Magnetic cap for Sofirn D25l headlamp?

LED Flashlights – General Info 18650 Flashlights
1

I’ve got a D25L headlamp and thought a magnetic cap would be really handy for it, the only problem being they don’t list one to fit?

Does anyone know if the below cap would fit:

2

That won’t fit, the threading is different. You’re better off buying one of those thin disc magnets and supergluing it the inside (or the outside, if you like) of your tailcap.

3

Okay, thanks. I wasn’t sure.

Adding the magnet myself was going to be the next option. Guess I’ll look and see what size is required and go from there.

4

Hmmm… I don’t think that’s going to be feasible either. Adding just a 1mm thick spacer into the cap (under the negative spring) results in the cap not screwing on enough to seal.

The body of the flashlight would need to be reduced by the thickness of the inserted magnet in order for the cap to seat properly… Or use a much smaller diameter 1mm thick (spring wire diameter) magnet with the stock spring modified to allow it to sit under the centre of the spring…… Or, a new design spring would be required (smaller diameter) and you’d need to rely on the new spring making the negative contact through the magnet to the body…. Or fix an external magnet onto the cap- I actually have one the correct diameter sitting here.

I just checked how the SP10 Pro magnetic cap is done and it’s physically longer to allow for the thickness of the magnet.

5

Yeah, I anticipated as much. You probably want epoxy for more shear strength. Depending on how heavy your use, superglue likely won’t cut it for a battery stuck to the tail itself.

6

The external magnet won out. Anything else I could think of was going to compromise some aspect- like limit max battery length. I’ve attached it using double sided automotive tape and will give it some time to “stick” permanently before testing it. It’s quite a strong magnet so hopefully the tape holds.

The magnet diameter is 24.5mm (x 1.5mm thick) if anyone else is looking to do something similar. It’s exactly the right diameter. I think I got them off Banggood many years ago.

7

These two tailcaps are not interchangeable.

8

Thanks.