Low-powered DT0811 for a prop (noob-alert)

[wolfblue]

Plus, I don't think you would want to be swinging a 6x around in public. Worse ... somebody could pick it up that doesn't know that its actually dangerous.


Or for $15 you could get a PHR and turn up the power after your finished with the prop, as a pointer.

 

[8tyeight]

I would just mod a red laser sight from DX, the switches are interchangeable. If you choose to try this method, make sure you get one with a universal mount. Unless of course your prop has a picatinny rail.

Link to gun sights: www DOT dealextreme DOT com/products.dx/category.914 ......well sort of, I dont have ten posts yet.

 

[Icetigris]

I would just mod a red laser sight from DX, the switches are interchangeable.  If you choose to try this method, make sure you get one with a universal mount.  Unless of course your prop has a picatinny rail.  

Link to gun sights: www DOT dealextreme DOT com/products.dx/category.914 ......well sort of, I dont have ten posts yet.

Well, since I already bought the circuit components and the Aixiz housing, it isn't really worth it to get one of these. Though looking at the gun sights, I now know that the little grey thing on the scope is the laser switch. Good to know!

 

[Icetigris]

I hate to bump my thread, but before I crack open this sled, does anyone have a step-by-step picture or perhaps video tutorial of harvesting the DT0811 diode from start to finish, including the heatsink step? I'm really paranoid about breaking this thing.

 

[Icetigris]

Alright, well I finally got to harvesting! I don't have the tools I need at school to free the diode from the little heatsink, but I'm going home for spring break tomorrow, so I may be able to locate a metal file or at least go get one. Daguin, you were right about this heatsink being a pain in the ass.

I just want to note that I was wearing an anti-static bracelet that was hooked to my computer case the entire time, so I hope I avoided frying the diode via ESD. I'm also planning on desoldering the flexible PCB from the diode while the heatsink is still on, so this harvest won't be finished until after spring break, I'm afraid.  :'(

You can see how girly my hands are here. Dear god, my nails.

 

[daguin]

Alright, well I finally got to harvesting! I don't have the tools I need at school to free the diode from the little heatsink, but I'm going home for spring break tomorrow, so I may be able to locate a metal file or at least go get one. Daguin, you were right about this heatsink being a pain in the ass.
I just want to note that I was wearing an anti-static bracelet that was hooked to my computer case the entire time, so I hope I avoided frying the diode via ESD. I'm also planning on desoldering the flexible PCB from the diode while the heatsink is still on, so this harvest won't be finished until after spring break, I'm afraid.  :'(
You can see how girly my hands are here. Dear god, my nails.

In my mind it is the worst heat sink I've dealt with.

Peace,
dave

 

[wolfblue]

I get this one and other pain in the.... diodes out by gripping the heat sink with sturdy wire cutters. So that the cutters bite into the sides of the heat sink. I hold on firmly and carefully. Then I cut thru it with a Dremel Tool cutoff wheel. On both side down almost to the diode case. Then pop it apart with two needle nose pliers. The danger is that you don't hold the pliers good enough and fling the thing across the room, gouging the diode window at the same time. Or don't hold the Dremel good and walk the cutoff wheel across the diode window.
Others use a fine tooth hand saw like a jewelers saw or mini hack. Or ......a small file

--John

 

[Icetigris]

In my mind it is the worst heat sink I've dealt with.  

Great.

So how small of a triangular file do you use to cut through it?

 

[daguin]

Great.

So how small of a triangular file do you use to cut through it?

I think I used a 1/4 inch. It was what I had on hand.

Peace,
dave

 

[Icetigris]

So I finally got to getting the diode out of the heatsink. It was horrible, as warned. I ended up cutting into the top part a little more than I had wanted to, but the can seems okay. One thing I'm a little worried about is I was trying to push the diode in the aixiz housing (not all the way, just so it's in something and not floating around unprotected) and I made the flexible PCB remnants partially detach from the solder and I bent the pins a little. Do you think it looks okay or did I break it?

 

[BuildAbluraylaser]

I think I was lucky with my heatsink... My diode just popped right out! They're not that difficult, you can try using to pliers and twisting the heatsink... Also, one of you guys said you built a pointer for your 14 year boy I think ( weird, at 14 I already had built my own!), and it was set at 10mW and heating up after 3 minutes. Mine is at 50 and bearly heating up after 5 minutes... ???

 

[wolfblue]

... Also, one of you guys said you built a pointer for your 14 year boy I think ( weird, at 14 I already had built my own!), and it was set at 10mW and heating up after 3 minutes. Mine is at 50 and bearly heating up after 5 minutes... ???

Yeah, they kind of lost interest in electronics (I have two boys, 14 and 15). They were building analog and digital on breadboards when they were like 10, But now they just like girls and video games.

And I don't think I said that pointer heated up after 3 minutes. Its more like it takes 4-5 minutes before you can tell if it has warmed at all.


--John

 

[BuildAbluraylaser]

Ok ya

 

[Icetigris]

Should I be worried about frying the diode when desoldering, since I can't get any clips onto the pins? What do you guys use to desolder?

 

[wolfblue]

You should press the diode into the heatsink before soldering. If you need to remove the little circuit board from the diode, the best way is to hold the heatsink with a little vice or 3rd hand device. Then put the soldering iron in contact with the 3 pins, and apply a big glob of solder so that it envelops all three pins. Then pull the little circuit board off with small needle nose pliers. You MUST DO ALL THIS QUICK. It should be no more than 3-4 seconds. If it will take longer STOP, let it cool and try again in a few minutes. The bulk of the excess solder is wiped off the pins by the circuit board.

For other de-soldering needs, look into desoldering Braid (AKA Wick). Where you put the braid in contact with the solder you want to remove, and heat the braid with firm contact. So that you heat the braid and the solder joint at the same time. The solder will be pulled into the wick by capillary action. Then you just cut off that part of the wick when it cools and you ready to desolder again. This removes the bulk of the solder. You still may have to heat the pins to release the part, as a small bit of solder could remain. Hope this helps.


--John

 

[Icetigris]

I ended up being able to cut the PCB remnants off with an x-acto knife, though the old solder is still there. Does it need to be desoldered? If so, since I have some experience using copper braid to desolder, I'll go pick some up if I need to.

Now that I'm almost done with the non-circuits part (thanks for putting up with all my paranoia so far; you guys are great), I'm starting to think about questions for the actual circuit. How many mA should I give to the diode to get it around 5-10mW? I'm doing the DIY driver circuit from Phazonx's tutorial here except I'm going to actually solder the components to a generic PCB: http://www.metacafe.com/watch/1011559/diy_how_to_make_a_laser_diode_driver_circuit/

In the video, he uses a 25 ohm potentiometer; I have a really small 100 ohm one. Will this work? If not, do you know what resistance I would need in that part of the circuit to get the ampage I need for the wattage I'm trying for?