Wednesday, May 14, 2008

Session 8056-58: StokeLAB Leash Snap and Failure Analysis

Day 56, 57: Leash Snap and Failure StokeLAB Analysis

This morning, I went in the water, paddled out and tried to catch a shoulder level wave. I paddled into the wave and the wave closed out on me, and I got off the board. Next thing the normal tugging feeling of the board was gone. I had this bad feeling another time, and sure enough the board and myself got separated. I must say though this time, I was further out and I had to swim for a bit to get to the board.

Photo 1

Photo 1 shows that this time the leash did not snap nor broke from the joint. Previously I have known several people where the leash did become disjointed from the ball-joint and came apart. In my case it was the plastic base where the leash connected to the base of the ball joint assembly. Photo 2 shows how the leash and the cuff came apart. Again, note that the leash came out from the cuff and not from the joint. The root cause of the failure was the fatigue in the plastic base that was woven into the cuff.

Photo 2

Photo 3 below shows how cleanly it broke off from the base of the cuff. The plastic ripped right out.

Photo 3

The root cause of this is the plastic stress and fatigue. I actually should have replaced this leash at least 6 months ago because I have been using it for more than a year, which meant that it has gone through at least 100 sessions or more.

Everyone, be careful, and do replace your leash at least once a year!

Day 57 THU: After yesterday's mishap, I got a got an FCS leash which is not the same brand that broke. This morning was strangely warm, and offshore winds and no crowd but a lot of backwash that made it very difficult to ride even I caught waves (M)

Day 58 FRI: Owning the whole beach by myself and had some really fun long waves with the building W swells. I've added baby side-fins on my 7'2 Egg. (D)

Day 59 SAT: The same spot gotten closed out with more direct hit of the W swells. Should have gone to "R." (D)

No comments: