Wot makes a tent 4 season?

[pjclinch]

It does seem to suffer from condensation to a certain extent as not as breathable as other tents meant for kinder weather but can live with this.

Unless you have cotton canvas or single-skin Goretex or similar, very few modern tents are at all breathable. The flys are generally all impermeable. Where condensation will go up or down if all else is equal is the amount of moist air that can escape through holes and gaps, but if it does it'll take its heat with it.
You choose, you lose..

yep agree - the Skorpion 2 inner is rather light on mesh.

It's the flys that don't breathe at all. "Solid" inners are usually a very light ripstop with a DWR coating, and while not enabling as much airflow as mesh are still quite breathable. However, the DWR coat brings up a possible issue because while an untreated fabric will typically let moisture soak in and then evaporate the DWR will prevent that so you get droplets forming, and exactly the same feature you want in place to make drips from the fly roll off rather than soaking in to fabric is the feature you don't want to let internally generated moisture get out... The actual breathability of the fabric, measured in how much air can pass through it in a given time, doesn't change but a fabric with a DWR coat is generally clammier in a humid atmosphere. If the moisture is vapour it'll go through, but if it's a condensed droplet (and especially in the cold it tends to be) the DWR will tend to keep it that way.

Again, you choose, you lose..

Pete.

[horizon]

Surely a decent tent designer could design a tent where all of the poles were straight

Well they did, it was called an A frame. But then domes came along. And the rest, as they say, is history.

I did a couple of short trips last year in my Vango Force Ten Mk 2. It is indeed beautifully strong and simple. For a couple of trips where I had to go by car, I used an old Lichfield A frame with extension. Again, so simple and so inherently strong and indeed repairable.

[pjclinch]

The spirit I think is a gothic arch type of tunnel tent I think. Where did it fail? No doubt on a crimp but I'd think it's on the top of the lower pole. I personally think the gothic arch isn't a strong design. I prefer rounded tunnel tent poles as I suspect there's a more even stress on the poles..I might be wrong though.

I'm not an engineer, but my feeling is with gothic arches that doing it for strength has got the wrong end of a stick. A pointed arch is lighter and stronger than a round arch for forces normal to the point, which is great for holding up a cathedral roof, or indeed static snow loading on a tent, but I'm not convinced it makes something better against high winds hitting from the side. As they do. And it's all very well pitching tail in to the wind but as that deep depression tracks over during the night the wind direction will change...

Of course, another thing about them is that the sides can be steeper so you get more effective volume inside, though nobody making them seems to use that as an argument. In any case, this is part of my preference for Hille's tunnels where everything slides through from one side easily and with minimal faff and a result that seems to be strong enough.

Undoubtedly the crimp of the pole is a poor design and imho you should avoid tents with these poles.

All other things being equal, yes, but then again all things tend not to be.
My Spacepacker has crimped poles because back then stuff like modern DAC poles where a lot of work has gone in to making the joins strong weren't about. There again the overall pole diameter is well in excess of most lightweights so that in turn makes it stronger. And my Spacepacker has been in some genuinely hideous conditions where the pole has warped a lot, but it's never broken. It's all very well saying "crimps are weaker, avoid all crimps", but there again 8.55mm are weaker than 9mm poles are weaker than 10mm poles, so where do you draw the line?

Pete.

[Sweep]

Surely a decent tent designer could design a tent where all of the poles were straight

Well they did, it was called an A frame. But then domes came along. And the rest, as they say, is history.

sorry, maybe wasn't clear. I meant straight but with bending of said straight poles.

[pjclinch]

Surely a decent tent designer could design a tent where all of the poles were straight

Well they did, it was called an A frame. But then domes came along. And the rest, as they say, is history.

sorry, maybe wasn't clear. I meant straight but with bending of said straight poles.

TBF this seems to be the rule rather than the exception.
For an encore decide whether you want pre-bent curved poles or straight poles that bend (I think there are arguments both ways)

Pete.

[Tangled Metal]

By crimps I mean where the outer pole is stopped inwards to form three tabs of metal punched into the joint pin. Those tabs are effectively held by very small pieces of metal still attached to the pole near the end. How can they fail to be a weak design?

Diameter of pole has no effect on this it is the crack propagating to the end of the pole such that the pin pulls out and it effectively folds at the joint. The jagged end where the crimps fail then goes through the outer of the pole sleeve.

