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ArcticMyst Security by Avery

How to Determine Duty Cycle

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If I actually needed more than 60 seconds on, on a regular basis, I would invest in/build a lab style laser with active cooling and full size (not smd) components.


GOOD ANSWER--;-)


Or just spend more on an expensive laser that has a longer run and shorter rest cycle. This is one of the reasons they are worth the extra cost. And they generally have a much better warranty and cust. service.

and overspec.

and come with safety eyeware-every laser. lots of good ones out there FS from members- still the best place to shop at LPF world.

hak
 





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GOOD ANSWER--;-)


Or just spend more on an expensive laser that has a longer run and shorter rest cycle. This is one of the reasons they are worth the extra cost. And they generally have a much better warranty and cust. service.

and overspec.

and come with safety eyeware-every laser. lots of good ones out there FS from members- still the best place to shop at LPF world.

hak

Hehehe I have that one covered already but I dont think you can see the beam for the 10600nm and it cost a lot of money + it is meant to cut sheetmetal...fun to play with but I NEED MORE!! :evil: lol

All of these posts are great and valid posts. Just trying to get started with a build someone else has already done to get some knowladge and experience under my belt before I really tear some stuff up or demolish some equipment :D

Another note I havent seen anybody say this is an old post or complain about talking about it so maybe it should be a sticky? Just a thought being that it is educational for the next "me" that comes along and is wondering the same thing.
 
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Another note I havent seen anybody say this is an old post or complain about talking about it so maybe it should be a sticky? Just a thought being that it is educational for the next "me" that comes along and is wondering the same thing.

How can you or anyone else consider this post/thread being old....
you started it 2 days ago....:thinking:

To have a Thread stickied it should contain exceptional and/or
important info for the LPF Community...

Most Laser Threads on the Forum are "educational".... only the
exceptional/important ones get stickied...

I see nothing exceptional on this thread... it just seems like
common sense to me...:cool:


Jerry
 

Benm

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If we sticky everything, there would be no room for new posts on the first page :)

I did, however, put a writeup online that i was working on, perhaps it will help explain the matter a bit further:

Merghart.com - Heatsinking laser reference

Its still only a scientific approach to the problem, so establishing the thermal resistance from host to ambient remains up to the reader... although there are a few examples in there to give you a rough idea.
 
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If we sticky everything, there would be no room for new posts on the first page :)

I did, however, put a writeup online that i was working on, perhaps it will help explain the matter a bit further:

Merghart.com - Heatsinking laser reference

Its still only a scientific approach to the problem, so establishing the thermal resistance from host to ambient remains up to the reader... although there are a few examples in there to give you a rough idea.

Good job on the writeup...

Jerry
 
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@OP - several members make HSs for many Cree Mods. The cost is usually much less than it would if it we were not forum members.

One good way to get a perfect fit is to send your Cree to a member to make you a HS- copper is best but more $ than Al.

some offer adding the driver/&pill for you and all you do is solder the LD to the driver. All of these guys have a good feel about duty/rest cycle as they make the HS and they use them. Most will tell you to always err to the side of more rest and less duty. And if you feel much heat on your hand its time to rest.
With labbies you have many more ways to control temp. GL -DIY is always best.


Too Many Stickies-- defeats the purpose-

but Bens write-up just got 'bookmarked' by me. Well done.
+1 to you sir.
 
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Benm

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Thanks guys, i plan to do some more writeups on electronics and related subjects in the future - trying to collect some practical knowledge.

As far as the copper vs aluminium issue goes: The only read advantage of the copper is that it has a higehr volumetric energy density. This means it takes longer before you laser overheats, but it also means you have to wait longer for it to cool down. The difference could, for example, be that you get 20s on / 40s off with the aluminium, and 40s on / 80s off with the copper.

The limiting factor is practically always the thermal resistance from the host to ambient, and it will overwhelm all other resitances untill you get something the size of a 2D maglite with fins on it ;)
 
