Aluminum vs Carbon Fiber Tent Poles

[Stuart Murphy]

Yes, those Syclone poles are interesting – have been a round a few years now (2 or 3?). Doesn’t seem like Easton or manufacturers have any interest in making them available mainstream (maybe they have to be designed for the specific tent rather e.g. than pre-bending aluminium poles to suit as necessary) — I don’t recall seeing them advertised on any non-Easton tents — if that’s the case, then I can imagine the analysis, lay-up etc. would be costly. I think Easton advertised them as comparable in cost to aluminium poles (with no mention of huge lay up costs for a tent manufacturer)… The lack of take up/interest/transparency in the industry is weird.

[Roger Caffin]

Hi Stuart

Like I said, first define strength.
Yes, I use stiffness. It is very appropriate for tarps of course – see the bendy pole in Glen’s photo posting 3473423 (above, this page). It is also quite appropriate for tunnels: a stiff pole is not going to distort much at high wind.

Yield strength is different – that’s when everything goes ‘bang’. CF has plenty of that sort of strength too. Usually enough that stiffness is the main factor.

I was hoping the Easton guy might come to the party and provide you various samples.
Ah – what Easton guy is that???? If you are referring to the failed attempt to get Easton to make my tent – they only supplied 7.5 mm CF poles. Anyone else – nope.

put it on the corporate card
ROTFLMAO – WHAT corporate CC?

or I’d be willing to contribute to costs.
If you want to send me some samples of CF tube of different diameters, I can test them same as all the other CF and Easton poles I have tested. PM me for that.

Cheers

[Sam Farrington]

Glad this thread was brought forward. That is a nice video of a tent in high winds.

Easton says the Syclones are not carbon fiber, but are made of unidentified “composite” materials wound from multiple directions into a tube—allowing them to flex under force and return to shape. The construction certainly sounds like filament wound carbon fiber. Not sure what they have that is stronger than carbon fiber. Wasn’t it CF that was conceived to be a material connecting a satellite in stationary orbit to the ground?

Easton also says that the Syclones are more resilient, and illustrates this with a pole flexed into a circle with a tight diameter. The problem with that is a tent supported by such poles could be blown almost flat onto the ground. Then ‘You will get wet,’ to use Roger’s expression, and you might as well roll yourself up in the tent rather than pitch it. With stiff enough poles, the tent should resist flattening, and maintain a reasonably upright shape. Certainly, the design of the tent, as well as the use of guylines, will also help to keep the shelter upright, not to mention limiting vibration and shaking.

The less flexible, or stiff, that a given material is, the sooner it should break applying the same force in the same way. So it is arguably weaker in that sense. I think the challenge is to find a material that is stiff enough to keep things upright, with good design and support, but also resist breakage under force. Somewhere there should be a ‘sweet spot’ between stiffness and flexibility that works best for a given tent design.

Somehow I doubt that one of us trailhounds is going to come up with all the math to correctly formulate the above, and suggest that simply applying force in the same way to different pole tubes until they break has been more helpful. Daryl once posted on BPL a link to a thread on the old Kitebuilder site that illustrated a set-up for this. It was a long and thoughtful thread on ferrules, including internal vs external.

Somehow, I also doubt that the ability to make pretzel shapes out of your tent poles is what is holding MSR’s tent with Syclone poles upright (sort of) at 60+ MPH winds in the above video.

Here’s an excerpt that may be of interest from “Hiker rescued after windy night on Mt. Washington,” an article in the April 25th issue of the “Conway Daily Sun:”

“Shortly after midnight on Sunday, Alexander Slavic, 27, of the Czech Republic made a 911 emergency call for help after sustaining damage to his tent during a period of relentlessly high winds. … The call was prompted as broken and bent tent poles poked holes in the tent, partially collapsing it and letting in snow and bitter winds.”

He was well equipped, survived pretty much intact, and hiked out on his own, but with SAR folks for company.

[Stuart Murphy]

Roger – my bank account won’t play ball just at the moment but I will contact you in 1-2mths – would be good to have a quick chat re the tests (and limited availablilty of poles) – then I’d be happy to contribute say $50 Aus… maybe we can get something happening.

 

I thought the Easton guy who chimed in earlier in the thread was likely to contact you. Maybe we can try that angle again then too. Anyway, will be in touch.

