Trekking pole physics question: how do the # of sections effect durability?

[Hanz B]

So I have an obscure question.  Recently I broke a Fizan trekking pole navigating over a large Fallen tree. I think I simply bent it against the trunk, but under the right conditions it just collapsed and broke in half right ontop of the press fit fastener. Massdrop is about to offer them again and since I like them so much  i’ll go ahead and buy them again.  They offer a 3 component and 4 component version.  Got me thinking, which would be least likely to break in the future assuming similar use.  Trouble is I don’t know exactly how the diameters are different but assuming most things equal between the two versions one would have there points of overlap the the other would have two. One may have either a smaller diameter for one section of the pole or a langer diameter, but this is unknown.

Anyone want to venture an educated guess on which would likely be more durable? And if comfortable, venture as to how it would compare to two section and non sectioned poles?

Fyi the version I broke was the 3 component version.

 

 

[Matthew / BPL]

Too many unknowns. Maybe email or call the manufacturer?

[Lester Moore]

Educated guesses away… if each section fastener is a weak link, then the more fasteners, the more weak links. Therefore, the fewer sections, the stronger the pole (all other things being equal). Fewer sections will also decrease weight and decrease the potential for malfunctions (fewer parts to go bad). Of course, pole thickness and diameter may not be equal between models with different numbers of sections. And there are other points of failure on poles that may be more likely to be a problem in the field (tips snapping, rodents chewing the leashes, etc).

However, having at least two sections allows you to adjust the pole length (an important feature IMHO). But two sections is still a bit long and unwieldy when collapsed. 3 sections gives you a reasonably compact package when collapsed (good for affixing to a small pack or inside carry on bags) for the tradeoffs of double the potential fastener failure points and slightly more weight.

Four sections seems a bit to much of a trade off in failure points, fiddle factor and weight IMHO, unless you really need a very short and compact package when collapsed. BTW, I love my Fizan trekking poles and will probably buy a backup pair when available on Massdrop.

[Ben H.]

Anyone want to venture an educated guess on which would likely be more durable?

Sure…. 4 sections have more failure modes than three sections, so more likely to fail.  In reality one joint (I’m guessing the smallest) dominates the likelihood of failure and so which ever pole has the weakest joint will be the most likely to fail.  Again I would guess the 4-section pole would have the weakest link (smallest joint).

On the flip side if most people get failures mid-section, then the longest section between joints would be the most likely to fail.  that would argue towards the 3-section pole.  Since you experienced a failure at the joint this seems less likely.

 

 

[Franco Darioli]

I assume you are talking about the Compact series.

The 3 sections are poles are 17/16/14 mm, the 4 sections are 17/16/14 and 12 mm.

Therefore the 4 section would be more fragile.

[Bob Moulder]

Under the right (hmm… wrong) conditions you can break any of them.

But I agree with the logic of 3 being a tad better than 4.

While I prefer my very light, 2-section MYOG carbon fiber poles, I would not recommend them to  “tundra thrasher ouch man 2”  :^)

[Hanz B]

So looked back at my breakpoint. It was right above the pressure fit locking mechanism on the two larger diameter poles – only the top one failed – and it kind of ripped off leaving the mechanism exposed. so my thoughts after listening to you all is 1) reduce the number of failure points 2) but many other factors play in, obviously mine did not break at the smaller diameter tube, so my leverage was likely placing a moment arm on the top half of the trekking pole. So I will go with the three’s again.

perhaps there is a third lesson here. I do think I noticed the slightest bit of expansion in the aluminum around the pressure fits at the uppers. so maybe I was tightening them too much…it Is interesting to wonder if dealing with a little bit of slip now and again could actually help avoid the types of inevitable torque during a lone hike. It almost makes sense that if you apply enough force and the pole collapses instead of bending around the mechanism than you save the pole, but alas this could be Saftey conscern if not appropriately managed.

So perhaps the third lesson here is do not overly tighten and instead expect an acceptable level of designed failure in the locking mechanism to save the pole from stresses likely to break it. What do you guys think?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

the

[Ben H.]

So perhaps the third lesson here is do not overly tighten and instead expect an acceptable level of designed failure in the locking mechanism to save the pole from stresses likely to break it. What do you guys think?

I would agree.  I’ve noticed that novice engineering tends to try to prevent movement and make things stiffer, while good engineering designs for the expected amount of slippage.movement.

 

 

[Lester Moore]

good engineering designs for the expected amount of slippage.movement

Make a lot of sense. So a pole that is inherently more flexible, like bamboo Soul Poles, may be less likely to break under stress:

[Hanz B]

If didn’t need to fly with my poles I would buy those bamboo bad boys right now! Wow.

[Lester Moore]

Bamboo seems like a good option for folks who do a lot of bushwhacking and don’t need adjustable poles. But at around 9 ounces, they are not the lightest option, but no worse than tradition pole weights.

[Author]

Posts