Hi,
I just got into flashlights and have been buying alot of flashlights lately.
One of my new flashlights is an Emisar D4SV2 with magnetic cap. However this spring came off it when i was screwing it back on (prob due to the battery getting drawn to the magnetic tailcap).
How do i fix this? Just glue? Solder it with some lead?
What is the material used originally to hold the spring?
/Marcus
Welcome to BLF :BEER:
I am no familiar with this specific brand/model but since the spring is part of the electronic circuit - it needs to be connected using a conductive material ie solder and not glue ...
If you just recently bought it, it is probably covered by warranty, try contacting the seller before fixing it by yourself.
Are you sure the PCB is still glued into the tailcap and only the spring came off? Or you have the PCB with the spring still attached to it in your hand, that is quite a big difference.
This is from intl-outdoor, not sure if you can see but there seem to be some dark grey stuff holding the spring.
The “dark grey stuff” is solder.
Ive been soldering alot of FPV drone boards, this looks like something ive never soldered before. Its dark grey, not shining like normal lead.
Can i use regular 60/40 lead and carefully heat up bottom of the sprint/plate and add a tiny bit of solder? Or should i solder more than just a dot?
It’s solder, basically bonds the spring to the copper on the PCB, the pictures make it look “dark grey” due to the angle.
You can solder that back with 60/40 no problem.
Probably the spring fell off due to either using too little solder paste or the soldering resulted in a cold joint (which is a matter of time until if will fall off due to mechanical stress of swring a tailcap on and off.
I do not think warming the PCB from the bottom is a good idea, could delaminate the layers of the PCB. Make sure you don’t use lost of solder wire either as that could raise the spring height and cause the space to be too tight with the cell and then the tailcap will not screw enough to have the flashlight start.
Probably you should request a new PCB with a spring, it’s not your fault it fell off.
Considering how freaking strong the magnet is im surprised the spring isnt connected using a stronger way. The magnet “sucks up” the battery every time im going to screw back the tailcap, probably going to be unscrewing the head instead going forward.
I have also sent Hank an email to get his comment about this issue and what the best way to fix this is.
I managed to solder it back together, and the light works!
FYI Hank replied to my email really quickly and let me know he had my back if something didnt work after the fix. Great customer support!
Awesome! Glad you were able to fix it yourself. It is reassuring to know that Hank has your back just in case though.
“Ive been soldering alot of FPV drone boards, this looks like something ive never soldered before. Its dark grey, not shining like normal lead.”
Yes, and you haven’t seen it much because you shouldn’t see it often, at least not in quality gear. In general, “cold solder joints”, which cause all manner of problems, are in fact dull and ‘grey’ and not ‘shiny’, and that’s exactly how they’re typically best identified when troubleshooting, etc. They should be shiny if soldered properly, and will be dull grey if they’re not. It is an indicator of construction quality (or lack thereof).
I’m surprised that spring didn’t come off on the first day of summer…… 