Hi all,

I have been studying tent designing for some time. I started with Roger's notes DIY Tents and have read notes on several tent designs at MYOG section at backpacking.net. My goal is a sub-2 pounds tent but so far the goal has been illuding me.

Obviously, for such a light tent the design has to be such that it should use minimum material yet provide 4 season worthy protection. I think the Nemo Morpho meets that requirement. But Morpho is a three season tent with a packed weight of 5.7lbs(!)

http://www.nemoequipment.com/nemo08-morpho-tent

Take a look at Morpho. It has a excellent design. I especially like the convertible vestibule. OK, it is not usable for wet cloths, backpack and shoes (you can always carry a waterproof pack, keeps your cloths dry, put shoes in trash bag) but the convertible vestibule offers space for cooking or the fly over it can be tied for a superb mesh ventilation. Also you can see that fabric lenght between two pole sleeves is very less; that gives very stable tent.

SO how do you get it under 2lbs:

>Replace WPB fly with 1.35oz silnylon fly
>Replace mesh with nanoseeum
>replace airbeam, the foot pump, the spare bladder, and the bladder repair kit with prebent nanolite Poles or CF poles

Now this is single wall tent but I think by adding several features it can be used in winter with minimum condensation.

>Wear VBL over full body
>Make the front door out of propore:- you can buy a Driduck poncho for that.
>Add a 'condensation curtain':- basically a a silnylon curtain hanging from the front pole over your chest so that moisture from your breath moves out through the propore door.

I still have to do some modification to the design and lot of calculations. I would appreciate some constuctive feedback.

it looks a lot like a stephenson tent. you may want to consider picking up a used one of those instead of hacking up the nemo. its a tried and true design

I know this doesn't directly address your question but here is some more info I've found on the Stephenson's tents. You can check them out at www.warmlite.com. If you aren't too tall they have a new shorter version called the 2C at 2 lbs 10oz. They say it is two feet shorter than the standard model so overall length should be about 110". Price is $499 versus $385 for the Morpho. There is a review of this tent by one of our members at

http://www.viajarapie.info/routes/europe/nordkalottleden_gear_analysis.htm

David, I didnt mean I was buying Nemo. I am 'hacking' its design.

Yes, Stephenson 2c is using a very similar design. I will try incoperating best features of both these tent in my design.

Ryan, I had that link but lost it. Thanks for the link.

Huzefa, if I understand you correctly, your plan is to use the design of the Morpho, not to modify one.
Trying to visualize your version of it, I end up with , as David suggested, the Warmlite design but with a side entrance and a built in vestibule.
A few comments

Add a 'condensation curtain':- basically a a silnylon curtain hanging from the front pole over your chest so that moisture from your breath moves out through the propore door.

That may work but likely you will end up with a shower curtain

Make the front door out of propore
I would question the durability of propore ( abrasion and tear strength) when used as tent material, in fact I don't know of any tent that uses this material.

CF poles
CF offers great strength for weight ratio, but has two major weaknesses:
poor lateral pressure and the older type of glue still used in some of them will crack below freezing (note that the Stealth Fighter Jet uses CF , so some type of CF can perform below freezing)
However at the moment putting CF poles under that much stress at low temperature is not ideal. Note that Roger is using mostly straight segments and hubs.
Franco
Sorry, I forgot to refresh the page before I posted, if nothing else I did get the design bit.

Edited by Franco on 04/13/2008 19:21:43 MDT.

Franco, thanks for the comments. You understand me correctly.

That may work but likely you will end up with a shower curtain
I am working with some novel ideas to prevent that.

I don't know of any tent that uses this material.
hey someone has to expriment. sure it is not durable but may be it has some some tear strength. I can reinfrorce the seams with silnylon.

I probably wont use CF. I like prebend poles, something you cant do yet with CF.

Some progress:
>removing mesh vestibule to save weight. Such a small vestibule is not much useful. Instead a better idea is to make a double silnylon floor. You go inside with all your wet shoes and pack. cook. zip off the upper floor and pack your wet stuff in it. You get a nice clean place to sleep.

Edited by huzefa on 04/13/2008 21:35:49 MDT.

Vestibule
Have a look at the Lightwave T0 Ultra for some hints
http://www.lightwave.uk.com/en/tent_t0ultra.php
Franco
Morphing the Morphed Morpho

The condensation curtain is not a new idea and it works quite nicely. The Nemo Tenshi used to have this as an option (see my review on this site). Back then, the Nemo was constructed of eVent which made the tent a magical condensation-free gem. The condensation curtain was a good idea but wasted fabric on a tent with this caliber of breathability. However, I think it makes really good sense in a tent that has little or no breathability in the fabric if there is a good vent placed neear the top. It essentially restricts the condensation coming from the breath (your major issue in winter) to a small area, keeping your bag drier and making it only necessary to ventilate really well in one area. I think it's a rock solid idea.

