difference from specs on 02/23/2014 00:55:52 MST Print View

I don't understand how the air permeability that you measured for the Rab Alpine Jacket (111 CFM) can be so off from the spec for the Pertex Equilibrium fabric that it is constructed of (~ 20 CFM). Any thoughts?

Edited by clear_blue_skies on 02/23/2014 00:58:04 MST.

eric chan
(bearbreeder) - F
Re: Difference from specs on 02/23/2014 02:14:03 MST Print View

i think it just shows that unverified "specs" should be shoved down where the sun dont shine

this isnt climbing gear where specs need to be accurate for safety, or en-rated sleeping bags where EU rules require actual testing standards

quoted manufacturer specs can be wildly inaccurate ... and honestly much of the time have more to do with marketing mumbo jumbo

ive always found it quite funny personally when there are whole threads dedicated to arguing how this or that gear is better on paper according to the manufacturer specs, when you dont know if they are even accurate

also remember that a fabric that has seen usage can be quite different from when it is new

;)

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Difference from specs on 02/23/2014 12:00:55 MST Print View

Serge

Eric correctly pointed out a variable which we have no information on. All other garments I tested were new.

When was your garment purchased and what was the summary profile of its use / care?

Edited by richard295 on 02/23/2014 12:43:47 MST.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
RAB Alpine jacket CFM mystery solved? on 02/23/2014 17:54:00 MST Print View

I was curious as to why the “coffee filter” air permeability tests that Wim Depondt conducted on a NEW RAB Alpine seemed to indicate comparable breathability to the RAB Boreas. Wlm Depondt tested approximately 75 CFM for both. My lab tests showed the RAB Boreas was 68.7 CFM but, the USED RAB Alpine tested 111 CFM.

I took multiple micrographs of both fabric sides of the USED RAB Alpine. The following micrographs are 5.0mm and 1.4mm Field of View clearly indicating that a very-thin-clear PU (VTC PU) coating was added to the inside of the fabric during manufacture:

b


3


There were no visible wear spots on the outside of the fabric to indicate abnormal use. Consequently, it is plausible that the NEW air permeability could have been comparable to the RAB BOREAS when new, but, degraded to the 111 CFM level, from the VTC PU coating reduction, with 20 - 25 days of normal use.

A VTC PU coating on the inside of the Gossamera fabric (Arcteryx Squamish) has been used by Arcteryx since the 2009 model year. My hypothesis may also apply to this garment.

Edited by richard295 on 02/25/2014 13:24:56 MST.

Dale Wambaugh
(dwambaugh) - MLife

Locale: Pacific Northwest
Re: RAB Alpine jacket CFM mystery solved? on 02/23/2014 18:11:38 MST Print View

68cfm sounds pretty breezy let alone 111cfm. From my experience with other PU coated fabrics, there isn't much of a coating there. Do they mechanically abrade it like some other fabrics?

Any specs on the OR Ferrosi fabrics? They seem similar to some Supplex shirts given the Darth Vader test.

Serge G.
(sgiachetti) - M

Locale: Boulder, CO
alpine use on 02/23/2014 18:16:16 MST Print View

I'd estimate that's I've worn the alpine 20-25 days since last winter, mostly back country skiing with a pack on. It might have gotten thrown in the wash & dwr'd with a couple other garments, but I'm not certain.

eric chan
(bearbreeder) - F
interesting on 02/23/2014 20:20:09 MST Print View

now thats a VERY interesting question IMO

how does a windshirt breath after a decent amount of usage

i can say with my trail wind it doesnt seem to breath much better ...

i suspect it all depends on the fabric and the coating

hmmmm

;)

Ross Bleakney
(rossbleakney) - MLife

Locale: Cascades
Re: A Visual Paradigm for Windshirts - Multiple Axis of Understanding.-Rev 0 on 02/25/2014 13:26:31 MST Print View

Getting back to your original questions Richard:

I would say that the first three (breathability, water resistance and weight) are the most important to me. Other factors are nice, and will play a part in my purchasing decision, but those three are by far the most important for me. For example, I care about durability, but own Propore (I just know they are fragile). I want to save money, but I've bought (and will continue to by) Cuben. If there is some magic windshirt that does well in all three categories, then I'll spend lots of money, even if is fragile.

With that in mind, I suggest a table with at least those three items. It can have more (your call). Along with that, I would make a chart with breathability on the X and water resistance on the Y (these can be swapped if you prefer). Then I would represent weight with a bubble (the bigger the bubble, the heavier it is). I think this would be fairly intuitive. For example, if you were displaying rain jackets, than an Event jacket shows up in the upper right quadrant (very breathable and water resistant). A Propore jacket is a little bit closer to the axes. But the Propore jacket has a much smaller circle. (I've used rain jackets for my examples, even though I know this is for comparing windshirts).

The other advantage of this approach is that you can draw a line to designate something. For example, you could have a line designate what is generally considered "waterproof". Beyond that, a lot of people won't care if a jacket is more water resistant. Likewise, a line for the 35 marker on CFM.

Roman Vazhnov
(joarr) - MLife

Locale: Russia
water absorbtion on 02/25/2014 13:30:28 MST Print View

I wonder - are there polypropylene windshirts? I have found only Rohan Ether and Klattermusen Tjatse.

Jeff Jeff
(TwoFortyJeff) - F
Re: A Visual Paradigm for Windshirts - Multiple Axis of Understanding.-Rev 0 on 02/25/2014 18:31:07 MST Print View

I don't think this has been done before because it's not necessary. If you want to display these four attributes, it's best to just list them out.