Cheers

Stuart

[Roger Caffin]

Why does it seem to be my role in life to pop bubbles all the time?

To the best of my knowledge:

Some years ago Easton had a go at making composite tent poles: an aluminium core with fibre wound over the outside. The commendable idea was to blend the best of both worlds.
The Syclone poles were released in 2013, so they date internally a year or two before that.
They were a bit of a disaster.

To be sure, there was some mismatch in material properties between the fibre and the aluminium, but that was not the real problem. There was also a huge difference in the coefficient of thermal expansion between the fibre and the aluminium, and that killed the concept. In very crude terms, in very cold weather the aluminium core shrank far more than the fibre wrap, so the core effectively separated and dropped out of the middle. The strength was all gone.

The product died of course. You will find Google hits to the word Syclone, but most of them date back to the initial wild enthusiasm from some parts of the credulous media and the retail world.

Yes, I have played with a few sections, back when they were released.

Now try to find ‘Easton tent poles’ on the web. You will get hits from lots of retailers who have old stock to get rid of, but not to any site owned by Easton. Well – let’s just say I could not find one anyhow. You draw your own conclusions.

Cheers

[Stuart Murphy]

Sam – yeah stiffness not always = to strength (as measured by a break, say) I guess. Same would be the case for the Nemo inflated airbeams (they seem to have discontinued the Morpho range except the bivvy?)similar concepts used by other manufacturers) although they claimed those beams were stiffer than “standard” poles (most manufacturers use quite narrow poles though) — they should be able to flatten and pop up.

The metal ferrules in the carbon fibre poles are going to be the weak points (talking about the thicker good Easton ones not random poles) and while I can imagine that these stiffer poles (all things equal) will reduce the likelihood of the ferrules failing (due to decreased bending/stress on them at a given load) it is all very dependent on the pole arc, tent geometry etc I am guessing.

I would like to see an objective lab test to give the numbers for a couple of standard pole lengths/arcs and more videos of tents being flattened in front of a wind machine to give a more practical insight into what these figures imply about performance in the field (how different aluminium poles behave, their failure modes as well as various composite poles).

I do think I’m dreaming if I expect anyone to actually be able to do that kind of testing though… Unless Roger manages to find the corporate card for a wind machine and several copies of a tent to trash (and let’s make it 1 tunnel, 1 semi and 1 geodesic for good measure)…

Re the syclones held flat to the ground — if it doesn’t break and the stitching doesn’t pop at least the tent can pop up if it’s just a few isolated gusts. Otherwise, probably the same effect as a pole through the fly – you will get wet. Anyway – based on those syclone videos the poles look stiffer than standard aluminium.

 

[Stuart Murphy]

I thought syclone lives on (and despite my earlier comment no non Easton tent manufacturers have used them) are in use eg. some MSR tents.

https://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0ahUKEwie157_lPTUAhWBWbwKHYsuA3IQFgguMAI&url=https%3A%2F%2Fwww.outsideonline.com%2F2110771%2Fwe-climbed-mt-baker-test-msrs-new-mountaineering-tent-line&usg=AFQjCNGpmnzzwTLogOxpP9Mf9_kaPnXfLw

Hadn’t heard any reports other than what the manufacturer propagated.

 

[Roger Caffin]

Well, yes, but since the Founder died, I think MSR has lost its way. Today they are driven by lawyers, accountants and a few marketers. They lack the technology base they once had.

very high winds blowing steadily at about 35 miles per hour, and gusting up to 50 miles
Very high????

Access: a glorified pop-up. Poles NOT threaded into fly.
Remote: far better, but expensive and heavy, and poles not threaded.
AdvancePro2: expensive, cramped and poor ventilation.

Biased? Who, me? Nah, just into survival.

Cheers

[Edward John M]

So what type of poles are the Easton Carbon FX?

I too was hoping the Easton guy was coming back to spruik and explain the whole gammut of pole technologies

[Michael F]

Yeah the easton dude said the carbon fx poles were currently being used on everest somewhere and he would trust them for expedition usage …hopefully all of that is true because it sounds very interesting

[Roger Caffin]

We have used CF poles on our tents for the last N years, where N is large (I don’t remember). We use them in the snow, and on 3 month long walking trips around Europe. No problems.

