Be sure to check the tailcap. My money would be on the retaining ring for the switch being loose and not grounding properly. It would explain the flickering then complete failure. Make sure the retaining ring in the switch is tight before you do anything else with the light.
A quick way to test is to remove the tailcap and, with the batteries in place, touch one end of a paperclip to the battery negative and press it against the batteries while touching the other end of the paperclip to the unanodized part of the battery tube. This will bypass the switch and tailcap. If the light fires up then the problem is not the driver and is in the switch. If it still doesn't light up then check the ground on the driver itself.
If the driver is held in with a threaded retaining ring make sure it's tightened fully as well.
Sounds like a short somewhere. I doubt the light would draw enough to trip protection on 4x26650s. That is a lot of juice.
Id expect a spark at that voltage and any current above an Amp. But with no light coming out, I suspect a short somewhere.
Should have said - I have checked each battery in a T6 zoom torch and all worked fine.
Also re-charged all (as I’d initially hoped it was just a case of being dead batteries.)
When you say it wasn’t a great idea to do what I did with Li-Ion - to confirm, I shorted out at the tail cap end, as the switch would do. Did you think I shorted out at the LED end?
As above - already done the ‘paperclip’ thing and no light.
Connections on the switch and driver both look good.
Got a cheap multimeter ordered - can’t hurt to have a spare and I did have £3.08 needed in my paypal account, but didn’t have any time to look properly today.
Also, noted that when shorting at the tail cap end that there was enough current to create a magnetic field that tugged on the top most battery a little.
When I do have access to a multimeter, what should I be looking for?
Will check power is getting to PCB, then getting out of PCB, but presuming it is getting to but not out of, what should I be looking for?
If I stick my multimeter (set to ohms) across the larger capacitor, it shows a negative value which changes, though seems to be going down (a quick google suggests it should be going up?)
The smaller capacitor shows 0 and no change - could this be the problem?
Need to work something out to be able to test for voltage with it all plugged in - no crocodile clips etc.
The LEDs in the head might all be wired in some type of series-parallel configuration or they might all be in series. It’s possible the wire came off one of the LEDs in the head and the driver can’t power any of them any more.
I’ve had several lights that got hot enough to have a lead slip off due to a bad solder joint. You might want to make sure all the wires are still hooked up to all of the LEDs.
From what I can tell the LEDs are in two lots of six.
All still soldered correctly. Checked and there’s no voltage at either of the positives that connect to the LEDs.
Any ideas how to check the other components on the board?
I really wouldn’t want to put four unprotected cells in series tbh, have you tried it with the reflector off? There’s definitely a short somewhere to get a flash when you linked out the tailcap, so its a case of tracking that short down. reflector is a distinct possibility.
Especially on something that might have a short, I suspect!
Kaidomain sent an email saying their payment system was working again.
I’ve found a UK supplier of another one and because I’m foolish, bought that (I’m a tad broke at the moment, this may be why!) - I did have plans to use these with a diffuser for ebay pictures in my unit with no power, so would need two anyway (I keep telling myself ).
So will probably just send cap and head back as requested.
Back on this.
Unfortunately was very busy time at the time, so it never got sent back.
Think I’ll just try and fix it up and get the mods described in the review thread done at the same time.
I’ve now got a better multimeter (not amazing, just a Vichy VC99).
This does show the larger capacitor as about correct, but the smaller one as not working.
I don’t know if it’s happened since, but the larger capacitor has actually had one leg come off the circuit board - possible it was just that.
Am I the only one that sees the driver is completely blown out and burned where the caps & toriod are soldered to the board? See the big black craters? I know this is an old post but you need a new driver lol.
I think that’s just the solder blobs that look a bit dark because of shadowy lighting and lots of flux residue. The only possible problem I see is the negative (upper) lead of the right most capacitor looks like it is not soldered properly to the board.
Yea- you’re spot on with that.
Since found that’s the case with the loose one, but hadn’t noticed when I took the picture - though the smaller capacitor doesn’t seem to be working properly too.
Unfortunately a) I’m not that great with fiddly soldering and b) not sure where my soldering stuff is.
I did try doing reattaching by heating up a screw and using that, but not surprisingly, that didn’t work (almost did).
Caretaker bloke at my work units offered to lend me his soldering iron - the tip of which was a ground cold chisel with a 5mm square flat end or so!
Got a couple of other things that could do with somework, so might see if I can find someone local that can do it for a not-silly amount.
(Anyone in West Yorks, UK fancy earning some beer money? )
Maybe you can buy/order a small butan soldering lighter. I was once on holiday and needed to solder something, so I bought one. It is a jet flame lighter, you can screw a metal soldering tip on.
Heats up quickly and has a fine tip…was cheap too
I’ve got a bit knackered one of those SOMEWHERE too.
I’ve got basically most of my life haphazardly thrown in the back of my business unit and haven’t had chance to organise it.
Bit broke and so prefer not to spend money on stuff I’ve already got.
That and my fine soldering is far from amazing - I fear I’ll end up with a driver-sized mush of solder if I try!
Don’t go with Butane its a real pita. Mine will lose its butane charge every few weeks then I have to refill it every time I need it. For the small stuff I use an electric 12 watt Weller soldering iron/pencil.
).