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Will this aluminum heatsink be enough?






Sta

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If it's only 2W, it should be fine, but be careful not to run it for too long. I'd suggest stopping at 60 seconds.
 

Pluxx

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If it's only 2W, it should be fine, but be careful not to run it for too long. I'd suggest stopping at 60 seconds.
Can i use it for longer if i use thermal paste??
 

gozert

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No, thermal paste will likely not do anything to increase your duty cycle. It makes the heat transfer better, but the heatsink can still only dissipate a certain amount of heat regardless of the thermal paste. If you want better duty cycles then I'd recommend you to search for a host with a larger heatsink. You're also going to want to heatsink the driver at some point.
 
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Pluxx

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No, thermal paste will likely not do anything to increase your duty cycle. It makes the heat transfer better, but the heatsink can still only dissipate a certain amount of heat regardless of the thermal paste. If you want better duty cycles then I'd recommend you to search for a host with a larger heatsink. You're also going to want to heatsink the driver at some point.

I bought the driver from survival laser on their website its stated that due to high efficiency of the driver no heat sinking is required is this true??

I have mine set to 1.5A if it helps

Here's a link as well:

Survival Laser Driver
 
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Hi,
Personaly i would have went with Copper sink. The M140 you can possibly get over 2W's if it;s efficient . Even with you running at 1.5A duty times are shortened just iike Gozert implied. So just be careful there will be other builds. kudos to you great job.

Rich:)
 

Benm

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That only means the -driver- does not need a heatsink and makes no difference to what the laser diode requires at all.

As for that heatsink and others like it: for continous operation they aren't all that good, they just provide a thermal connection from laser diode/module to host, and what happens beyond that is basically anyones guess.

The heatsink itself is not really at fault there, it is the thermal resistance from host to ambient that becomes the limiting factor.

It is something you should probably measure though, perhaps the C6 host is large enough to ditch the heat produced by the diode if properly coupled.

Also i don't consider any laser pointer that has a duty cycle limit to be well constructed - it ether works from full battereies all the way down in one go, or thermal design is a fail.
 
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It will get warm fast, 30 seconds. It's really not enough for my taste and if you don't have good thermal transfer with your housing then it will only be good for 1/2 min on 2 min off.

I think it's too puny.
 
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I have the exact same laser, with the exact same diode/module, lens, 1.5A driver, C6 host, the only difference with mine is that I used the copper heat sink of the same size. It meters at 1.5W with the 3 element lens and has a duty cycle of approximately 40 seconds, so with the cheaper black aluminum I would guess 30 seconds on 1+ minute off.

The C6 is a very small host, anyone who has never seen one in person can look at my build here: http://laserpointerforums.com/f65/assembled-m140-c6-pic-heavy-83543.html if you scroll down near the end of the first post there are 4 photos next to other objects to show its small size.

Alan
 
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Hi,
So what PI is saying is the C6 will do better overall with a copper sink even though the host is still small to take the transfer to it. To the point Thanks PI..

Rich
 

Pluxx

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I have the exact same laser, with the exact same diode/module, lens, 1.5A driver, C6 host, the only difference with mine is that I used the copper heat sink of the same size. It meters at 1.5W with the 3 element lens and has a duty cycle of approximately 40 seconds, so with the cheaper black aluminum I would guess 30 seconds on 1+ minute off.

The C6 is a very small host, anyone who has never seen one in person can look at my build here: http://laserpointerforums.com/f65/assembled-m140-c6-pic-heavy-83543.html if you scroll down near the end of the first post there are 4 photos next to other objects to show its small size.

Alan

Well i've decided to get this host instead DIY Stainless Steel Host Assembly, Extended Heat Sink, Unmarked

Will this one be enough for continuous operation? Also i got a small aluminium heatsink for the driver just in case since 1 dollar dint make too much of a difference.
 
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Well i've decided to get this host instead DIY Stainless Steel Host Assembly, Extended Heat Sink, Unmarked

Will this one be enough for continuous operation? Also i got a small aluminium heatsink for the driver just in case since 1 dollar dint make too much of a difference.

I would expect a duty cycle of 60 - 70 seconds, not sure exactly. I also have that same host but with the extended and tapered copper heat sink with a 445nm diode twice as powerful, 3W or a little more, and I consider the duty cycle to be 35 seconds, so with the M140 probably twice that.

Be sure you spend the extra $1 for the drilled pill or you won't have room for your wires. The extended heat sink is longer and makes contact with the pill.

That 1.5A driver does not need a heat sink.

Alan
 

Pluxx

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I would expect a duty cycle of 60 - 70 seconds, not sure exactly. I also have that same host but with the extended and tapered copper heat sink with a 445nm diode twice as powerful, 3W or a little more, and I consider the duty cycle to be 35 seconds, so with the M140 probably twice that.

Be sure you spend the extra $1 for the drilled pill or you won't have room for your wires. The extended heat sink is longer and makes contact with the pill.

That 1.5A driver does not need a heat sink.

Alan

Ok now i undersatnd thanks a lot for the help. Just one more question, how long should the laser be off after the 70 sec mark?
 
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Ok now i undersatnd thanks a lot for the help. Just one more question, how long should the laser be off after the 70 sec mark?

It depends on the air temp.
If it's winter time and windy it will cool faster, if it's summer and the air is still it will cool slowly.
Basically you go by feel.
If from a cold start you go from 70 F to 105 F and that takes 35 seconds then if you only let it cool to 88 F you will not get 35 seconds until it's 105 again.

A large heat sink with fins will give you the best air cooling.
Fins multiply surface area as each fin is a heat vehicle.

Otherwise larger heavier heat sinks give you more run time until it is warm.
But the more surface area the faster the heat can transfer to the air and the longer your duty cycle will be.
The better hosts are aluminum and/or copper and the entire body acts as the heat sink, such as the ones below.
p.s. Stainless steel is slow to move heat and not as good as aluminum or copper.


These are a great value for your money and the larger ones will let you have more fun before cool down time.
http://budgetbeams.com/index.php?main_page=index&cPath=18&zenid=41cb4ce72c9b5258883aead5190d0826

Everyone seems to love these and the prices are not much more, the bodies act as part of the heat sink and they are a great choice.
http://laserpointerforums.com/f39/fs-custom-laser-hosts-new-hosts-added-today-9-2-15-a-93207.html
 
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Ok now i undersatnd thanks a lot for the help. Just one more question, how long should the laser be off after the 70 sec mark?

I would give it 2 minutes usually unless you're outside in the winter time.

Alan
 

GSS

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A little off the cuff, but would putting a laser in front of a fan after use cool it down any quicker and would it cause some damage from not letting it cool the way its supposed to?
 




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