Pman's NUBM44 build plus comparison shots

[Pman]

So, I had put off building a 44 because I already have so many blues in that wavelength and was hoping that a 10W diode would appear. Had one last MX900 with sink and enough $ in my paypal to cover the cost so I gave in as I also haven't seen or heard talk of any hotter diodes yet. Here's the 7W SXD-V3 4.5A build:

Started out I have a screw together sink as in the type where the diode sits into a groove of the front hald and then the back half screws down against the back side of the diode for cooling. Like a previous build I had decided because of how much room there is in the MX900 and the size of the sink to add some extra sink material with whatever I could come with that I had on hand. This resulted in a bunch of copper washers being thermal epoxied together under pressure and then using thermal epoxy again to the sink with pressure to make good contact with it. You can also see the SXD-V3 driver has a nice thick copper sink on it also:

General pic of the parts and then with the host changed to blue accents with blue electrical tape found at Harbor Freight in a 5 roll pack on clearance:
http://imagizer.imageshack.us/v2/800x600q90/923/kc7gAk.jpg[/IMG

[IMG]http://imagizer.imageshack.us/v2/800x600q90/922/DGdg0K.jpg]

I also found a coupling that I cut down that created another outer ring around the washers and added that too:

What I'm showing here is a large copper fender washer and another stack of 3 more copper washers that I am going to add after I install the driver. I was doing parts of the build while awaiting the diodes arrival:

Now there is a reason why I have that fender washer. On all the screw down back half sinks I have seen the front of the diode sits into a shallow groove for the front section and there's a significant portion that ends up sticking up. When you screw down the back half of the sink so that it presses up against the back half of the diode you end up with an air gap all the way between the 2 sink halves. What I did was take an 8mm thick washer and basically sand it down to 4mm so that it is just a teeny tiny bit lower than the diode so that when I use thermal epoxy on both sides of the washer the gap will be covered and there will be better overall heat transfer between both sides of the sink:

I used MX4 carbon based thermal grease just in case there was any chance of it getting on the pins of the diode:

Diode arrived so it's wired up and ready to be installed:

All I'm really showing is that I used the non-conductive MX-4 on the back side of the diode also. This diode is harvested and the back side isn't perfectly flat and that's another reason for the thermal grease:

I was going to use those King Kong cells but my new 26650 25/50A cells arrived so I'm going with those instead. The sink halves are locked down very tight to each other with large wrenches:

Driver wired:

Not sure how I missed a picture of it but the drivers copper sink is just slightly longer than the driver on the half facing the diode on purpose so I could thermal epoxy it to the inner set of copper washers. I then epoxied the final 3 set of larger washers for the most sinking and wired it to the host:

Completed laser pics:

 

[Pman]

So here's a few beam shots alone with a 3 element:

A few outside shots against my front tree. Can you see anything a bit stinky about these pics?

Say hello to my little friend:

Took a daylight shot. You can just see the beam but it's not like it's in the sun and it's missing a third of its output because of the 3 element:

Tried to do some comparison shots. This is the lineup from 445-473nm+ from my wife and I trying to set them up in the order of wavelength with our eyes. The problem is there is too much of a difference with some of the output powers which confuses things as brighter looks like a higher wavelength when it might not actually be. Interesting to see where they fit in in comparison with the next set of shots coming up:

I changed the order around to still keeping the same wavelengths/diodes together from 445-473nm+ but now they are in order of power output. It just means that wavelength is first but within that wavelength they are in order of lowest to highest output. They are all using 3 element lenses so they are also all down on power by about a 3rd:

This is the second time in a row I've accidentally left some lights on in the family room. The house is a 4 level split and I'm obviously taking the pics in the basement.

 

[ElectricPlasma]

Wow, that's a ton of light. I would probably crap myself if I was going to operate that many lasers at once Amazing shots though.

 

[Mattronium]

Another very nice build man. I'm surprised there weren't any flames in the pictures with all of the lasers going

What is the run time on a larger host like this.
Even for a large heatsink, that is a lot of power to dissipate.

 

[GSS]

Just love the way you put as much heat sinking as possible:beer:
Like Mat asked how warm did that host get?