The most obvious problem is that the chart has lines that imply, for example, that an item has more water resistance as it gets lighter. From an engineers perspective, if a given line represents a given product, it implies that the product's attributes exist anywhere on that line. We know that this isn't true because all of the attributes shown are fixed, not functions of each other.


I do enjoy your CLO and CFM charts though :)

Edited by TwoFortyJeff on 02/25/2014 18:33:13 MST.

Nick Gatel
(ngatel) - MLife

Locale: Southern California
Re: A Visual Paradigm for Windshirts - Multiple Axis of Understanding.-Rev 0 on 02/25/2014 20:50:35 MST Print View

How important are ALL four components?

We can't have everything at the same time -- or you can't have your cake and eat it too :)

For me (1)breathability and then(2)durable are most desirable.

(3) Next comes weight.

(4) Water resistance is last, because it will suffer if my first two items are of most importance.

I like the latest axis chart, which shows the older Houdini meets my important criteria, which I can anecdotally confirm.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Rev. 3 - A Visual Paradigm for Windshirts - Multiple Axis of Understanding on 02/25/2014 21:01:53 MST Print View

Jeff correctly pointed out that the Rev. 2 chart could be interpreted that an item has more water resistance as it gets lighter.

This was a limited data set artifact. The simplest clarification was to add the Wild Things WT 1.0 EPIC fabric windshirt.

1.3

2.1

3

4

Edited by richard295 on 02/25/2014 23:21:43 MST.

David Chenault
(DaveC) - BPL Staff - F

Locale: Crown of the Continent
Re: Rev. 3 - A Visual Paradigm for Windshirts - Multiple Axis of Understanding on 02/26/2014 09:49:13 MST Print View

Thanks Richard, keep up the good work.

I do wish Wild Things would put a more refined hood on the tactical windshirt.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
WT 1.0 Mods - A Visual Paradigm for Windshirts on 02/26/2014 11:37:14 MST Print View

David,

Thanks for the positive feedback.

For bushwhacking in perpetually damp conditions, I have found the WT 1.0 fabric without equal. If a fabric doesn't test well for my intended purpose, I just get rid of the garment. If I keep it, then I inevitably find a few tailoring issues to moan and groan about. After that, I make the DIY tailoring changes to optimize the garment for my needs.

Tailoring Issue 1: Like you, I found the hood lacking. It’s only cut for "under helmet" applications and there are no options to adjust its volume or head position. To correct this, I always wear a wide brim hat with it; the hat has an internal adjustable head band size. It allows me to customize the WT 1.0 hood volume and position the way I want it and keep it in place under the hat.

Tailoring Issue 2: I want to close the wrist aperture when heat needs to be retained and loosen it up, along with the neck zip, to facilitate chimney effect cooling when needed. I rarely take off my pack to make clothing adjustments. I added Velcro wrist closures.

wrist

Edited by richard295 on 03/07/2014 00:00:13 MST.

Paul Hatfield
(clear_blue_skies) - F
Balancing breathability/water resistance on 02/26/2014 13:55:24 MST Print View

Balancing Breathability/Water Resistance

Graph of Air Permeability (CFM) x Hydrostatic Head (mm H2O) for the garments that Richard tested.

This is my take on interpreting the data.

Edited by clear_blue_skies on 02/26/2014 14:01:13 MST.

KEN LARSON
(KENLARSON) - MLife

Locale: Western Michigan
BD Alpine Start Hooded Jacket on 02/26/2014 17:18:39 MST Print View

This data might interest some:

The Alpine Start is at 40 CFM

FROM:
Brad Curkendall
Black Diamond Equipment

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: BD Alpine Start Hooded Jacket on 02/26/2014 17:42:38 MST Print View

Ken,

Thank you for the information!

Needless to say but, the CFM spec is near optimal for aerobic activities; what is the companion HH spec?

Also please inquire if both of these specs are based on Black Diamond's tests or Scholler's tests?

Edited by richard295 on 02/26/2014 23:08:57 MST.

KEN LARSON
(KENLARSON) - MLife

Locale: Western Michigan
Re: BD Alpine Start Hooded Jacket on 02/26/2014 17:50:16 MST Print View

Richard .....I did not inquire, an over sight!

Paul Hatfield
(clear_blue_skies) - F
Black Diamond Alpine Start Hoody air permeability / hydrostatic head specs on 02/28/2014 17:27:10 MST Print View

I received this response from Black Diamond:
-----------------------
Thanks for getting in touch with us. The jacket is 40 CFM (cubic feet per minute) which is technically 40 CFM/M2 (cubic feet per minute per meter squared) but the industry simply refers to this as CFM. This is testing done by Schoeller and tested by BD. It is a stretch fabric and should increase the CFM slightly when stretched.

The hydrostatic head is approx 500 mm. It is treated with Nanosphere but does not have any coating that is generally required to get higher hydrostatic performance.

Kim Hall | Black Diamond Equipment

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Black Diamond Alpine Start Hoody air permeability / hydrostatic head specs on 02/28/2014 18:08:51 MST Print View

It is false that, “40 CFM (cubic feet per minute) is technically 40 CFM/M2 (cubic feet per minute per meter squared)”

The ASTM D737 standard on page 3 says, "11.1 Air Permeability, Individual Specimens—Calculate the air permeability of individual specimens using values read directly from the test instrument in SI units as cm3/s/cm2 and in inch-pound units as ft3/min/ft2, rounded to three significant digits."

Kim may have the English representations and the SI representations mixed up. If so, a 40 SI value equals a 78.74 CFM value. As a general rule, EU companies (Schoeller is Swiss) spec their values in SI format.

Edited by richard295 on 02/28/2014 20:17:09 MST.