heatsinks?

[iroquois]

What kind of heatsinks would you guys recommend for a knife edge array setup for a long duty cycle?
For 12mm modules I found this design:
http://i.ebayimg.com/00/s/MTA2NlgxNjAw/z/JpcAAOSwyZ5UmQRv/$_57.JPG
But its not easy to attach a fan to it when needed.

There's also this design, and it has screws on the back for screwing a fan, but I only found 13mm of these, no 12.
http://i.ebayimg.com/00/s/MTA2NlgxNjAw/z/HcMAAOSwAL9UkViJ/$_57.JPG

 

[blasterman]

I can't stand cylinder / screw style heat sinks because variations in machining inhibit proper thermal transfer. Visualize a cylinder sitting inside a smaller cylinder and how much contact is being made. If it's machined tight it will be OK. If it's not machined within tight tolerances you will have a gap of air around the diode jacket/module, and that's not good. All the screw does is press the diode module to the side of the inside. Stupid, right?

For anything above 500mw and long duty cycles required I *only* use the black Z-bolt sinks because they clamp around the entire diode module.

 

[iroquois]

Thanks a lot for the info mate
The second image I posted seems to be like the one you linked to ( http://i.ebayimg.com/00/s/MTA2NlgxNjAw/z/HcMAAOSwAL9UkViJ/$_57.JPG ) and it has screws in the back to attach a fan, like the commercial 50-200mW laser modules I've seen inside my projectors.

Although it appears to have threads in the front and maybe it's not made to hold a 12mm laser module inside ( https://sites.google.com/site/dtrlpf/_/rsrc/1344530541708/home/diode-modules/P10194931.jpg ), but just the diode and the front screws are for attaching lenses ( http://img706.imageshack.us/img706/3262/p1017431.jpg )?

I'm new to heatsinks, is it a good idea to cover the sides of a laser diode with thermal compound/grease before putting it in such a heatsink to increase contact area?

 

[blasterman]

Many of my projectors use the same kind of heat sink with those mini fans on the back. They seem to work ok up to about half a watt. Then again I had a 500mw Mitsi 638 die after about 50 hours in one of the gold colored heat sinks you see from the same vendors because it didn't have snug enough contact. Again, all the contact screw does is press the diode module against the side. For anything over half a watt and I want it to last I'll stick to the Z-bolt sinks because they make solid contact around the entire module. If I had my own lathe I could obviously make a hole to my own standards.

Lithium grease isn't a bad idea for permanent mountings. However, thermal grease compliments a good heat sink interface. It won't help a bad one (too much gap).

 

[iroquois]

Thanks for the info again.

For anything over half a watt and I want it to last I'll stick to the Z-bolt sinks because they make solid contact around the entire module.

I think I'm struggling to understand what the "Z-bolt" sink is and how its different (from the blue one, not the gold one)

So for over a Watt of diode you use a specific type of heatsink with a fan? or something else as well? And what's the duty cycle you get? (I know it depends on the diode, Watts, I'd just like an example with some diode). Fail to find this kind of info anywhere.

And is the laser module really necessary if you're going to use a heatsink and move the driver outside of the module anyway? Are there some laser heatsinks that you can just attach the diode and screw the lens into directly (the blue one I linked to seems to have threads in the front which I'm guessing might be for lenses.

 

[Ehgemus]

If you need any special heatsinks built let me know maybe I can help you.

This Heatsink is a Direct press diode heatsink but they can also be made for 12mm modules.