Jeff,Right...the head is not "wobbly"...the o-rings make it feel nice and tight.
But...the electrical contact of the threads is variable. Isn't that just how machine threads work? They need some clearance so they can turn.
To see for yourself, try these two simple tests:
Test 1: Unscrew the head 1/4 turn. Turn the light on and click to High mode. Grab the head and tail, and gently pull them apart or push them together. Does the light flicker? If not, unscrew the head a tiny bit more and try again. It's luck of the draw, but I bet it only takes 1 or 2 tries before you see it flicker on High.
Test 2: Unscrew the head just past the o-ring. Or if you prefer, remove the oring and screw the head back on most of the way. Push/pull on the head. With the o-ring out of the way, can you feel the tiny movement of the threads?
FYI, I have two new Quark heads, nice and clean. The tactical one has a light application of triflow on the threads and o-ring, because I expected to rotate it a bunch of times to program it. The regular one was cleaned with a cotton swab but not yet lubed...it has only been loosened and tighted about a dozen times so far. :thumbsup:
Am I off base here? Does anyone see this flicker when they push/pull on the head?
It's not a big deal...I plan to just use the bezel-tightened modes...but I am curious if others see the same issue with this design.
I unscrewed the head over a full turn and there was no play, no flicker, just steady constant light, solid as a rock. I think maybe the triflow is not the right lube to use on your light.
I'm using a light silicone grease on both the o-ring and the threads. Before I applied the grease, I cleaned all of the oxidation off the threads until they were shiny silver, then applied the grease, and everything is smooth and silky.
The light is solid with never even a hint of flicker. If I unscrew the head past the o-ring so that it is hanging on by only a thread, then yeah, it feels loose because it is at that point.