Blue laser 74W NUBM35 Portabl?

[RedCowboy]

Looks like you got a good secure mounting to your big heatsink, but your box must be getting heavy, lol.

 

[Borislav@87]

Yes, it's a little heavier, but it's not much of a problem. Even with the current arrangement, the weight is balanced, because in the rear part these 18 batteries weigh. The rear used to feel a lot heavier than the front. It's ok now. Now I have to wait for the new array to arrive and install it. I use terminals to the array instead of soldering. So it can be easily dismantled.

 

[Borislav@87]

Let me add something I noticed. I think the beam divergence could be improved. The front diode I had with broken pins, I had removed the lens with a utility knife. Then when I put it on I put a very thin layer of glue that didn't lift the lens up. The beam was very good and tight until now I see that the factory fitted lens is on a thick layer of glue keeping it away from the laser diodes. Accordingly, the beam is not so concentrated. I don't plan to peel off the lens, but there is definitely an option to improve the divergence

 

[RedCowboy]

When you get your new array mounted and working try putting a normal " strong " glass biconvex lens ( magnifying glass ) in front of it and you can do this to a razor blade, but wear your proper laser safety glasses when you do.

 

[Borislav@87]

Yes yes. If I shine in bright objects, I wear glasses. And what about this lens of mine? Because it's not biconvex, but it works. Also, is it possible for the reflection of the rays that are reflected back to damage the array. Because if the lens is close like mine, the reflection is exactly opposite to the array and the spots are focused, which means they heat up a lot
Even 6 diodes cut a mock-up knife

 

[RedCowboy]

You don't have to put your magnifying lens 1mm away from the arrays gang lens, you can set your magnifying lens 100mm away, it won't make a big difference and at 100mm away the back reflection, which is about 5% for uncoated lenses is spread out, I have never had any issue with it.
This concave lens sits close to the gang lens and the small back reflection is not an issue, also I have used many different lenses close to the gang lens without any problems as each multi mode beam spreads out aggressively, so what actually gets back to each chip is of no consequence.





I also like to make a filter to block the lens glare/flair which cuts down on diffuse light pollution and it helps keep dust and smoke from collection on your lasers lens/gang lens.

 

[Borislav@87]

Yes, I understand that I can put the lens at a further distance. Yours are much thicker than mine from the pictures I see. Well, I'll experiment with time. I'm putting it close because after I slide the new array in, I'm going to close that big gap with a big piece of plywood that I'm going to screw into the front of my case. I'm going to make a hole that is the size of the laser beam so it will block side glare and keep out dust. Kind of like your picture. I had an idea to hold my lens with two magnets for a phone holder in a car. They will be glued to the case, and for the lens I will glue the metal parts


I see you are using the same 600W driver. This driver behaves perfectly. It doesn't even heat up for me at 4A. When I was adjusting the amperage, I saw that when it was turned on, it did not hit 4A directly, but reached 4A in a second. My device first shows low numbers and then reaches 4A. While the other one from 1800W was hitting 3.5A directly. I had kept the piece of plastic from the box. I put it in and pressed it with the lid. It got pretty strong. I also made a hole in the middle.

 

[RedCowboy]

This driver works just fine so far @ 3.5A but I still haven't scoped it, however I do need to use more batteries.
The 4 cells sag hard after 90 seconds and trigger the low voltage protection, but I usually lase for 15 - 45 seconds for which it's been doing just fine.

I haven't spent much time doing anything more than occasionally playing with it as each beam is diverging anisotropically with the fast axis spreading out much more aggressively, what I should do is build my own knife edge array from Sharp 405's or another LD with better divergence, plus I love the deep purple color of 405nm.

What could be fun is to knife edge several of the 7 beam strings so they basically overlap at a maximum useful distance of say... 10 meters and because of how the beams diverge, the knife edged beam bundle would be fun for burning all along it's path, this would be entertaining if the arrays would get inexpensive such as when government/schools replace last years equipment and projectors with 90% life remaining get auctioned off for very little money.

Now the green 525nm array Styropyro used in this video looks to have better divergence and looks to be fairly well aligned, could be a good one to use with a beam expander arrangement, but 500+ dollars for a green light is too much, they should get cheaper when the new ones come out using more efficient diodes and in a smaller footprint like the nubb13

 

[RedCowboy]

Yep, this string of 7 beams @ 3.5A blows holes in this soup can, but it is about 40W so that figures, you can see the reflections off the shiny steel can.
Wear those laser safety glasses !

 

[Borislav@87]

Yes, I am careful. I never shine in glare without glasses. I made a few more changes to my box. I put a fan behind the big radiator blowing directly into it. My goal is not to cool the heatsink, but to cool it down faster by turning off the laser. With this fan, the air in the box will circulate. I already tested it and it works.

 

[RedCowboy]

That's the point of using a finned heat sink, fins add surface area and surface area interacts with air which is a heat vehicle, moving air cools faster and moving air over fins cools even faster.

 

[Borislav@87]

Yes, I am familiar with the principle of operation of finned radiators with active cooling. I'll use it with this one for now. When I put the new array I will see how it is. As a last resort I will put one with active cooling. In my case it will be very easy. I just have to unscrew 2 screws and the radiator is off. I can fit one 13-15cm long, I don't know how many inches that is.

I have this larger radiator on hand. I don't know if it will be enough. I photographed it together with the previous one I used to see the difference

 

[Borislav@87]

At this rate the temperature drops. It drops by 1 degree in about a minute. It's slow, but I don't mind at the moment. I went from 30C to 70C in about 5 minutes of continuous work.

I also put this aluminum radiator and it has an even better result

 

[Borislav@87]

This is after I glued the aluminum heatsink and raised the fan voltage to 18V. There is a marked improvement in the rapidity of the temperature drop

 

[AnselmoFanZero]

I bought a 95W from techhood, they are not really helpful. They added a driver which I am using, the green LED on that thing is lighting up, measured the output real quick, 60V but dropping fast.
Connected the pins as shown, seemed to be the best way to make sure I got short connections and don't have to run wires around the array 4 times.
There is a tiny glow, but I can't even tell if its 2 rows or all 4! Multimeter shows nothing goes through in any direction which is kinda weird. Anyone?

 

[RedCowboy]

What is the part number, is it a Nichia or an Osram because they have a different polarity layout.

If you bought an Osram I am sorry, you bought the crummy one, the Nichias are much better aligned.

Either one will need 95V+ if you connect all 24 diodes in series. 4-4.5V X 24