 

[Pman]

I didn't actually check to see how warm it is. It's an interesting question though that I have been pondering for some time. It seems most people assign some arbitrary number to their units so if someone has the magic formula for figuring it out I only guess like others.
I have at least 10 ways to measure the temperature accurately by contact or infrared though. Maybe Red can answer this one for us as he pushes his stuff sometimes to literal death. Have a lot of respect for that to be honest as I'm so conservative with them. Lately I've been taking risks though

 

[GSS]

I see 15 upper level class 4 lasers on at the same time No way they were run less than 2 minutes before you got to take one pic. I would say that extra sinking is working quite nice
Yup Pman, I would say lately your living on the edge

 

[RedCowboy]

Good looking build Pman. :gj: I like how you connected the body into the heat sink at both ends, the 44 makes a lot of heat.

I would expect your heat sink will be plenty warm in 60-90 seconds because the NUBM44 running at 4.5 amps will near 5 volts, be sure to touch the front of the sink as well as the body when judging temp, of course you know this.

Actually here's a pic and some math.

In DTR's pic we see 4.5 amps and 4.7 volts so the diode is getting 21.15 watts and putting out lets call it 6.9 watt, plus the lens is eating a little but the math works out the same. So there is 14.25 watts of heat going into the heatsink.

So to visualize, it's like pointing 2 running NUBM44 lasers just like it at the flashlights head and let it cook for 60 seconds.

My massive bowling pin size builds get pretty warm in 5 minutes, but take 8 minutes in the winter when used outside, and 3 x 26650's of good quality IMR formulation will carry it, 2 x 26650's will carry it for many minutes until the sag gets below the drivers cutoff, 6.8 volts for the SXD that is a good driver.

For 2 x 26650 cells with the 4.5 SXD I charge when they get down to about 3.35 volts each. Powering the 44 at 4.5a the SXD takes 2 amps at 12v and 3 amps at 8v , basically 24 watts in how ever it has to get it.

We do slowly lose output at these higher drive levels, there comes a point where the waste heat can not get away from the diode as fast as it's created, the factory spec will run all day with active cooling, but the bigger your heat sink and the more surface area to move heat into the air the slower the power drops due to heat build up, our heatsinks are heat reservoirs without surface area multipliers such as fins and active cooling such as a fan that is used in the factory devices.

Also diodes are less efficient the harder we drive them, the short story is for a fun burning laser built to work hard go BIG on the heatsink, you can see this in DTR's videos here.

I like the build Pman, you will enjoy the power, you can add a sanwu 3X expander for longer reach or use a G2 as is for more punch at desktop. Also if burning at desktop a G2 saves on waste heat build up and lets more power through. :beer:

These are DTR's videos: YOU CAN VIEW BOTH AT THE SAME TIME.

This is with a 3 element.



Here's a 3 element with more heatsink and surface area.

I have seen him testing before and back the power down to factory spec plus a bit and the output will actually start climbing in the heavy heat sink because it is dissipating heat as fast as it is making it. The ferrous diode backing may be a bottleneck beyond factory spec, the projectors turn up the current slowly over the diodes lifespan, that's one reason we have so much headroom, and why we saw 9mm replace 5.6mm DTR's FULL COPPER modules pull heat from the sides and back, and a dab of compound in there helps, theoretically the diode reaches a point of unity where it sheds heat as fast as it makes it at factory spec, but for us power pushers the bigger full copper modules 20, 25, 35mm sound like a good way forward barring active cooling. I like a big heat sink.

I get mine pretty darn warm, but not too hot to hold, the 44 is a tough diode.

Enjoy the power Pman.

 

[Pman]

Those are interesting videos. I only ran mine with a G for a moment to check it and would only use a G if I was going to mess around investigating the burning ability which I am tempted to do.
Yes it would be better to run 3 26650 rather than 2. Would be interesting to compare a 3 cell arrangement that would equal the length of 2 26650 but I don't know of anything that would be the correct size. What really gets me is why there is not a much larger difference in capacity as the cells get larger as the surface area of the cells should give more capacity than they do in my opinion. What are they doing with the extra space?
I have been thinking about that debris issue that has caused issues as we go up in power and am thinking a very likely cause is not getting the grooves on the lens and module totally clean. Only takes a spec to cause an issue. Keeping an eye out for any change in spot.
Would like to see others input on the magic number used for heat sink temperature/diode for figuring out a proper duty cycle. Everyone wants to know what the duty cycle is when they buy a laser so how did you sellers come up with the numbers? It was getting warm or hot to the touch doesn't sound like a very accurate way to come up with the recommendation to me

 

[Cel]

Lovely beamshots, the beams look like some magical strings or ghostly wires of a harp.

