Fireflies ROT66 Flashlight

Thanks for your input. This isn’t the sort of light that I would use for camping or other important roles so I’m not overly concerned about its reliability, but I’ll definitely be keeping an eye on it and not leaving batteries in it long term.

Using an aluminum spacer may create a new path for the negative to flow through the battery tube and tail cap. That should be okay, but you might not be able to lock out the light. I would recommend using either a paper or plastic spacer.

You should be able to manually lock it out by twisting the battery tube or tail cap. I do this with all my e-switch lights. There’s no chance of it accidentally turning on as well as no power drain at all.

Ok, will try a plastic one then and see how it goes thank you.

Ish. The ROT66 doesn’t use the body tube to conduct electricity, so locking it by loosening it isn’t guaranteed to work. It can run even with the tube and tailcap removed.

That’s odd. On the two I’ve tried, it doesn’t matter which direction the tube is. I just make sure to tighten the tailcap onto the tube, then tighten the tube into the head, and it keeps the battery carrier pressed against the driver with as much force as possible. I also think it looks a little nicer that way — with the slack area between the tube and head, where it’s invisible, instead of between the tube and the tail.

I don't understand it either. Sometimes things don't make any sense until they do, this could be one of them.

In the case of the MF lights, and I assumed this one, loosening the tail cap or battery tube should allow the driver spring to push the carrier away from the head breaking the negative contact.

This doesn’t work on the ROT66? How can the light possibly run without something pushing on the carrier to compress the driver springs?

In one of my ROT66’s the battery carrier is so tight that I can push it all the way in and run the light with no tail cap at all - of course you can bump it and disconnect

/\ Set it lens down & the carrier will contact the spring. That would do it wouldn’t it??

The carrier has to touch in 2 points to get both positive and negative electricity flowing. The driver spring is the positive and the carrier has to touch the body around the driver area.

As long as something is pushing the carrier all the way down allowing it to make contact with the head in 2 places, you will get power flowing.

The bump issue could be caused either by the carrier compressing against the tailcap and losing contact at the head or it could be from all three batteries compressing against their springs and losing contact at the positive end.

Does the tail cap press directly against the carrier or does it have something spongy between them?

:person_facepalming: …… Yep, I overlooked that minor detail it seems. . :person_facepalming:

Oh well…… back to the drawing board. . :smiley:

So I got the light back that I had the auxiliary board put in and placed batteries in it charged to 4.19v. I returned from work 3 hours later and the red LEDs had kicked in. They were now at 3v each. I charged them overnight back to 4.19v and turned the light onto the moonlight setting at 5 this morning, took my wife to the hospital for tests, took her to breakfast back to the hospital then home almost exactly 4 hours later and tested the batteries. They’re at 4.1v

So your aux LED are drawing more than moonlight. I’ve had my aux LEDs on for four or five days and my battery charge hasn’t moved. All three at 4.19V just where I had them. My aux LED came preinstalled.

PS that’s a short workday :thumbs up:

No, it’s more likely it was some type of other drain.

FF,
When might your PL47 be in stock? I’m interested in a 3-5k lumen headlamp that might fit my current headband.

That’s extremely high drain… like 3 Amps. It sounds a lot like one of the batteries might be inserted backward.

It couldn’t be a backwards battery because that would cause a direct short and the springs would melt and you’d get smoke as you inserted the battery.

I don’t think so. The light uses dual gold plated BeCu C17500 springs. It’d be almost impossible to melt them even in a direct short.

I do wonder what caused the large drain inside of the ROT66 though. Is it possible the light got activated by mistake inside of a bag or something, and drained down to LVP?

I’m repeating the experiment with 2 completely different sets of three batteries in the two lights. I think the third one arrives Monday