Cracked petzl darts

Kyle Tarry wrote:

Karl, this link isn’t working for me.  Can you post a photo?

Here is a snapshot from the video.  The same horizontal ”beam” cracked.  Looks like the climber was using them with dual front points.  It appears that the location of the cracks are on the outside contact points of the dual front points, where the highest shear stresses would be expected.  So, a similar but slightly different case from the Dart failure in the OP of this thread.

After breaking my 3rd (and last) pair of darts I’d thought I’d revive this thread.

Since I first posted this on here I’ve broken 2 more sets of darts, averaging a 2 season lifespan per set. When I broke my first set petzl said it’s because the bolt wasn’t tight enough and cause the bar to crack, however on my last 2 sets I’ve always kept the bolt tight and they still break.

I know of this happening to several people locally, so I thought I’d just check in to see how many other people are breaking darts.

Kevin Mcbride wrote:

After breaking my 3rd (and last) pair of darts I’d thought I’d revive this thread.

Since I first posted this on here I’ve broken 2 more sets of darts, averaging a 2 season lifespan per set. When I broke my first set petzl said it’s because the bolt wasn’t tight enough and cause the bar to crack, however on my last 2 sets I’ve always kept the bolt tight and they still break.

I know of this happening to several people locally, so I thought I’d just check in to see how many other people are breaking darts.

What did you replace ’em with? 

Dang that crazy. Good find. I am going to check for that as well. Hopefully petzl will replace that for you. 

There are a few known failure modes on petzl modular crampons (lynx and dart). Toe bails snapping is the most common but I’ve heard of this. Make sure you tighten all screws every time you go out and dry your gear after your trips. Other brands overbuild this component better than petzl. 

Nicholas Budka wrote:

There are a few known failure modes on petzl modular crampons (lynx and dart). Toe bails snapping is the most common but I’ve heard of this. Make sure you tighten all screws every time you go out and dry your gear after your trips. Other brands overbuild this component better than petzl. 

It’s definitely not just from the bolt being loose, that’s petzls excuse when in reality the darts are just built like shit. This is coming from someone who has broken three pairs. Just buy different crampons.

Kevin, what’s your go2 Dart replacement now a days? 

Nat Shultz wrote:

Kevin, what’s your go2 Dart replacement now a days? 

Blue ice makes good technical crampons now

Did a short analysis of this issue for an engineering project. It's not super detailed, but I thought it was pretty cool. The cross-sectional area of the crossbar is surprisingly small, and it's asking a lot to support that much force. If you are a heavy climber, the bar could fail from cyclic fatigue with a fairly low number of cycles. PM if you want the full report. 

If anybody has some of these broken crampons laying around, I'll buy them for cheap! I have ideas.