Portland wrote:bretonbikes wrote:Looking at the construction of such poles most appear to come from the same few Chinese factories - you will see that the thin ferrule is held in place by being pushed into the pole section and then four small dimples being bashed into it to grip. Often with new poles you'll see tiny cracks here, and with time those cracks will open so it's worth keeping an eye on them to predict when they are about to go. This is where most failures occur. By definition then the worst poles will be those with lots of joints in order to make a shorter pole - try to avoid such designs. Some poles (like DAC) are now an interference fit rather than dimples and they do seem to last better.
As I say I'm hopeful of the retailer and Vango sorting this, but on the design issues you mention, I have no idea what DAC poles are. A manufacturer?
I was wondering if short section poles may be an issue as I noticed that the new 55cm sections of pole which Vango sent me seemed to flex rather more than the shorter sections used on the tent - the 55cm length of course was cut down to the appropriate length and as I may have noted elsewhere the lengths are not all the same. I rather had the impression that the shorter lengths didn't flex as much and instead transmitted more force to the join between the ferrule and the "outer" of the next pole. In both cases it was this "outer" which broke. The ferrules lived merrily on.
I don't have all of the tent poles in front of me at the moment but yes I did note that many seemed to have the ferrules fastened to the rest of the pole by the "dimples" method. This might be something to do with the fact that the pole metal is colour coded but the ferrule is bog standard silver.
The replacement 55cm sections are completely silver and there are no dimples that I can see where the ferrule joins the rest of the pole - maybe they are interference fit.
I should stress though that I inspected all the poles for damage, saw no cracks or anything, and no ferrules have failed.
The problem is that at the joints the alloy is actually twice the thickness (i.e. the ferrul and the pole combined) so that section will be very resistant to bending so yes a pole with many joints will be much less flexible, and at each joint the thinner pole section will be stressed where it meets the stiff joint rather like bending a stick over your knee.
Looks like the replacements are better - DAC are a pole manufacturer.
As an aside, our season has just finished, and the aforementioned Robens tents http://www.robens.de/en/Products/Tents/ ... odge2.aspx are the first we've ever had to complete a season without a single pole breakage and have been hugely popular with our clients. Can't tell you what a relief it is to be able to give out totally reliable gear!