19 November, 2011

Petzl Myo XP repair

My first headlight was the Petzl Myo XP and I loved it from the beginning. Very well designed and build with little things to pick on.

I was pretty amazed when after 1 year of use my headlight broke down experiencing cable problems on the side where the cable enters the light head. Didn't thought much about it and put it all on a bad production sample, just returned the product to the store and got a brand new one instead. I've got mine from a local supplier, Himalaya, having luck on my side as there guys are big and serious about their business with all interests in keeping a good name about the products they promote.

All was back and track again till 1 year after when this 2nd headlamp failed with same symptoms. This time I was more than intrigued and determined to get tot he bottom of it my own way.

There's nothing you can't do with the right tools so in no time it was all pieces on my worktable. As I was anticipating, the good design from the outside was found inside as well. The LED chip is mounted on a separate PCB that has an extra aluminum radiator for efficient heat dissipation. Even more, a thermal probe is mounted on the heat-sink for thermal shutdown protection.
The LED chip looks like a Cree product but I might be mistaken. All looked fine with the solder points so with a multimeter found my problem to be inside the cable. Only solution now was stripping it apart little by little.

Need I say my surprise when finding the inner conductors? I couldn't believe my eyes, finding the wires in such a bad shape in such a high overall quality product. It looks like the wires suffered severe aging problems from low temperature exposures, at least that's the only thing that makes sense to me. They isolation layer lost it's elastic properties and cracked all around in multiple places. One of them got more mechanical stress than the others and that's how the electrical link failed.

The only thing I could do in this case was to cut away the most exposed part of the cable and resolder it to the PCB. Of course it got shorter in the process, of course I didn't solve the problem, just the effect but for now it will have to do.

UPDATE: Another Petzl Myo XP repair

CoolLCD Super Clamp tweak

With my CoolLCD order I got 3 Super Clamps, little widgets that are priceless bargains for any photographer out there.

If there's not much I can say bad about the actual clamps, the included extender with 1/4" and 3/8" thread on the other hand is pretty poor design.

First, it lacks any rubber washer on the base of the threads. Second, it doesn't offer any firm grip area when you want to tighten or loosen the screw. And last, I tend to think the material is on the soft side as I noticed with one of the extenders that the 1/4" thread got bended.

At least I got rid of the first two problems with home made washers from a rubber carpet and a little lathe work to get that needed grip area.

I included a before and after picture (without the washers though).