I have a light displaying a weird problem and I cannot find any threads that seem to match. I've been through the all of the steps outlined on several troubleshooting threads.
The light is a Balder SE-1 XM-L that takes AA or 14500 cells. It worked fine for several months but has now taken to cutting out as the tailcap is tightened.
Often, if I drop a battery in and tighten the tailcap, the light won't turn on at all in any mode. Loosening the tailcap may sometimes cause it to flicker into life but often it requires complete removal and replacing of the tailcap again. I put the cap on a couple of turns and the light comes on, but as I tighten it, the light dims, flickers and then cuts out completely.
I have tried all of the troubleshooting tips I could find. For instance:
Tested with multiple different cells.
Cleaned the threads at the tailcap. (The balder head is non-removable as far as I can tell)
Disassembled the tailcap and reassembled, checking everything is tight. (The tailcap on the balder has a plastic retaining ring and thus all the electrical contact is done through the threads.)
Swapped tailcaps with a known working one from another Balder SE-1.
I've tried using a multimeter to take tailcap current readings using the 10A scale. I get erratic readings and unreliable mode switching which is dependent on how much pressure I put on the meter lead.
The fault seems to happen whether I'm using my Keepower protected 14500s or regular Eneloops.
My guess is that something on the inside of the driver board is faulty and that pressure is causing it to lose contact. I can't see a way to get into the head but looking down the tube, there is a "reverse polarity" ring around the positive contact. There is no spring in the head, just a flat contact on the board. I've used a chopstick to "prod" this area, but I can't seem to detect any play or deformation and nothing seems loose.
I have mostly been running protected 14500s in it. They are a little longer than my Eneloops but I'm not in the habit of screwing up the cap extremely tight. I wonder if the pressure caused by the additional length of these cells has gradually had a detrimental effect?
It would still be under warranty but the cost of shipping it back to Intl-Outdoor from Australia would be more than the light is worth.
So..... I'm throwing this to all of the brains trusts out there. What do you think might be wrong? Has anyone else ever had a flashlight that behaved this way and how did you fix it?
I'm not entirely averse to replacing the driver/pill if I can find a way to get into it but it looks to be designed not to come apart. If anyone has disassembled a Balder SE-1, any tips would be most welcome.
Seems no-one has been able to offer an opinion. In which case I won't bother at this time with photographs - PM if you want a more detailed explanation.
Just to close the thread in case this happens to any other SE-1 owners.....
After a bit more reading in here I discovered that the pill can be unscrewed from the body. I used a length of rubber bike tube to grip it.
Testing the pill manually by holding the negative lead against the threads gave no light at all which I thought strange. It was then I realised that since the pill is not ferrous, the driver is simply pressed in and not soldered to make proper contact. This leaves all of the electrical contact to take place between a small lip on the outer surface of the driver board and the inner lip of a "ledge" the body itself.
ie. The threads of the pill make no electrical contact at all!
I suspect what has happened is that the driver has been gradually pushed back into the pill (it wouldn't have to be much - the proverbial bee's dick) and the pressure of the battery & tailcap pushes the contact ring just off the internal body lip. Hence, flicker and then - no light!
For the time being I have made a "washer" from length of solder, hammering it flat and working it into the body. I then screwed the pill back down on top of that. So far, it seems to be working, though the O-ring is not quite down below the upper rim of the body tube - but close enough. With the head screwed back down there is no visible gap.
I did think to place a couple of small dobs of solder onto the contact ring, but went with the "washer" idea in case an air gap added to any thermal problems. Don't know if it makes any real difference but.......
So I'm happy again. On two eneloops it is impressive but on a 14500 it simply rocks!
I had a similar problem with my BC40. I found out it was one of my protected cells. As I tightened the tail cap it squashed and I presume shorted the PCB on the cell. They were Trustfires by the way.
