Safety pin idea/mod (pic heavy)

Hi everyone first post here,

First of all sorry for the crap pics, I used my phone camera, lesson learned doh!

I have a waterproof host for my 445nm 1W blue laser but was worried about the thing turning on in my pocket and burning a hole or the kids getting hold of it and blinding themselves and wondered if I could create some sort of safety for this. And came up with a pretty easy solution.


However this will not be waterproof anymore, it’s a function I never used anyway.

I went for a safety pin idea and figured the easiest thing to use was a 3.5mm phono jack socket which I salvaged from an old sound card


I removed all the metal contacts I didn’t need, as I didn’t want these shorting out in places they weren’t supposed to, the only ones I left in were the ones that connected to the end and the middle contact on the plug.

The good thing about this connector socket is these were exposed on either side, one side I cut off and the other I bent over so it lined up with the switch contact on the end, I also filed a corner off so it was shaped better for a flush mount into hole.

I then drilled my hole in the end cap, I measured and drilled this so it would be flush up to the plate that holds in the switch.


Then I placed my socket in the hole, I also cut a piece of plastic and placed behind it to stop this from being pushed back inside.


this contact lined up perfectly with the switch contact on the bottom, I then screwed the plastic plate back on witch holds the connector for battery, this connector also lined up perfectly with the exposed leg on the top of the socket.




this then required the battery to be located closer to the head of the laser or the end cap would not fit on, safer removing the head of the laser this had some rubber washers in there to stop the weight of the battery compressing the spring and losing contact.


I removed all of these but one.


laser all put back together.


I then had to make the pin out of a stereo 3.5mm jack plug, I bent all the contacts over inside and soldered together, cut the casing down and glued a bit of plastic on the end to neaten it up.


After realising I had no where to store my little yet I devised a holder for my keyring, to keep it safe when I'm not using it. This was made out of another socket I found lying about with a hole drilled in the end and a small keyring passed through it.




Mission accomplished, this won't work without the key iserted in the hole.

Nice work, reputation given.

If the weight of the battery is compressing the spring too much, try adding a drop of superglue to the base of the spring, where it's soldered to the pin or whatever, to keep it from snapping when pressure is put on it.

Everything else looks solid, and your reasoning behind the mod is admirable.

That is a great idea! Very out-of-the-box and creative.

+1 for you! :gj:

I gotta say, it's refreshing to see a newb with great ideas instead of "can I burn with this?" and "I hear I can pot-mod this laser to double the power!!" :crackup:

Hang around here; we need more creative members in our ranks. :beer:

Excellent first posting.
A penchant for safety.
A detailed picture rich example of applying the philosophy.
No bull included...
+1 for you.
:kewlpics:

I don't rep often but for a great safety mod you have to get something.
Very nicely done, I hope others try this mod too. A 2.5mm jack could even leave more threads on the tail.

Thanks guys for the great welcome :thanks:

Eudaimonium said:

If the weight of the battery is compressing the spring too much, try adding a drop of superglue to the base of the spring, where it's soldered to the pin or whatever, to keep it from snapping when pressure is put on it.

Click to expand...

Good tip, will do that as that spring is compressed as much as it will go now I bet there is quite a bit of weight on it, also thought about maybe cutting it down?

HaloBlu said:

A 2.5mm jack could even leave more threads on the tail.

Click to expand...

Great minds think alike, I actually went to my local electronics store to get a 2.5mm as this was my original intention however they only had ones with a metal body and this would have shorted out on the case so went with the slightly larger one instead. I know you can get them off the internet but I am too impatient.

A 2.5mm would be better as it's a rarer connection, when you think how many devices use a 3.5mm, headphones, microphones, chargers etc... would stop people who didn't know any better trying to plug these in.