Solarforce Switch problems - erratic when screwed down

I rely heavily on Solarforce P60 hosts, particularly the L2P. The first one I bought 15 months ago is solid and trouble free.

I recently bought another complete L2P host, plus 2 additional/spare reverse click tailstand caps, for a total of 4 reverse click tailcaps owned.

On all 3 of my new tailcaps, the light will erratically cut out when the tailcap is screwed all the way in, if I unscrew the tailcap to relieve some pressure, the switch then works fine…no dimming, no dropouts. Its as if too much tension on the spring is causing some sort of odd behavior and shorting with the switch. Help! What’s going on?

Batteries are 18650s, either Orbtronic 3100, or Panasonic NCR18650B.

If you look inside the tailcap, you should see a threaded aluminum retaining ring that holds the switch in place. Try tightening the retaining ring with a sturdy pair of tweezers or some circlip pliers and see if that helps.

Check the retaining ring inside the tail cap—could be loose and when you dog down the tail cap it’s pushing the switch away from the retaining ring—Snap ring pliers work best but needle nose pliers work to
Wow we must of been replying at close to the same time with same answer

I check those right off the bat on all my lights, a loose retaining ring is not the issue in this case.

What kind of dropin are you using.

Edit: try taking apart the tailcap assembly (clicky boot etc) and see if there’s a bad connection somewhere. Missing solder or solder breaks. Maybe the rubber boot has too big of a nub on the inside causing it to “half click”

I have 3 drop ins that I’ve rotated and experimented with. 2 came from International Outdoor Store. First is XM-L2 T6 3C which is wonderful as far as brightness and tint, second is XP-L U5 7A3 which I hate…its far too yellow, and dim. The third drop in is a single mode Cree XP-G R5 from Solarforce, and its not too bad for a lower drain, less floody, general utility role…but the tint is still a bit on the blue side for my tastes.

Maybe the problems at the other end. Bad driver ground or reflector shorts to emitter pos when under pressure.

I’ve had the same issue. In my case it was the drop-in spring. It wasn’t making proper contact. A bit of sandpaper action and all is fine. :slight_smile:

I’ve had a rash of bad luck with switches themselves recently, all due to the nub on the boot being slightly to tall (I’ve also been replacing all my SW boot’s so it’s a parts incompatibility issue) holding the plunger just ever so slightly depressed. When that happens I just cut about 1mm off the nub and all’s well again.

You may also want to consider replacing the switches with a Mc Clicky switch. THey seem to have a better feel, and are a little more reliable. Or even a Tofty 10A switch.

My two cents:

(Just re: my P60s) Just about every tailcap I own has a different stack of goodies inside, even though most of the switches-on-boards are ~similar. I have to be very careful to keep the things like the plastic lump that fits around the switch body, the customary washer(s) (metal and plastic), etc. together with the tailcap they came in. Rubber boots aren’t even fully identical, as some have the lump over the switch button, some don’t.

Here’s what I think is happening: When you tighten the tailcap’s retaining ring, you’re actually tightening against some of the stuff between the switch board and the rubber boot. Then when you tighten the tailcap, the end of the Body mashes on the retaining ring, before it’s all the way screwed down. At that point, all is well electro-mechanically, but when you crank it down either the retaining ring, the circuit board or the “stuffing” above/around the switch get distorted somehow. Possibly the friction between the body and the retaining ring is enough to get a little more ‘turn’ in the ring, which would cause erratic behavior.

You can always assemble one without the rubber boot in place, the better to examine the “nether regions” of the tailcap in situ. It may even be that you’ll need to remove “packing” to get the switch’s circuit board “deeper” in the tailcap…

With the switch ring snugged down all the stack height issues should be eliminated. Either it works or it doesn’t. Loosening the tail cap should not affect the button or any of the tail cap stack. With all 3 switches behaving the same it points a connection issue at the other end, ground spring, solder ground, or the very common reflector short. If the springs aren’t getting weak from over heating due to a short I would look to the ground possibilities. That or you aren’t snugging the retainer all the way and tightening the tail cap does in fact mess with switch stack as the others have said.

Excellent point Scott! Maybe even try wrapping the drop in with some copper tape or aluminum foil to see if it solves the issue.

Did you resolve this problem? How? Didyou try using the end cap from the other Solarforce to see if you had the same problem or if the problem disappeared?