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ArcticMyst Security by Avery

My first laser build!






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the current was set to 120mA

Set with test load? Because the IC on the driver will eat up some current also, so unless you used a dummy load to set the current, your diode wasn't seeing 120ma. But, I have a PHR set at 110ma, and it lights matches and engraves just fine.
 
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ok.. listern, i read you thread and you really arnt getting it right! (not to be rude!). Basic electrons tells u that a test load is needed inorder to get an accurate and true reading of the ma running through the system when under "load", hence the name dummy load. get one of these, you can buy or make them and they are relatively inexpensive! try darkarmyofone or scopeguy20 for a new diode, they live in usa and usually have spares that they can send out for ya. Otherwise try www.darklasers.com.

If you ever try setting the current, remove the diode, install test load, attach miltimeter, bump up current, then remove test load, short the capasitors THEN attach the diode.

hope that helped -Adrian
 

diachi

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i was reading the rkcstr Microdrive instructions and it says that if I under volt the driver, It will NOT harm the diode or driver at all.
so what did you mean by I'm risking damaging the diode?


You can't risk the diode by giving the driver too low of a voltage, all that will happen is the driver won't regulate so the diode won't power to full power/power at all.
 
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ok.. listern, i read you thread and you really arnt getting it right! (not to be rude!). Basic electrons tells u that a test load is needed inorder to get an accurate and true reading of the ma running through the system when under "load", hence the name dummy load. get one of these, you can buy or make them and they are relatively inexpensive! try darkarmyofone or scopeguy20 for a new diode, they live in usa and usually have spares that they can send out for ya. Otherwise try Welcome to Dark Lasers!.

If you ever try setting the current, remove the diode, install test load, attach miltimeter, bump up current, then remove test load, short the capasitors THEN attach the diode.

hope that helped -Adrian

Yes, that actually helped a lot Adrian.
But even though I didn't use a test load, is the difference large enough to the point where my laser couldn't even light a match?
I'm still not sure if it's something I did wrong during the build, or if it was a weak diode, because I couldn't even light a match from point blank range (focused).

Thanks for your input. I'll use a test load this time haha.

You can't risk the diode by giving the driver too low of a voltage, all that will happen is the driver won't regulate so the diode won't power to full power/power at all.

Okay, thanks for clearing that up for me. I was pretty sure you couldn't risk the diode by under volting it, but someone told me you could, so i was confused.
 
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Okay, thanks for clearing that up for me. I was pretty sure you couldn't risk the diode by under volting it, but someone told me you could, so i was confused.

I know I'm new here and diachi is extremely knowledgeable. I'm not trying to step on any toes here, but I got my information from the great Bob_Boyce:
(log from laserchat)

"BobBoyce>: I tested 5 of the rkcstr drivers, they all dropped out between 2.0 and 2.2 V over the LD voltage, and they were unstable in regulation below about 2.5V over LD voltage"

"BobBoyce>: a 7.2V pair of lithiums in series will barely make it, and it will go unstable as the cells drop below 7V
bryce007>: fully charged is 4.2v each
BobBoyce>: yes, but that plateau is short-lived
BobBoyce>: the rkcstr can fry the LD when it goes unstable"

I damaged the window on my PHR for exactly that reason. Now I do currently have 3 rkcstr drivers that I use, but I use 3x 3v CR2 for blu-ray, and 2x RCR123a 3.6v for red.
 
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actually i just rememberd something..
There was no spring in my aixiz module.. Which is probably why i couldn't focus it properly.
It was super loose when i was trying to focus it.
That is probably why it couldnt burn! =[
 
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well.. you said you had it at 120ma.. that is more then enough to start getting some burning. there are many reasons that could constitute to not burning/lighting a match, they are:

1) batteries are half dead
2) not focused to a pin point (you must get it as small as possible)
3) not holding it still
4) your lens is dirty
5) not enough current
ect
ect
ect


there are soo many variables... you got to be sure that its that exact one, before you start tinkering around with it! and try to rule the possibilities out one at a time that way you can ask for help and give a more accurate description, of symptoms...

btw i am happy to help any one out.. please dont hesitate to ask! -Adrian
 

sbdwag

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i thought the rkcstr automatically cuts most power when the batteries get to a certain voltage?
I dont have anything to check the voltage of my batteries with.
I was just assuming that I could just use it until the laser starts to dim and then charge the batteries.

Paintbru5h

3.5 volts is the low end of L-ion's charge graph. When fully charged you will get 4.2 volts each so you will start out with 8.4 volts. With the millamps you will be drawing from these batteries you will probably get a couple of hours of use before they get close to the 3.5v cutoff. I never let mine discharge that much. If you are worried about oscillations you will have to monitor voltage with a voltmeter but I would not worry about it to much.

There are more immediate concerns using unprotected L-ion batteries. 10440's cannot be protected so you will have to monitor voltage anyway. Li-ion batteries can do something called rapid disassembly. Basically they can catch on fire and burn like a road flare generating highly poisonous gases. This can be caused both by low voltage (over discharging them) and overvoltage (over charging them by using a cheap or defective charger). In a air tight flashlight with o-rings they can explode like a pipe bomb.

