Mashing the LED PCB into place didn’t entirely solve the weak beam problem, so I unscrewed the tailcap holding the switch on the other end of the body:
Unscrewing the lock ring releases the switch assembly:
I suspect the tab sticking out from the side of the switch doesn’t make / never made good contact with the aluminum tailcap body, but having gone this far there’s no reason to stop. The plastic housing around the spring-loaded brass battery contact pops off to reveal the actual switch:
The long tab on the front of the switch sits under the spring, so that’s the negative battery contact. The LED current goes through:
- battery negative to contact + spring
- switch tab + moving contact + tab
- tab to tailcap pressure fit
- tailcap threads
- front tube threads
- LED pill to PCB
- spring to battery positive
So. Many. Aluminum. Joints.
The switch body snaps apart to disgorge a remarkable number of parts:
Nothing looked out of order, so I applied a thin layer of DeoxIT Red to all the contacting parts and reassembled everything.
For the record, the switch’s internal parts have many plausible assembly sequences; the workable one goes a little something like this:
Contrary to what you (well, I) might think, the switch is off when the central contact is pushed forward, away from the side contacts.
I bent a slight angle into the tailcap contact (on the right in the picture) to make better / firmer contact with the tailcap body, cleaned all the threads with a cotton swab carrying a dab of DeoxIT, and screwed it all together.
With everything back together, the beam seems bright and steady again. We’ll see how long it lasts.
The Smell of Molten Projects in the Morning 