Hufeza- I hope to see your ideas come together at some point. I think you're pulling together some creative ideas for sure and the end result might be pretty cool. At the very least, your ideas have generated some interesting conversations!

There are some great reviews on this site that might help in your planning. Specifically, I'm thinking about the Fibraplex carbon tent pole review or the Outdoor Designs Summit Extreme that used the Easton FX poles. I love carbon tent poles and I've had good luck with them, even with high winds on Rainier or in heavy snow loads. I think they're a viable option, but not all would agree.


Have a good one,
Doug

Franco, I looked at T0 Ultra. I am surprised that the manufacturer hasnt put more pictures on its website. But I got the idea. The vestibule is too small; good for cooking but not enough space for gear. I can extend the tent to make space for the vestibule but I would need 3 poles for the same stability.

Doug, thanks for the nice comment. I enjoyed reading your review of Nemo Tenshi.

While the steep sidewalls increased usable space, they also increased side deflection.

Thats the precise reason why I am working with a 2-pole tunnel design rather then a 2-pole dome like Nemshi. Also, the tighter curvature of poles in a tunnel give it more strenght and stability in wind.

I have made some more modifications in the design:
>I am chopping of the end at the front. Take a look at Atko to get the idea. This place can be used for venting.

>Also I am thinking of glueing light wool to the silnylon curtain. Wool is the most vapour absorbant faric I have found till now. If someone has a better idea let me know. The vapour now has two options: either vent out or get absorbed by wool.

Doug
I have a hard time believing that a silnylon condensation curtain works, but I am only guessing

CF poles and tunnel tents
Still waiting for tentmakers like Hilleberg and Fjallraven to use them as standard issue (or even as an option) before I get too excited about them.
BTW I suspect that the poles on a Morpho type design are under more lateral stress than on a cross pole design like the Summit Extreme or ID MK.
Franco

Hi Franco,

On the Nemo it was just regular nylon, not silnylon. So it was essentially a reduction of the available space in the tent for moisure- it kept it to a smaller area. The curtain came down at the neck and angled up to the large vents on top of the tent. A lower door cracked open created airflow straight up to the vents. The curtain essentially removed the lower body and about 2/3 of the tent from your breath.

It's an interesting idea but like I said, in an eVent tent, it was pretty unnecessary.

Franco, from my understanding, poles in tunnel do have more lateral pressure then a tent like summit extreme but not enough to affect it if the lenght of fabric between poles is optimal. On the hand summit extreme is less stable in high wind particularly if the wind is coming from sides.

Doug
If I could have used bold on the word silnylon I would have....
My point was that you cannot just put a piece of silnylon hanging down and hope that it will work. However if you create an air flow (as it is done in the Nemo) and use a non fully waterproof fabric, than it should do the job.
As you stated, using eVent would negate the need of that, maybe now that GE is not doing as well as expected they will donate eVent to some other caring and loving corporation.
Got to go, a pig just flew past my window.
Franco

Hufeza,

You really are quite wrong here. I've tested many, many tents and in many hairy places with crazy storms and I can tell you that nothing is more stable in the wind than a Rab Summit Extreme. The sloping walls and low ceiling height make this the ultimate high winds tent, in my opinion. Besides that, you have perfectly place guy-outs and also the ability to achor directly to the mountain. If I were to camp at high camp on K2, this would be my tent.

A tunnel tent (also known as a hoop tent or a Scandanavian tent) is a great compromise because it offers great usable space for the weight. You get a larger interior space when using poles as hoops, rather than crossing them. The most stable tents, however, use poles that cross. The 4 pole Mountain Hardware EV3 is a stellar high wind tent and the much smaller Summit Extreme accomplishes a similar result with an extremely low profile design and two crossign poles. These will also handle snow load much better than a tunnel tent because tunnel tents have larger flat areas on top (but this might not be such a big deal in the Himalayas).

I've used the Hilleberg Nallo 2 and Kaitum extensively in the field. Although not the best, these are still excellent performers in high winds- my Kaitum has been in several 60mph+ storms at altitude and done very well. But it does this because of extensive use of guylines and bomber fabrics and reinforcement. The design is a compromise, though, that gives you much more usable space for the weight and I've found the compromise to be sufficient for any storm I've put them through.

Our Bomber Tents Review Summary and reviews of many of these tents might be a good place for you to go to develop your ideas.