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I wasnt saying that THIS thread was old, I was saying that nobody that has posted in this thread that i created saying something like "omg we went over this with noob X 2 months ago and here is another guy asking the same thing." That is what I meant by old thread. Maybe it is common sense to some people but at it is a true effort to understand something that others consider common sense. I was welding today and once the torch got hot i stopped welding for a couple minutes. Simple enough duty cycle and common sense, if an object you are using has too much of a rise in temperature for you to handle by touch for a certain amount of time then logic would tell you to stop using it. The point i was getting at was to me building and using a laser is slightly different in the sense that in very short time you can destroy a laser diode or components without proper knowladge. Knowing how to determine your duty cycle for a laser seems rather important to me. Now that I have read the posts everyone has left, it seems rather easy to me. Maybe I was thinking too much into it. At least the next person that has the same question i had can use the search menu now and at least see a thread that answers what they are asking for. When i did the search i didnt find anything like this. My feelings arent hurt that you dont want to sticky it and i honestly dont really care. I understand what you're saying about stickies taking up too much space but it could get moved to another page altogether for the newcomers section FOR the noobs! :D But maybe people dont ask this question enough in order to have it stickied...idk

Like i said i dont really care, posting on forums isnt the hobby...building and testing lasers is. I am just clarifying my earlier post and sticking up for myself. Next time i get an idea I suppose I will just consider keeping it to myself, rather than talking about it because after all that is the reason why I joined was to talk about ideas and learn, not be shot down horribly for a thought...

good night
 
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I wasnt saying that THIS thread was old, I was saying that nobody that has posted in this thread that i created saying something like "omg we went over this with noob X 2 months ago and here is another guy asking the same thing." That is what I meant by old thread. Maybe it is common sense to some people but at it is a true effort to understand something that others consider common sense. I was welding today and once the torch got hot i stopped welding for a couple minutes. Simple enough duty cycle and common sense, if an object you are using has too much of a rise in temperature for you to handle by touch for a certain amount of time then logic would tell you to stop using it. The point i was getting at was to me building and using a laser is slightly different in the sense that in very short time you can destroy a laser diode or components without proper knowladge. Knowing how to determine your duty cycle for a laser seems rather important to me. Now that I have read the posts everyone has left, it seems rather easy to me. Maybe I was thinking too much into it. At least the next person that has the same question i had can use the search menu now and at least see a thread that answers what they are asking for. When i did the search i didnt find anything like this. My feelings arent hurt that you dont want to sticky it and i honestly dont really care. I understand what you're saying about stickies taking up too much space but it could get moved to another page altogether for the newcomers section FOR the noobs! :D But maybe people dont ask this question enough in order to have it stickied...idk

Like i said i dont really care, posting on forums isnt the hobby...building and testing lasers is. I am just clarifying my earlier post and sticking up for myself. Next time i get an idea I suppose I will just consider keeping it to myself, rather than talking about it because after all that is the reason why I joined was to talk about ideas and learn, not be shot down horribly for a thought...

good night

My apologies for misunderstanding what you were trying to say...:yabbem:

Exactly... but with Handheld Lasers... you don't wait until they
are too hot to touch... The general unwritten rule would be
when they start to warm up...
:beer:

I'm sorry that we don't post what you want to hear especially
with you being here so long...
You will find that most members will reply/respond to a Post
honestly... It may not be what you may want to hear... but
it is our opinion... That is part of what this Forum is about...

Here's a tissue......:cryyy:

Jerry
 
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My apologies for misunderstanding what you were trying to say...:yabbem:

Exactly... but with Handheld Lasers... you don't wait until they
are too hot to touch... The general unwritten rule would be
when they start to warm up...:beer:

^^^ My thoughts as well. I read your OP so fast I thought you were wanting duty/rest cycle for a 'store-bought' laser. Many China sellers do not tell you the cycling.--Maybe they want to kill it and buy another or maybe they just dont know the correct answer. One I wrote to about this responded== "We sell finest laser, we do not sell cycles'. I think he though I was refering to bicycles ha ha.

One of my rules is-- if you THINK you have been running it too long , then rest it, Thats why I have more than one.

Also if you just go , say 10 or 15 seconds then rest it a few you can pretty much run it all night- just not totally constantly.

Like the guy in the closed 24 hrs resturant told me thru the locked door.

I asked___Hey why are you guys closed? The sign says open 24 hrs??
He sez...
"Yes, we ARE open 24 hrs----- just not in a row"
 
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Its all good guys it was late when i posted that and was overtired and cranky heh but at least things are clarified...

the tissue helped out big time lasersbee, thank you ;)

my parts should be in tomorrow, so hopefully i can get the build started with pics and maybe make modifications to stuff to make it unique.
 
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Its all good guys it was late when i posted that and was overtired and cranky heh but at least things are clarified...

the tissue helped out big time lasersbee, thank you ;)

You are welcome......:crackup::crackup:

Jerry
 




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