I've had crimped poles that have lasted and survived storms too. That doesn't make the design a significant weak point. Now there's alternatives so imho crimped poles should be left out of a tent design.

I think the whole point of tunnel tents is how they deform to survive. Side gust energy is dissipated by the deformation. It's how a mate's tunnel survived when another mate's quasar full on mountain tent snapped a pole.

I think the rounded arch of a tunnel deform evenly with a more even stress along the pole. The variation in the gothic arch poles means the stress isn't evening distributed I suspect which will have many effects possibly such as pole failure when a round pole would survive. All speculation on my part.

[Sweep]

For an encore decide whether you want pre-bent curved poles or straight poles that bend (I think there are arguments both ways)

Pete.

lost me there am afraid with the encore comment.
I meant poles which have entirely straight sections but where the whole thing is bent for erection.
Not sure I have a tent where all of the poles are like that.
Am willing to put up with any limitations that might give the tent - I only sleep in them.
With everything straight spares and repairs should be a doddle - something you can sort on site without any bodging.

[horizon]

Surely a decent tent designer could design a tent where all of the poles were straight

Well they did, it was called an A frame. But then domes came along. And the rest, as they say, is history.

sorry, maybe wasn't clear. I meant straight but with bending of said straight poles.

No I did understand you correctly but was making the (obvious) point that we did have absolutely straight poles in the past which of course were strong and replaceable. If we go to rounded tent forms, then yes, the shape of the poles becomes as issue.

AFAICS, all the poles I have on my tunnel tents are essentially straight but get rounded during putting the tent up - they are short enough to allow for that stress and I have presumed that that is why you have several joined together, not just for ease of packing*. But some curving has undoubtedly taken place and I don't know now whether that is a consequence of usage or just something I missed or on one tent rather than another. We replaced a section of fibreglass poles on a largish dome last year and what Vango supplied were both generic and absolutely straight.

Like you, I don't like the idea that something that is intrinsically straight has to bend and is only OK if you don't bend it too far. Back to my original point, the ergonomic gains of dome and tunnel forms has come IMV at the cost of some strength (in this case, poles). I presume that geodesic domes are only as strong as the poles that support them.

* I could be wrong about this.

[pjclinch]

For an encore decide whether you want pre-bent curved poles or straight poles that bend (I think there are arguments both ways)

lost me there am afraid with the encore comment.
I meant poles which have entirely straight sections but where the whole thing is bent for erection.
Not sure I have a tent where all of the poles are like that.
Am willing to put up with any limitations that might give the tent - I only sleep in them.
With everything straight spares and repairs should be a doddle - something you can sort on site without any bodging.

An option is have the sections pre-curved so they're already in the right shape when you pitch the tent, which removes stress of bending them any time you pitch. Spares would match the curvature, as could repair sleeves. US brand Warmlite has been doing that for a long time (their prices are in the Hilleberg range), but it makes them more expensive and more awkward to carry.

You choose, you lose...

Pete.

[pjclinch]

Back to my original point, the ergonomic gains of dome and tunnel forms has come IMV at the cost of some strength (in this case, poles). I presume that geodesic domes are only as strong as the poles that support them.

Rather than thinking of poles as isolated objects we need to consider the effect of them working together as a structure (in a tunnel a loosely connected structure, but still a structure). It's a lot harder to break a pole with wind when it's supported by other poles as is the case with a geodesic, or if the pole moves out the way as is the case with a tunnel.

You're ultimately looking at maximum strength for a given weight, and I doubt a couple of very stout poles will ultimately hold up as well as a structure of slimmer ones. AIUI space-frames are strong for their weight.

[pjclinch]

By crimps I mean where the outer pole is stopped inwards to form three tabs of metal punched into the joint pin. Those tabs are effectively held by very small pieces of metal still attached to the pole near the end. How can they fail to be a weak design?

Diameter of pole has no effect on this it is the crack propagating to the end of the pole such that the pin pulls out and it effectively folds at the joint.

But a larger diameter pole is inherently stronger so less likely to crack in the first place.

We're all in agreement that no crimping is good, but where is the right compromise between strength and weight when it comes to diameter?

"It depends"...

