Optimum tent design – facts versus fallacies and preferences

[Franco]

Franco, are you saying that you believe the Silnylon used by Tarptent to be of equal quality to that used by Hilleberg?
Well it isn't the same silnylon however there are many thousands of TT shelters out there and I never seen a single report of one ripping apart.
There are other manufacturers giving "their" fabric a pet name...

[Joomy]

Franco, are you saying that you believe the Silnylon used by Tarptent to be of equal quality to that used by Hilleberg?
Well it isn't the same silnylon however there are many thousands of TT shelters out there and I never seen a single report of one ripping apart.
There are other manufacturers giving "their" fabric a pet name...

Yes well if we could stop marketers from giving every single feature of every product it's own trademarked name and just tell us the salient details then the world would be a better place.

[north-north-west]

Y'know, Brett, you remind me of a size 16 woman trying to squeeze herself into a size ten designer dress. It just ain't gonna work. Bite the bullet, get rid of some of the excess gear, and get a tent custom made for you.

[ILUVSWTAS]

Y'know, Brett, you remind me of a size 16 woman trying to squeeze herself into a size ten designer dress. It just ain't gonna work. Bite the bullet, get rid of some of the excess gear, and get a tent custom made for you.

[Mountain Rocket]

Franco, are you saying that you believe the Silnylon used by Tarptent to be of equal quality to that used by Hilleberg?

The silnylon used by TarpTent is completely different material (in terms of strength and construction) to the kerlon used by Hilleberg. To say otherwise is disingenuous in my mind.

I know the quote is referring to quality but I just wanted to clarify that in the discussion.

[icefest]

Where can the difference in quality come from? It's been mentioned that Kerlon is triple coated with silicon, but how do you increase the strength of the same polymer?

[Franco]

Robert
Yes I was referring at some other brands but just for curiosity have you seen tests comparing Kerlon 1200 to the TT silnylon ?

[icefest]

Franco,

...have you seen tests comparing Kerlon 1200 to the TT silnylon ?

Do you have some? I'd love to see them.


Correct me if this is a wrong analogy, but the way I understand it is that variations of the same technology have much less difference than the base technologies.
Cf,
1) silnylon, spinnaker cloth and cuben fibre
2) LiMnO2, Alkaline, Li-SOCl 2
3) Paracetamol, aspirin, morphine.

[Franco]

I have seen several comments from manufacturers and "experts" about PU coating weakening the tear strength of silnylon from 30 to 70% .
Neither TT nor Hilleberg use PU on their fabrics for that reason.
However, no I have not seen any test comparing the two.

[Mark F]

There are many nylon polymers - usually you see either nylon 6 or nylon 6,6 with 6,6 generally being considered superior for our sort of fabrics. As well as different polymers the weave can make a big difference. There is a fine balancing act between yarn size (denier) and density of weave (threads per inch in both warp and weft) which can have major consequences for the performance of the cloth and the durability of any finishes such as PU or silicone. Now add in the coating variations (number of coats, thickness and formulation) and the term silnylon becomes totally generic and no guarantee of performance.

From my reading I believe that a little pu in with the silicon seems to produce the best waterproofness.

[Mountain Rocket]

Yes I was referring at some other brands but just for curiosity have you seen tests comparing Kerlon 1200 to the TT silnylon ?

No I have not. Would be interesting indeed. There is not a whole lot known about Kerlon which is interesting considering its origins in the 70s (????? - I know it has been around for a while, longer than me!). I think cost is often touted as the reason.

[icefest]

Hilleberg do publish fabric strength I wonder if Tarptent do too:

[Franco]

No we don't and that is why I was asking Robert how does he know.

[Mark F]

Most of the Nordic manufacturers - Fjallraven and Bergen for instance - used to use polyester base fabrics in the 70's and 80's for better UV performance. You may find the Kerlon moniker has been used on quite different fabrics over the years.

[icefest]

It still is, Kerlon SP is polyester.

[Moondog55]

I thought Kerlon was a polyurethane thread??
I have always thought this because most of my old dynamic climbing ropes were Kerlon.
Perhaps I'm thinking of something else Perlon???

[Moondog55]

https://plus.google.com/photos/10449691 ... 5615479841
I was thinking of Perlon LOL

[Moondog55]

Optimum meaning picking the best compromise between conflicting needs??
I have a question on picking a door size for my winter tent, anybody want to "Pitch-in" and give me their opinions??

