Learn From Mistakes That Can Happen To Anybody...

[grainde]

Wow, didn't see this thread first time around. Well I'll add this info to the thread just because of how strange it is. No one will be doing this these days. Long ago, I was scratch building an argon laser and it was a design similar to the old Scientific American magazine article. I purchased a glass diffusion pump for bringing the gas laser to an extremely low pressure. This was a "mercury" diffusion pump. I purchased 2 pounds of mercury to run the pump. The mercury was stored in a glass bottle inside a brown paper bag. The laser was being built inside of my garage with concrete floor. Forgetting how heavy the bottle of mercury is, I picked up the brown paper sack and "crash". The bottle ripped through the sack and burst giving me the worst mercury clean-up ever. I had to sweep carefully with a hand broom and used sheets of copier paper to scoop and put the mercury into a beaker. It was the most tedious recovery operation and the scare about having lots of toxic mercury out in the open. I decided that if gold miners could be around the stuff that I wouldn't worry too much. I was ok, but you can't be too careful with mercury. Now I have a blue 445nm Class IV running on 3XAAA primary batteries. Much easier than an argon from scratch. Thanks Dave!

Hey Millirad how long ago was the spill? If it was only recent, Id head on down to a pharmacy to pick up some Sulphur (flowers of sulphur) to sprinkle over the spill area. Leave for a while (30 mins or so) and then sweep up and dispose of properly, as the HgS formed is toxic chemical waste. Pure mercury is a problem due to its vapour pressure ie it evaporates. Due to the small size of the tiny residual droplets from a spill, the high surface area they afford accelerates evaporation. This means you can end up breathing in relatively high concentrations of the vapour esp. if in a confined environment and or badly ventilated area. I probably dont need to reiterate quite how toxic Hg is! Good luck!

 

[Keiichi tsuchiya]

A little experience here ... Last time i was playing with my 100mw laser and i got hit in the right eye and for my good luck i wasnt wearing my goggles at that time ...): ..... What a pain !!! ... It feelt like something was stuck on my eye for 6 HOURS !! hopefully the battery was almost death .. At that time my laser wasnt outputting 100mw it was mor elike 5mw or less but still!!!!!!!! That radiation hurt a lot !!!

 

[Kizdawg]

Ok Well I have to finally post here... I baught a pl450 from DTR last week and it arrived a couple day's ago. I baught a 5.6mm diode press tool and decided to drill a hole in the back of it to press in the 3.8mm diode and use it backwards I had 1.98, 2.38 and 2.78mm drill bit to choose from and I started with the smaller 1.98mm.. I thaught it was all lined up but I guess it wasnt and when I pressed it into the RHD Mod3 it was damaged... I used a flaminpyro diode removal tool host in the lense cavity while pressing. I have a couple more coming cant wait to see... but there is no life in that little guy... RIP!

 

[Videogamer555]

Re: Mistakes That Can Happen To Anybody...

Regarding the opening post of this thread:
That's odd. A low battery means less power to the diode and so should have less potential to damage the diode. And if it has a shutoff circuit, then that even MORE is a protection to the diode. Also how does removing a diode from its housing destroy it, unless you had static electricity on your hand when handling it (hadn't properly discharged your body's charge prior to handling the diode)?

A little experience here ... Last time i was playing with my 100mw laser and i got hit in the right eye and for my good luck i wasnt wearing my goggles at that time ...): ..... What a pain !!! ... It feelt like something was stuck on my eye for 6 HOURS !! hopefully the battery was almost death .. At that time my laser wasnt outputting 100mw it was mor elike 5mw or less but still!!!!!!!! That radiation hurt a lot !!!

What wavelength was it?

Also I wouldn't think it would hurt, more like just be uncomfortable from brightness (not truly cause physical pain).

I bet you were more scared that you might have lost your eyesight, not so much that you were truly in pain.

 

[Kizdawg]

MW5 hurts your eyes after a couple hrs too..

a 100 mw laser can blind you.. I dont use my goggles as much as I should. spent 170$ on them but atst I'm old, so if I lost my eye because I played wrong I can take the lump... any of you not willing to take the lump of a lost eye buy the goggles!

 

[Videogamer555]

How do electrolytics regain charge, even after fully discharged and shorted, once the shorting wire is removed? Where's the source of the electric charge, when its not in any circuit?

 

[nouthyella]

How do electrolytics regain charge, even after fully discharged and shorted, once the shorting wire is removed? Where's the source of the electric charge, when its not in any circuit?

Static electricity can cause the cap to become charged when it touches one of the wires. If this happens frequently the cap may become significantly charged. Shorting it prevents charging due to any reason.

 

[Videogamer555]

Static electricity can cause the cap to become charged when it touches one of the wires. If this happens frequently the cap may become significantly charged. Shorting it prevents charging due to any reason.

