2W 445nm WF-900L build in progress

[justinjja]

Im going to be finalizing my 2W build tonight,

Im using a jayrob maglite heatsink,
Along with a custom LM350T Driver.

Initial Pics:

Test of my diode, at 1.7A

More to come later tonight

 

[justinjja]

Custom Spring assembly:

Driver mounted to Heatsink:

 

[lazeerer]

You are shorting the Regulator to the Heatsink and the Negative path.!!!!!

Seems you are fallowing my thread here:
http://laserpointerforums.com/f52/2...f-009-mohrenberg-heatsink-tutorial-59251.html

I clearly state that the regulator must not make contact with the Heatsink and or negative path since the Back of the Regulator is part of your output. Make sure to correct this before you turn it back on.

It must be insulated.

 

[jayrob]

Or if you have a thick enough layer of thermal adhesive to isolate the regulator from the heatsink, and then just not use a screw mount.

Looks like that heatsink got kind of scratched up...

 

[lazeerer]

Or if you have a thick enough layer of thermal adhesive to isolate the regulator from the heatsink, and then just not use a screw mount.

Looks like that heatsink got kind of scratched up...

Yeap exactly what i did and what i recommand in the thred.. I put a thick layer down of thermal adhesive to insulate it. This is the best option IMO.

 

[justinjja]

You are shorting the Regulator to the Heatsink and the Negative path.!!!!!

Seems you are fallowing my thread here:
http://laserpointerforums.com/f52/2...f-009-mohrenberg-heatsink-tutorial-59251.html

I clearly state that the regulator must not make contact with the Heatsink and or negative path since the Back of the Regulator is part of your output. Make sure to correct this before you turn it back on.

It must be insulated.

I hadn't seen your thread actually, looks pretty good.

I'm fairly sure the heatsink won't be electricly connected to the head of the flashlight on my build a least. We will see...

And the heatsink looks better in person

 

[jimdt7]

If you have a multimeter with a continuity option, you can test it !
It is safer and you wont kill your diode

Jim

 

[justinjja]

I did test it

The original flash light had 2 springs, one for positive and one for ground,
If the heatsink was connected to ground via the head, then the ground spring woulnt have been nessasry...
I removed the spring, and the flashlight didnt turn on, so to me that means the head is not electricly connected to the ground...

 

[justinjja]

The heatsink was a little lose in the head, because I took out the glass lens that was originaly on the flashlight.
In need of a spacer, I cut up a couple stock maglite reflectors, they were just the right size, heatsink is now nice and snug.

lol



EDIT:
Pics of the completed build (from my phone)

]

Ill get some better ones up, along with beam shops later, after I finish having some fun

 

[jayrob]

Yes if your heatsink is electrically isolated from the host, it's fine, but the test of your flashlight not working is not where the proof is...

Flashlight emitters are normally case positive, and they are already electrically isolated from the heatsink/reflector in their mounting.

Just good advice to double check so that you don't end up killing your diode...

 

[justinjja]

Ya, the laser is working... so it isnt shorting.

Also, if it was to short, It would short out across the LM350, not my diode. So it wouldnt hurt anything, it just wouldnt work.

 

[lazeerer]

I did test it

The original flash light had 2 springs, one for positive and one for ground,
If the heatsink was connected to ground via the head, then the ground spring woulnt have been nessasry...
I removed the spring, and the flashlight didnt turn on, so to me that means the head is not electricly connected to the ground...

But there is a chance of the anodizing in some spots are not as good and can short the host.
Especially around the threading.

Ya, the laser is working... so it isnt shorting.

Also, if it was to short, It would short out across the LM350, not my diode. So it wouldnt hurt anything, it just wouldnt work.

It will still work but wont last long. Thats from Experience.!

Its your laser I cant make you do anything.:beer:

For the record though it will kill your diode.

The case of the Lm350 is part of your + out that goes to the diode + Pin.

Since you have the LM350 connected to the back of the heatsink the + diode pin will connect with them Negative input. Which will cause a short.


Take it from Experience. The laser will still work if its shorted like this but will heat up much faster and die withing 20 minutes. It took me 2 diodes to figure out what i did wrong at the time.

Do what you want. Iam just trying to help from my mistake.


Nice build though.:beer:

 

[justinjja]

For the record though it will kill your diode.

The case of the Lm350 is part of your + out that goes to the diode + Pin.

Since you have the LM350 connected to the back of the heatsink the + diode pin will connect with them Negative input. Which will cause a short.

The case on an lm350 or lm317 is v-out, but I have the circuit set up as a current source,
so the diode is actually connected to the adjust pin.

If it were to short out about several amps would flow through the v-in pin to the v-out tab to ground,

But as I regularly check the temperature of my heatsink, I would notice.


Never the less, once I get back to my dorm room in lubbock in a few weeks with my "full arsenal" of electronic parts, i will replace the screw with a layer of not-conductive arctic silver epoxy. :beer:

 

[lazeerer]

The case on an lm350 or lm317 is v-out, but I have the circuit set up as a current source,
so the diode is actually connected to the adjust pin.

If it were to short out about 5A-10A would flow through the vin pin to the vout tab to ground,

But as I regularly check the temperature of my heatsink, I would notice.


Never the less, once I get back to my dorm room in lubbock in a few weeks with my "full arsenal" of electronic parts, i will replace the screw with a layer of not-conductive arctic silver epoxy. :beer:

Your Diode + Pin is attached to the adj pin of the LM350 but also the Out pin of the LM350 since you have a resistor there to set the currant. Hench why iam saying it will short.

To set the currant on the LM350 you put a resistor cross the Adj and the Out pin. So they are connected.

The case of the LM350 is connected with your v-out and with the resistor there lso connects to the Adj--pin.

So if that makes contact with the Neg input it will short.

It will still work but will not last long.

There is really no way to test and see if its shorting with the host unless you test every spot on the host where the heatsink is making contact with. Which is impossible to do.

 

[justinjja]

Your Diode + Pin is attached to the adj pin of the LM350 but also the Out pin of the LM350 since you have a resistor there to set the currant. Hench why iam saying it will short.

To set the currant on the LM350 you put a resistor cross the Adj and the Out pin. So they are connected.

The case of the LM350 is connected with your v-out and with the resistor there lso connects to the Adj--pin.

So if that makes contact with the Neg input it will short.

It will still work but will not last long.

There is really no way to test and see if its shorting with the host unless you test every spot on the host where the heatsink is making contact with. Which is impossible to do.

Actually it is pretty easy to check if there is any shorting,
all I have to do is remove the tail cap, and measure the current from the battery to the case, if it is 1.7A, (and it is) then there is no shorting happening atm.

 

[Mohrenberg]

Throw on a 12ohm resistor and get that thing to >2W