For example the difference between 4.2 volts charge and 4.4 volts charge can be enought to start a fire. Only .2 volts difference also anything over 4.2 volts can damage your batteries.

Rapid disassembly is not something you want to happen in your house. It might start a fire for one thing and another you will have to immediatly air out your house with fans. Believe me I know !

Using single cell L-ion batteries is cutting edge. The only people that are doing it are the LED Flashlight hobbyist. So you need to go to the Candlepower forums and study up before you start using Li-ions.

Also rapid disassembly can be caused by stacking a newly charged battery in with a discharged one. If you are going to use them in pairs charge them in pairs too.

Basically Single cell Lithium ion batteries are cutting edge and you need to do your homework

Let me put it this way. If you have a Li-battery burn in your house. Everyone is going know it. It burns white hot and will start a fire easily. And it generates a lot of very noxious poisonous fumes that you are not going to be able to cover up. Everybody will have to get out of the house and all the windows will have to be opened and fans turned on.
Most of the time rapid disassembly occurs when charging. But I had it happen to me when I put one of the cells in backwards and it shorted out on the flashlight.

BE CAREFUL

Regards
sbdwag
 
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Paintbru5h

3.5 volts is the low end of L-ion's charge graph. When fully charged you will get 4.2 volts each so you will start out with 8.4 volts. With the millamps you will be drawing from these batteries you will probably get a couple of hours of use before they get close to the 3.5v cutoff. I never let mine discharge that much. If you are worried about oscillations you will have to monitor voltage with a voltmeter but I would not worry about it to much.

There are more immediate concerns using unprotected L-ion batteries. 10440's cannot be protected so you will have to monitor voltage anyway. Li-ion batteries can do something called rapid disassembly. Basically they can catch on fire and burn like a road flare generating highly poisonous gases. This can be caused both by low voltage (over discharging them) and overvoltage (over charging them by using a cheap or defective charger). In a air tight flashlight with o-rings they can explode like a pipe bomb.

For example the difference between 4.2 volts charge and 4.4 volts charge can be enought to start a fire. Only .2 volts difference also anything over 4.2 volts can damage your batteries.

Rapid disassembly is not something you want to happen in your house. It might start a fire for one thing and another you will have to immediatly air out your house with fans. Believe me I know !

Using single cell L-ion batteries is cutting edge. The only people that are doing it are the LED Flashlight hobbyist. So you need to go to the Candlepower forums and study up before you start using Li-ions.

Also rapid disassembly can be caused by stacking a newly charged battery in with a discharged one. If you are going to use them in pairs charge them in pairs too.

Basically Single cell Lithium ion batteries are cutting edge and you need to do your homework

Let me put it this way. If you have a Li-battery burn in your house. Everyone is going know it. It burns white hot and will start a fire easily. And it generates a lot of very noxious poisonous fumes that you are not going to be able to cover up. Everybody will have to get out of the house and all the windows will have to be opened and fans turned on.
Most of the time rapid disassembly occurs when charging. But I had it happen to me when I put one of the cells in backwards and it shorted out on the flashlight.

BE CAREFUL

Regards
sbdwag

Thanks for the info and the warning sbdwag. I'll be sure to be careful with these batteries now.
 
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well.. you said you had it at 120ma.. that is more then enough to start getting some burning. there are many reasons that could constitute to not burning/lighting a match, they are:

1) batteries are half dead
2) not focused to a pin point (you must get it as small as possible)
3) not holding it still
4) your lens is dirty
5) not enough current
ect
ect
ect


there are soo many variables... you got to be sure that its that exact one, before you start tinkering around with it! and try to rule the possibilities out one at a time that way you can ask for help and give a more accurate description, of symptoms...

btw i am happy to help any one out.. please dont hesitate to ask! -Adrian

1) Batteries were at 4.09V each when checked.
2)I believe this is the problem. As I said, there was no spring in the aixiz module which probably made it even more difficult to focus.
3) I had it set on a flat surface and the match was held with "helping hands" (the tool)
 
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yeah... i know.. im just saying, before you go tinkering with a laser.. you should go through a check list, checking all the symptoms, then asking for help, then trying to fix it! just so you can be 100% sure, before you go off and adjust things!

-Adrian
 
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well now I know after killing a diode... lol
its okay.
Learning Curve! haha
 
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Can anyone tell me what the best way to focus the blu ray is?
I noticed that when I did have it focused for one object, it wasn't focused for something at a closer/further distance. Is it supposed to be like that?
On the youtube videos I see, people who burn matches/pop balloons don't need to refocus.
 
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LMAO... focus is exactly that.. it focus the dot to a very small point at different distances.. eg lens screwed in all the way = small dot far away, but 3/4 the way in = small dot about 4-5 cms away.. get it? do you have any saftey glasses? if so then put them on and you will see a the dot.. keep turning the lens in or out till it is as small as possible at the distance you would like... in terms of green lasers, their divergance is very small so it is easier to burn things at longer distances, but blu rays work differently, u need to focus the lens for the distane your burning at!
 




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