Where does the static come from? Shuffling your feet on the carpet while wearing socks, and then touching one terminal of the capacitor while the other terminal of the capacitor is grounded?

 

[aluminous]

I'd like to share mine after burning a hole in a poor $100 445nm diode's window. :cryyy: Here's my story:

It was my first build, so I handled the diode very carefully while installing it. It worked. I owned a >2W laser... for about 20 minutes. While focusing, the beam suddenly got very weak. I blew off the lens and tried again that was the end.

Turns out COD was a piece of glue (my lens was salvaged) that fell onto the diode window and burned a hole almost immediately.

Lessons learned:

1. Make absolutely sure there's nothing floating around inside your module.
2. If your beam changes suddenly, cut power immediately and don't turn it back on hoping the issue magically goes away.

 

[Blord]

That was the the 9mm diode ? Why did you remove the window in the first place ?
Poor thing

 

[aluminous]

It was the 9mm, and for a few minutes it was beautiful (from behind goggles).

No-- I didn't remove the window. (I was nervous taking it out of the packaging, let alone cutting any pieces off). The glue burned the window itself, and by the time I knew what was happening the diode LED'd.

EDIT: Damage shot

 

[ryansoh3]

Love this thread.
Here's mine:
A couple weeks ago, my friend and I were checking out a 2W 445 laser. We both had goggles of course. I warned him many times about the dangers, and he said that he fully understood.

Well, turned out that he didn't.

I turned on the laser and placed it on a table. We were admiring the sweet blue beam. I then heard a crackle on the other side of the room, and went to check it out. When I had my back turned, I heard a sudden "GAHHH!!" from him.
'Oh crap,' I thought. 'He must have blinded himself or something.'
Thankfully(?), it only turned out that he had put his hand on the way of the beam and burned himself.
Here's the interesting part: I asked him why the heck would he do such a thing, and he replied, "It just looked like a beam of light. Thought it was cool." :facepalm:

A few days later, turned out that he had a blister on his hand.

Moral of the story: Never let your "un-laser-educated" friend, no matter how trustworty, be near a functioning laser.

Cheers.

 

[Seoul_lasers]

Love this thread.
Here's mine:
A couple weeks ago, my friend and I were checking out a 2W 445 laser. We both had goggles of course. I warned him many times about the dangers, and he said that he fully understood.

Well, turned out that he didn't.

I turned on the laser and placed it on a table. We were admiring the sweet blue beam. I then heard a crackle on the other side of the room, and went to check it out. When I had my back turned, I heard a sudden "GAHHH!!" from him.
'Oh crap,' I thought. 'He must have blinded himself or something.'
Thankfully(?), it only turned out that he had put his hand on the way of the beam and burned himself.
Here's the interesting part: I asked him why the heck would he do such a thing, and he replied, "It just looked like a beam of light. Thought it was cool." :facepalm:

A few days later, turned out that he had a blister on his hand.

Moral of the story: Never let your "un-laser-educated" friend, no matter how trustworty, be near a functioning laser.

Cheers.

And that burn won't heal like a normal burn either. With a laser (especially 445nm and lower nm) the burns can get quite deep even with brief exposure. I managed to get one on my finger from doing an experiment with resorcinolphthalein dye (Fluorescine) and upon focussing the laser, my finger accidentally passed trough the tightest point of the beam. There was a little pop of flame and the smell of burning flesh. Nice sized (big) blister the next day. It took about a month and a half to heal. Hurt like hell. never again. Fingers heal, eyes don't.

 

[ryansoh3]

upon focussing the laser, my finger accidentally passed trough the tightest point of the beam. There was a little pop of flame and the smell of burning flesh. Nice sized (big) blister the next day. It took about a month and a half to heal. Hurt like hell. never again. Fingers heal, eyes don't.

Ouch!
Were you using your 2.7W peak laser? That's a lot of energy concentrated into a very very small area. That sucker must have packed a punch! :gun:
I think my friend held his hand in front of a parallel beam for about two for three seconds before he pulled away in pain.
Just wondering what your reaction time was.
Thank goodness to both you and my friend that it wasn't the eye.

Great to see you again. :wave:

 

[daawood123]

here's my embarassing experience:
so I got a PHR diode (not expensive I know) and I was so excited , I forgot to install the diode into the aixiz head before soldering, so after soldering was done, I took a step back, realized what I had just done, and was like WTF. After many failed attempts to press the diode into the module, I decided to try pull the soldered wires off, well, long story short, all 3 pins got pulled off, meaning I now had no way of soldering to the diode.

It was my (well, going to be) bluray build and is also my first ever diode that I killed.

Sad times

 

[Quetzal]

I was screwing the front end of my F22 on after putting in a fresh battery, when the laser came on and burned my hand (not badly, but I dropped the tail section).

I had forgotten that I had left the switch in the "on" position after the battery went out.

Lesson here is to never have and part of your body in a position where it could get burned if the laser was on.