That said, I would guess that the fabrics you're selecting would fail far before the structure of the tent would become an issue. Once you get a tent into high winds, you'll start to see what I mean- I've seen tents shredded to pieces on Rainier- these environments are harsh.

Doug

Well, yes, the Extreme may be very stable, but please note:
* Only 700 mm high in middle, almost no height at sides and ends
* "This shelter is not designed for UK backpacking in wet conditions"

So while I don't disagree about "If I were to camp at high camp on K2, this would be my tent", I do question whether two people, or even one person, would want to spend a couple of weeks living in this tent on a long trip. A different market!

> The most stable tents, however, use poles that cross.
I am will respectfully disagree here, provided that you compare equal-size tents. I have built and used both domes and tunnels, and for equivalent weight and space I have found the tunnel much more reliable. The poles on a dome are just so long in comparison. I have had the centre of a dome flex down to thump the sleeper inside in the tummy - but it was a 3-man dome.

> handle snow load much better than a tunnel tent because tunnel tents have larger flat areas on top
Ah ... not all tunnels have flat areas on top, and not much more than a dome anyhow. Some tunnels have a deliberate peak on top to shed the snow. Not many, I agree, but one reason for that is the expectation of a high wind where these tents get used!

There was a bit of a gale here all night.

> because of extensive use of guylines and bomber fabrics and reinforcement.
* Yes, definitely, on the guylines bit. But guylines are very light, and far more reliable than 'free-standing'.
* Yes on the need for careful design with reinforcement at the right places. Hey - this is a mountain tent after all.
* "Bomber fabrics" - not so sure. In my experience what usually goes first are the guylines (or stakes really), immediately followed (in time) by the long poles. Even silnylon will handle an awful lot of wind IF (IF) the poles don't move. But let the fabric start to flap loosely and ... trouble. If the poles collapse ...

OK, that's my experience and 2c worth.

Cheers

Huzefa this is turning into a saga but I am enjoying it...
"gluing wool on the silnylon..."
Bibler did something similar on the inside of their "Todd Tex" fabric (Todd Tex was a play on words with Gore Tex, same thing...)
From memory it was referred to as "Nextex" and not a specific other name. I have one of their tents and that fuzzy stuff works, but I don't know what is made off. (it traps moisture so that id does not drip down. remember my shower curtain comment ?)
Wind/ snow resistance.
I think that a three/four pole Gothic Arch tunnel tent is a bit different from a standard two pole continuous arch.
In a similar way a cross pole tent is a bit different from a five pole geodesic design.
Up to a point a two pole tunnel can work (Stephenson's/Hilleberg) and so can a two cross pole design (Bibler,ID,Rab) but the first needs a lot of tension and the second needs a good dose of cloustrophilia (loving enclosed spaces)
Franco
Roger that Rab shelter is not as low as stated. it's about 860mm high
Bomber fabrics. I think Doug was referring to the Propore door.
BTW, I am not trying to teach Roger or anyone how to suck eggs, it's just another point of view. As I stated before I wonder why that design that Roger has shown above is not used by the "big ones" . It certainly makes sense to me.

Edited by Franco on 04/14/2008 23:20:28 MDT.

Well there you go Roger! Cool- this proves that it's not all dependent on design. It's not a matter just of tunnel or dome, but by the design, materials, etc. There's moe than one way to make a great winter tent!

And you're 100% correct that the Rab is notthe best all-around tent- a very specific design. But it's certainly an amazing tent in horrible conditions- namely the wind conditions that Hufeza was referring to.

Cheers,
Doug

I am a bit skeptical of whether there is a normal-size sub-2 pound tent that you can truly call a full 4-season tent. Even if it's a tunnel!

Buy hey, somebody please prove me wrong here.

Edited by jbrinkmanboi on 04/14/2008 23:24:50 MDT.

It's Huzefa's idea. I hope he makes a prototype to share with us! But right now, it's an idea only.

The lightwave tents Franco provided a link to earlier also use gothic arch poles, and come in various sizes, flavours of pole layout, material weight and fly lower edge cut to suit different conditions and occupant numbers. If Huzefa is going to the himalaya, he might want a partner to hold the other end of the rope and help keep the tent warm at night.

http://www.lightwave.uk.com/en/tents_overview.php

Worth a look for weight comparisons even if you are going to MYOG.

Personally, I don't much care for thin whippy poles on winter tents and have settled for the sub 2 pounds golite Hex3 (now the shangri-la) because I travel with a partner these days. This is a bomber teepee design with good wind shedding properties and a massive 55 square foot living area tall enough and airy enough to run a petrol stove inside.

Edited by tallbloke on 04/15/2008 04:01:08 MDT.