Our poles were generic CF arrow shafts from Asia – but a genuine multi-layer 2D wrap design, NOT cheap pultruded. Since there are not many companies in the world making CF arrow shafts (a big machine is needed), it is likely that there is not much difference between brands.

Now, wrapped fabric CF poles are a slightly different matter. They are not as strong as the genuine wound 2D ones, but they are getting better.

Cheers

[Sam Farrington]

It is a shame that BPers have been deterred from CF poles because of the garbage that has been sold for CF on the market.  After using some of the garbage, I was also discouraged, but after corresponding with Roger and devising some break tests, found that both Victory and Gold Tip produce filament wound arrow shafts, SOME of which are as strong as the Easton .344  alloy Nanotubes, but much lighter.   Disagree strongly with the Easton rep’s comment on this thread that, “any attempt to use an arrow or some off-the-shelf generic carbon tubing would produce marginable [sic] results at best …”    Yes, their CF poles are strong, but they are a lot heavier than the ones Roger refers to as “wound 2D,” meaning that the filaments are wound in varying directions and layers.  Googling CF tubes will bring up vendors of filament wound tubes that are much stronger than wrapped fabric or pultruded CF, but are very expensive.  The wound CF arrow shafts, which are mass produced for archers, made it possible to produce flexible CF dome poles that are not only lighter, but also at least as strong as the Eastons, so there is no longer any need to carry extra pole sections; just the same type of short repair over-tubes that typically come with any flexed pole tent.  I’ve had zero breakage.

The upright tubes that are used with pyramid and similar tents are another story, and agree that the flex of the one shown on this thread creates an unnecessary risk of breakage.  A slightly larger diameter pole of alloy or CF will be much stiffer.  There are several threads on this and the MYOG forums that address sourcing these poles or the CF to make them, so I won’t try to rehash them.  Because a pole for a mid will not be subjected to anywhere near the same abuse as a trekking pole, it can be quite a bit lighter than a CF trekking pole, and still be reliable for its purpose.  Again, it is the marketers that have sold thinner and more flexible poles for uprights who have given CF a bad name.  And as for those new four season tents from MSR, not only do they NOT have the strength of CF, but they are also way heavier than what we are looking to use for Backpacking LIGHT.

Anyone wishing to produce flexible CF poles for dome or tunnel tents is welcome to PM me with an email return address for detailed info. For ‘mid’ poles, there is much info available on MYOG and the GEAR forums for both ready-made and materials.  We don’t have to settle for heavy and inferior gear.

[Roger Caffin]

Disagree strongly with the Easton rep’s comment on this thread that, “any attempt to use an arrow or some off-the-shelf generic carbon tubing would produce marginable [sic] results at best …”

Well, he is hardly likely to endorse the cheaper alternatives, is he?

For a practical demo of the strength of generic 2D wrap arrows, read “When Things Go Wrong”. 100 kph wind all night in a snow storm, but the tent barely moved.

Cheers

 

[Anonymous]

Has anyone seen any of the new Al alloys (like the Kobe one) on the regular market anywhere, or are these being solely bought up by industry and government at this point?  I wonder how good of a poles these would make in comparison to current CF?

[Roger Caffin]

Last I saw, Kobe was making preforms. It is a long path from there to thin-wall tubing like tent poles, although they have had quite a few years now.

My suspicion is that the stuff is a shade pricey. Like out of sight for our applications. Having said that, Fate will have them release such tubing at an affordable price, tomorrow.

Cheers

 

[Anonymous]

Like any of the really good stuff (like Dyneema and Spectra), the military and corporate sectors are probably buying up tons of the stuff. Which doesn’t seem to make it any cheaper for us.

[LA Hiker]

Anyone have an Easton Carbon 2P tent? I got one, and it is missing the poles. Need the dimensions (total length, and the length of each section).

Have to make replacement poles, deciding between carbon and Aluminium.

[Sam Farrington]

If you are lucky enough to find the dimensions for the EMP tent poles, you would obtain around the same weight and strength for both the Easton alloy .344 and CF poles.  Quest still sells the .344, but have replaced the Easton CF with something they claim is just as strong and light.  Suggest first ordering just one section of the CF from Quest to see for yourself.  The Easton .340 is stronger than the above two, but somewhat heavier, and is also sold by Quest.