Given a 3000mm pole height is 1500mm for a door entry OK and if so what is the best angle for the door vestibule, steep 60 degrees to give most room or more shallow 30 degrees to shed wind or somewhere in between 45??

[icefest]

What shape base? Is this a square-base pyramid?

I'm confused as to the orientation of the vestibule in this :/

[Moondog55]

Regular hexagon
Trying to think of a way to replicate the Helsport Varanger Camp

[icefest]

Ohh, I see.
It looks unstable in crosswind.
If it is only for winter use, I'd make it low (~120cm) and then make a pit below the lowest point. I'd think it's stronger that way.

Is this about right?

[Moondog55]

The trouble with pyramids is the way rain and snow enter the tent when you open the door, the "Camp" model avoids that.

[icefest]

You could put up an internal divider, vertical at the peak of the zip.

[Moondog55]

Except I think I need the whole space. Also the stove will live in the front half section of the tent with the flue going out the top supported by the centre pole.
I could buy something "IF" I had the money. It's the lack of cash that stops me.
But I know I can sew this up once I get the design right in my head, these big tents are a little out of my comfort zone, that's all.
I have plenty of spare poles ( 19mm and /or 25mm) and the correct angle joiners

[Joomy]

Franco, are you saying that you believe the Silnylon used by Tarptent to be of equal quality to that used by Hilleberg?

The silnylon used by TarpTent is completely different material (in terms of strength and construction) to the kerlon used by Hilleberg. To say otherwise is disingenuous in my mind.

I know the quote is referring to quality but I just wanted to clarify that in the discussion.

Clearly I am primarily interested in the performance of any given fabric. For a tent fly fabric that means strength, durability and water resistance. Whatever the technical differences in material construction at the end of the day it's really only important how the fabrics perform. Besides, how different can silicon-coated nylon fabrics really be. Yes the silicon coating quality and quantity can differ, and the nylon type can differ, and yarn gauge can differ and the weave can differ, but that's about it right? To say that any two sil-nylons are "completely different materials" is like saying a Golf and a Focus are "completely different cars", which of course they are but that's not a helpful observation really. They are designed to do roughly the same thing so are directly comparable.

[rcaffin]

I have seen several comments from manufacturers and "experts" about PU coating weakening the tear strength of silnylon from 30 to 70% .

Silicone increases the tear strength of a fabric, while PU coating decreases the tear strength. Known and measured fact. But why?

The silicone polymer impregnates the fibre right through. They call it 'coated', but it is really an impregnation. When subjected to a 'tear', the stretchy silicone polymer tends to spread the load across several fibres, all tightly coupled by the polymer.

A PU coating is on the surface and is much stiffer. When subjected to a 'tear', the PU coating tends to focus all the load on a single fibre - worse than a bare fabric.

Cheers

[Moondog55]

I think that it is dependent on the weight of the polyurethane coating tho, a really thick coating should be stronger as the polyurethane is actually stronger than nylon weight for weight ( all depending of formulation I assume) but my experiments with the home-brew silicon coating tell my that the addition of a layer of silicon to a polyurethane coated tarp does make them stronger.

[Franco]

This is a very recent comment from Michael Glavin, vice president of Sierra Designs.(he previously worked for MSR):

"Because the PU locks down the fibers on a woven fabric it significantly reduces tear strength, and lightweight fabrics can suffer durability issues as a result. Not just abrasion, but tear. Sil/PU fabrics, which not only allow the yarns to float but lubricate them with water shedding silicone goodness, are both light and strong, and resistant to abrasion. These are really good tent fabrics for tents, so long as you accept that they currently cannot be effectively factory seam taped, and do not currently pass fire standards. "

I rather spend 1 hour seam sealing the tent I want than compromise in design or material to have a tent that is factory taped.


Of course as usual to each their own...

Michael's comments at BackpackingLight, gear foum SD quilt thread...

[rcaffin]

There are a few problems with the fire standards:
At the concentrations used, the fabric is not fire-proof
The chemicals used are toxic
The 'research' behind the legislation has been disowned by the author: it was seriously misused
The legislation itself was pushed by the comapny making the chemicals

Another political con.

Cheers