Cheap DIY Heat Sink for Ophir 20C

[ScottW]

I recently purchased an LPM with an Ophir 20c head. The meter is capable of 7W, but Ophir recommends additional heat sinking be added to the head before measuring >4W. Now I know mrcrouse makes some beautiful heat sinks for the Ophir 20c, but my wallet was still crying (and empty) from the LPM purchase.

So I decided to try the DIY approach. A quick search turned up this extruded, finned aluminum heat sink on Amazon for about $6 with shipping (now about $7):

Nobody will ever mistake me for a machinist, but I do own a hack saw, vise, some files, and a drill. So I proceeded to:

1. Cut the extrusion lengthwise between the 5th and 6th fins, making it 29mm wide.
2. Cut the remainder into two 37mm lengths.
3. Clean up the hack-sawn cuts with a flat file.
4. Mark, drill, and countersink two 5mm holes in each, between the 2nd and 34d fins, for mounting screws.
5. Spray all but the contact surfaces with some Krylon satin black engine paint leftover from a car repair.

All of that, and some time for the paint to dry, got me to this point:

The final step was mounting them on the Ophir head. For that, I used (4) M4-0.70 x 25mm stainless screws and washers from the hardware store ($1.55), and a little Ceramique2 compound leftover from a 9mm build.

So for about $8 and some leftovers from other projects, I am quite pleased with the result. Bring on those 4W diodes!

 

[crazyspaz]

Nice cheap approach- doesn't look bad at all, either!

Nice cheap diy heatsink! looks best for a dpss.

best for a dpss...? What are you talking about, you seem to like posting random things...

 

[BowtieGuy]

Nice looking DIY solution, almost looks as if it was made for it.
Now bring on those monster diodes!

P.S. - Damn, just looked at my post count, 666 sh!t

 

[ScottW]

Nice looking DIY solution, almost looks as if it was made for it.
Now bring on those monster diodes!

I'm ready! Or at least the Ophir is. I believe I have added enough heat sinking here to get the Ophir to its full 20W potential. Of course I will need a new meter to go beyond 7W, but realistically that is a while off. (I'm actually not sure I would ever want a laser over 5W, as the precautions needed to avoid damage are just too great.)

There is a great article on Ophir's web site about heat sinking the 20C. They recommend a heat sink with "roughly 120 square cm at least" in order to measure 20W. The two finned sinks I added have about 160 square cm of surface area (those fins add up fast!), so I think I'm covered.

P.S. - Damn, just looked at my post count, 666 sh!t

Yikes! Post again quick!

 

[BowtieGuy]

Scott, it looks like you've got the heatsinking problem more than covered, according to Ophir. :beer:
I put one of those mrcrouse heatsinks on mine, but I haven't had the opportunity to put it to the test with anything more than my 2.8 W 445.

Whew! .....with this post, I am now out of the reach of the devil!

 

[ScottW]

I put one of those mrcrouse heatsinks on mine, but I haven't had the opportunity to put it to the test with anything more than my 2.8 W 445.

I saw that in my searching -- you posted some nice photos of that and it looks great (especially with the black anodizing). And I *almost* sent a note to Mike telling him "I want a heat sink just like you made for BowtieGuy". :beer:

Whew! .....with this post, I am now out of the reach of the devil!

Apocalypse averted! :evil:

 

[Hikke]

 

[Benm]

Nice heatsinking upgrade

I suppose you painted them black just for aesthetical purposes though right? A paint can be black in the visible spectrum, but what's important here is the emissivity in the far infrafred. I'm not sure about this specific product (i guess it's the heat resistant spray paint), but results may be surprising.

The other extreme of this is white radiator paint, that's pretty white in the visible spectrum but actually pitch black down the IR spectrum so it makes your radiators in your house more efficient.

 

[paul1598419]

You know this is a 4 1/2 year old thread?! I would much rather new members start a new thread than post their wares for sale on these old threads.