In earlier posts on this thread, I indicated preference for certain Gold-Tip arrow shafts to make flexible poles for dome tents, but would not recommend them for the EMP design, due to the long elevated ridge pole on your tent, which would need to be stiffer.  One of the Victory shafts, with a ‘300’ spine, is stiffer, but not quite as strong as the Gold-Tips or the heavier Easton CF.   I think there was a review of your tent on BPL, and you might be able to dig it out of the archives, but doubt it would provide pole lengths.  I ordered a Mountain Hardwear tent of similar design, but returned it because my side entry tents are as light and more spacious and stable.  The BPL review might help in deciding whether to put in the effort to make poles for your Easton tent, and deciding whether to use alloy or CF.

I still believe that in the right applications, the best quality CF is as strong, and is lighter, than the alloy, but recognize that due to poor quality of most CF tent poles in the past, people are wary of them.  As Bob Moulder’s posts on this thread indicate, the CF will make a lighter, stronger and stiffer upright pole than will alloy, and that’s using CF tubing ordered on eBay.  For applications where the poles are flexed into hoops, choice of alloy vs CF is not so easy.

[Edward John M]

Melding CF tubes with Aluminium alloy tubes works for mid poles, has there ever been a composite solution for tents with hooped frames that mixes alloy and CF?

Is there a reason it isn’t done or if done isn’t common?

 

[Roger Caffin]

It sticks in my mind that someone produced a composite pole of CF sides and a really curved Al top section. But I cannot remember who.

Of course, there is always the option to have ‘straight’ CF poles with bent metal elbows between sections. I do that with my tunnels. It works fine.

Cheers

[Sam Farrington]

The review of the EMP 2P tent was here:

https://backpackinglight.com/brooks_range_foray_tent/

Edit:  Please disregard post.  Link is to a review of a Brooks Range tent, not the EMP!  My error.

[Will Penney]

I have experimented with both the options that Roger mentions, for a hoop-shaped pole with prebends.  I used Easton Custom Carbon tubing (which I believe replaced Easton’s Carbon FX), with the same ferrule diameter as Easton 0.340″ tubing, but a slightly higher stiffness than Easton 0.355″ ‘Expedition Aluminium’ tubing.  Compared to a 6 section 0.355″ pole:

a pole with 4x Custom Carbon, and 2x prebent 0.340″ poles was 78% of the weight (22% saved)

a pole with 6x Custom Carbon tubes and 3x 20° aluminium arch connectors (elbows) was 76% of the weight (24% saved)

The first option is less expensive, and provides a pole with a continuous curve (no sharp coners).  However, due to the differing stiffness of the 0.340″ vs Custom Carbon tubes, the mixed-section pole has a different shape – rather pointed at the top.  This could be solved with 4x prebends and 2x Custom Carbon tubes, but the weight saving is then small.  The other problem is that the points of highest stress are often around the 10 o’clock and 2 o’clock positions (depending on the pole layout, guying options and other variables).  This is uncomfortably closer to the weaker 0.340″ Aluminium tubes, which I suspect will be more highly loaded by the stiffer CF tubing.

Of the two I prefered the solution with arch connectors.  I found the arch connectors, though visible, had a minimal effect on the tightness of the Silnylon fly, and the overall shape was a better approximation of the all-aluminium pole with prebends.  I suspect it is also a bit stronger.

Sam and Roger both have good information above.  I agree with Sam that in this case there is not a clear best option.

[Franco Darioli]

NM

 

[Daryl and Daryl]

 

I recently reevaluated the use of carbon fiber tubing for the myog frame pack design I’ve used for 15 years or so. .

Plus=I save about 1.5 ounces (about 10% of the backpack’s approximate 1 lb weight) by using carbon fiber instead of aluminum.

Minus=The carbon fiber tubing is more prone to breakage than the aluminum,  It can break suddenly and totally.  (It happened to my wife’s pack at the beginning of a backpacking trip to New Zealand a few years ago.  I also happened to a tent pole section many years ago.)

My wife (and many others) are not good at fixing broken items,  So for their use I’m switching to an all aluminum frame.

 

[Roger Caffin]

Hi Will

Your weight figures puzzle me slightly. You must have had very heavy elbows maybe? Certainly, my CF tent poles are significantly lighter than they would be in Al.

Anyhow, I would LOVE to see a photo of your tent. Please?

Cheers

[Author]

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