I've been really impressed with the new AA Fenix lights but the threads on the head were dissapointing. Out of the box the head is ok to turn with 2 hands but difficult to turn with one. This is what I did to make it better:
1. Grease and clean the threads
This would probably be easier with a thread cleaning tool (thread chaser?) but I didn't have one so I improvised. First remove the o-ring and take out the battery. Then slap some grease on the threads and spend a few minutes turning the head on and off. After that wipe out the grease with a towel, and repeat until all the grit and funk is out of the threads. Grease the o-ring a little and reinstall.
2. Add o-rings to the head
I put the spare o-rings that came with the light in the two shallow grooves on the outside of the head and another o-ring in the thicker groove on the head.
Now with the cleaned up threads and extra grip of the o-rings the head should turn easily with one hand.
3. Fixing the donut and candle/flood mode
Take the head off the body and use some rubber bands to unscrew the two halves of the head. Clean out the chunks of loctite and screw the head back together.
Now you should be able to turn the reflector with 2 hands and a little effort, but it should be tight enough that the reflector won't unscrew under normal operation.
Turn the light on and unscrew the reflector just a little bit until your donut goes away. At this point you can also easily remove the reflector if you want and you'll have a light with a huge flood and no hotspot.
1. Grease and clean the threads
This would probably be easier with a thread cleaning tool (thread chaser?) but I didn't have one so I improvised. First remove the o-ring and take out the battery. Then slap some grease on the threads and spend a few minutes turning the head on and off. After that wipe out the grease with a towel, and repeat until all the grit and funk is out of the threads. Grease the o-ring a little and reinstall.
2. Add o-rings to the head
I put the spare o-rings that came with the light in the two shallow grooves on the outside of the head and another o-ring in the thicker groove on the head.
Now with the cleaned up threads and extra grip of the o-rings the head should turn easily with one hand.
3. Fixing the donut and candle/flood mode
Take the head off the body and use some rubber bands to unscrew the two halves of the head. Clean out the chunks of loctite and screw the head back together.
Now you should be able to turn the reflector with 2 hands and a little effort, but it should be tight enough that the reflector won't unscrew under normal operation.
Turn the light on and unscrew the reflector just a little bit until your donut goes away. At this point you can also easily remove the reflector if you want and you'll have a light with a huge flood and no hotspot.