My point is that while it makes sense to avoid bad practice like crimped poles if all else is equal, all else typically isn't and you can say the same for e.g. PU coatings that significantly weaken flysheets, and yet PU flys have been successfully used in far more extreme situations than I guess anyone here is likely to encounter.
So with so many different points of compromise don't get too hung up on the poles as long as they're not made of cheese.

Tandeming pals of mine did a tour of the Western Isles with a cheap Eurohike dome with glass poles. We were pitched next to similar at Thurso where its owner was just finishing LEJoG. As someone that gets far too precious about certain aspects of tent design I'm aware of a tendency to get far too precious about certain aspects of tent design...

Pete.

[Tangled Metal]

Our only broken pole was Alloy. Our fibreglass poled tents have lasted well. One small 3 man tent with fibreglass poles has even survived a bit of snow loading and subzero temperatures which apparently they can't take.

For car camping, well camping with campervan, we prefer fibreglass poles. I think 3 tents/awnings have them.

We tend to pick the tent for activity. Car camping isn't as potentially demanding as self supported cycle touring or backpacking. Cycle tours we have a helsport lofoten pro extended porch 3 man tent. Best DAC poles. Small section n poles with friction fit pins I believe. 3.1kg I think and a pack size that fits into an ortlieb pannier!

We have a three man vango with fibreglass poles for last minute tent camping. Larger family tents of which he fibreglass poled tent works better for us due to it pitching a lot faster than the steel poled one we also own. I family car camping we think other factors are more important than pole material or design for us.

Tent design choices can be overthought at times. I've pitched in force 5 or 6 storms under a tarp head up by carbon fibre trekking poles. Same conditions that saw a hilleberg atko being flattened such that the gusts blew the flysheet into the open mouth of the amazingly still sleeping occupant! Other nights I've slept through storm in a 3 season tunnel with no guylines just the flysheet and pegging points to hold it down and up. My mate had a very bag night in his quasar tent over 3 times the cost of mine. I pitched mine better I thin, the same with my tarp night out.

[Carlton green]

Given Tangled Metals well informed comments in his many posts above would it be true to say that how you use what you have got makes a lot of difference? Sometimes even a crucial difference? Of course there are limitations but I’ve found the following is true: it ain’t what you’ve got that matters most it’s what you do with it. Situations vary - it’s not an all cases rule - but in my experience much might be achieved with little.

Wot makes a tent 4 season? It seems that part of the answer is skilled - or unskilled - use.

[pjclinch]

Given Tangled Metals well informed comments in his many posts above would it be true to say that how you use what you have got makes a lot of difference? Sometimes even a crucial difference? Of course there are limitations but I’ve found the following is true: it ain’t what you’ve got that matters most it’s what you do with it. Situations vary - it’s not an all cases rule - but in my experience much might be achieved with little.

Wot makes a tent 4 season? It seems that part of the answer is skilled - or unskilled - use.

Very much fair comment IMHO. Outdoor hobbies are full of cases of people using stuff that they allegedly can't possibly use to do what they're doing... I'm pretty sure my wife and I aren't the only riders that see "unsuitable for laden tourers" notes on NCN maps as more of a challenge than a warning!

Pete.

[Tangled Metal]

I once got told off for not wearing big, heavy boots on a footpath over the tops of Yoke and Ill Bell iirc. It was a cold winter's day with a deep layer of fresh snow. We'd come up the steep side from the valley with ice axe out just in case. We met an elderly couple wearing b1 boots with c1 crampons sat on a summit. They left as we got there, wading almost knee deep in the fresh, powdery snow.

They were wearing balled up, traditional walker's crampons which from my past experience don't help much in deep snow. I was wearing trail shoes and waterproof socks. Toasties warm and dry. Plenty of grip on the track down which was compressed snow and ice. Trail shoes give me better grip than boots. I could easily trot down at pace in shoes. The truth is knowledge and experience meant I knew what was right for me in those conditions. I also laughed at their attempt at telling me off as I jogged off at twice their speed and more sure footed too.

My point is that knowledge and experience made me know that conventional wisdom and advice didn't apply to be in those conditions. Fitness, knowledge, experience and dare I say skills meant more than slavishly following received wisdom on kit choice.

It's common in bushcraft circles to say that the most important thing to havei n the outdoors is knowledge . It weighs nothing and you always have it with you.