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Many questions about first 9mm 445nm build!

brunes01

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Re: New 9mm 445 diodes

Hi!

Ouch! All that stuff sounds terribly painful!

I hope I will not find out myself how painful! :(


BTW my batteries and charger have arrived! These are huge! :D


I read about the copper heatsink from Survivallaser, that it has a thermal conductivity of 355 W/m-k. Is that good?

And what about the mass or weight of a heatsink? Heavier = better?

Greets brunes01
 
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ApexProxy

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Re: New 9mm 445 diodes

I'm not sure what grade of copper Gary uses but pure copper usually has a thermal conductivity of about 400 W/m-k. Copper is extremely good in terms of thermal conductivity as well as volumetric heat capacity and is basically the best material possible aside from pure silver.

If you are comparing two heatsinks of the same material then more mass is better but if you are looking at different materials mass actually means nothing. What matters is called volumetric heat capacity which is how much heat the material can store in a given volume. When we make heatsinks the limiting factor is volume so the better a material is at storing heat in the same volume the better it is as a heatsink.

Our goal with the heatsinks we make in handheld lasers is to be able to move the heat away from the diode and into the host as fast as possible as well as needing the heatsink to be able to store as much heat as possible before raising in temperature.

I have simplified things a little here to make it easier to explain and understand but I did make a painfully detailed post on this subject not all that long ago if you want to try to dig it up.
 

DTR

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Re: New 9mm 445 diodes

I think that host he was looking at was the stainless steel version so pretty much he is just looking at the capacity of the copper. My experience with SS hosts is that the heat just does not move into them with any notable efficiency. Basically the heat sink is isolated and just a storage container instead of a transfer medium. But as stated that heat sink is good enough size for the runtime he is expecting.:beer:
 

ApexProxy

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Re: New 9mm 445 diodes

DTR, that's exactly what I noticed. Stainless Steel has a rather deplorable thermal conductivity so I would advise a 60 second on and 30 second off duty cycle or en even higher off. I noticed my SS took longer than my other hosts to cool down.
 

brunes01

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Re: New 9mm 445 diodes

Hi!

So the stainless steel host in my build, with it`s low thermal conductivity, is not the best option, because it won`t allow the heat to get out.

The best option to get the heat away then should be a host made of copper (beside silver) too, did I get that right?

Anyway I like the look of stainless steel! :D

Will it be a benefit, that the heatsink will not be surrounded completly by the steel host?

I asked about the mass of the heatsink, because I read in another thread for a mag-light host build, that a heatsink of almost 3 times the weight compared to another build was used. So my thoughts were the more mass/weight the more heat can be taken away from the diode.

Sure you can`t compare aluminium to copper when it comes down to weight! ;)


BIG NEWS!!!

My diode from DTR arrived today after just 7 days!

Thanks to DTR for his great service!


Greetings brunes01
 

ApexProxy

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Re: New 9mm 445 diodes

The Stainless Steel host is not thermally optimal but I agree they do look great. For your use it will be fine though. The heatsink isn't completely surrounded by the host but there isn't a whole lot of surface area exposed to release heat. Its still not much of a big deal though. My old SL SS did great but did get reasonably hotter than my other hosts so just keep that in mind when you use it.

The more material in a heatsink the better, its all about volume. I would say that an aluminum heatsink would probably have to be 20-30%(rough guess) larger in volume than a copper heatsink to be able to perform roughly the same.
 
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brunes01

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Re: New 9mm 445 diodes

So what about drilling some holes in the steel host?

Not to get more running time at all costs, just to get a little better cooling!

And it would make the look of the build more unique when the copper heatsink "shines" through.
 

ApexProxy

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Re: New 9mm 445 diodes

Drilling holes wouldn't really help, at least not enough to make any noticeable difference. Also, be warned that copper does not retain its shiny copper surface at all if you have it in your pocket much or if you touch it at all.
 

brunes01

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Re: New 9mm 445 diodes

I thought it would just look cool to make it look like a "machine gun barrel" at the front.
 
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DTR

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Re: New 9mm 445 diodes

Just build it. Don't overthink it you will be fine. Last thing you want is to get crazy in modifications and mess something up.:beer:
 

brunes01

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Re: New 9mm 445 diodes

Yes. I think that would be the best way to go!


edit: The host is on it`s way!

Hope it will arrive next week, if it comes as fast as the diode from TDR!
 
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brunes01

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Re: New 9mm 445 diodes

Hi there!

Still waiting for the host!

So I was thinking about some other stuff, that could be done!

I came across the idea to get a labby style heatsink as well for my laser!

Is the module that came with the diode called a 12mm Aixiz Module?

I have found several threads about labby style heatsinks on the forum, but wasn`t sure about that!

BTW is it possible to make the module easily removeable from the host, so I can also use it in a labby style heatsink?

Maybe with a plug in connection?

Greets and thanks
brunes01
 

ApexProxy

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Re: New 9mm 445 diodes

You likely did get a 12mm aixiz style module unless you got a bare diode.

I have two lab style heatsinks which are great since I can run a diode for near unlimited amounts of time off my power supply and do any amounts of testing needed.

I wouldn't ever suggest removing a diode too often from a host since diode are far too sensitive for that. Frequently removing a diode from its driver may also cause damage to either one. The electronics are small and sensitive to electrostatic discharge as well as any kind of power spike associated with connecting and disconnecting. IMO, once a build is complete in a host it isn't really taken apart unless you are going to change something out. Its just too risky.

I would suggest if you want a lab style laser then make one separate from your handheld. You will also need a power supply of some kind to run the diode.
 

brunes01

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Re: New 9mm 445 diodes

Hi!

Yes I didn`t forget about the power supply!

Well, it`s just an idea at the moment!


I didn`t mean to seperate the diode from the driver.

The piece I got from DTR is already soldered to the driver.


I thought to put the whole module (picture) in a labby style heatsink! Diode +driver!

Wouldn`t that work?


Greets brunes01
 

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ApexProxy

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Re: New 9mm 445 diodes

That could work as long as you remember not toput any straign on the diode pins since the driver is soldered directly to it. Also remember you will likely not get unlimited full power runtimes because of the whole driver heatsinking thing.
 

brunes01

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Re: New 9mm 445 diodes

That`s right! So the limit would be the driver then!

Maybe something like that could work with a 8V power supply?

Heat Sink for 12 mm Modules


But first of all! Can the 12mm module being "plugged" to the power supply of the steel host? Or maybe clamped instead of being directly soldered? Just like in the picture I have found from another build.

If it will not be possible to change the 12mm module easily between steel host and labby heatsink, it`s the end of the story!


Greets brunes01
 

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