 

[RedCowboy]

Those are interesting videos. I only ran mine with a G for a moment to check it and would only use a G if I was going to mess around investigating the burning ability which I am tempted to do.
Yes it would be better to run 3 26650 rather than 2. Would be interesting to compare a 3 cell arrangement that would equal the length of 2 26650 but I don't know of anything that would be the correct size. What really gets me is why there is not a much larger difference in capacity as the cells get larger as the surface area of the cells should give more capacity than they do in my opinion. What are they doing with the extra space?
I have been thinking about that debris issue that has caused issues as we go up in power and am thinking a very likely cause is not getting the grooves on the lens and module totally clean. Only takes a spec to cause an issue. Keeping an eye out for any change in spot.
Would like to see others input on the magic number used for heat sink temperature/diode for figuring out a proper duty cycle. Everyone wants to know what the duty cycle is when they buy a laser so how did you sellers come up with the numbers? It was getting warm or hot to the touch doesn't sound like a very accurate way to come up with the recommendation to me

The mAh can be a lot higher, but our low resistance INR/IMR formulated cells that give a high discharge with minimal sag trade off capacity for high drain low sag.

An 8000mAh cell would run a puny flashlight much longer than a 4200mAh high drain low resistance cell, but that 8000mAh cell would sag terrible if asked/loaded to put out high current.

 

[Sta]

Re: GUIDE: Which company should I buy from?

Those are interesting videos. I only ran mine with a G for a moment to check it and would only use a G if I was going to mess around investigating the burning ability which I am tempted to do.
Yes it would be better to run 3 26650 rather than 2. Would be interesting to compare a 3 cell arrangement that would equal the length of 2 26650 but I don't know of anything that would be the correct size. What really gets me is why there is not a much larger difference in capacity as the cells get larger as the surface area of the cells should give more capacity than they do in my opinion. What are they doing with the extra space?
I have been thinking about that debris issue that has caused issues as we go up in power and am thinking a very likely cause is not getting the grooves on the lens and module totally clean. Only takes a spec to cause an issue. Keeping an eye out for any change in spot.
Would like to see others input on the magic number used for heat sink temperature/diode for figuring out a proper duty cycle. Everyone wants to know what the duty cycle is when they buy a laser so how did you sellers come up with the numbers? It was getting warm or hot to the touch doesn't sound like a very accurate way to come up with the recommendation to me

Regarding the difference in capacity - most of the li ion battery industry's efforts have gone into 18650s, since they are more common. The other battery sizes have not really been modernized yet.

 

[RedCowboy]

The sub ohm vape market has pushed 18650 and 26650 ahead of the rest, IMR/INR are pretty tough, but I am ready for what's next, do you know of an 18650 that can beat a BASEN 26650 IMR, I hold 4.0 volts from a 4.17 float into 1 ohm pulling 4.0 amps for 30 seconds before dipping below 4.0 volts, the best of my 18650's can't do any better and don't last as long. The Basen are 5000mAh and 50amp cont with 60amp pulse.

My 18650 Panasonic can't compete and my LG INR can't hold up as long, they are 4000 mAh

I work my NUBM44's like a maniac and burn for 5 minutes at a time, so far the IMR 26650's last the longest.

 

[Sta]

The sub ohm vape market has pushed 18650 and 26650 ahead of the rest, IMR/INR are pretty tough, but I am ready for what's next, do you know of an 18650 that can beat a BASEN 26650 IMR, I hold 4.0 volts from a 4.17 float into 1 ohm pulling 4.0 amps, the best of my 18650's can't do any better and don't last as long. The Basen are 5000mAh and 50amp cont with 60amp pulse.

My 18650 Panasonic can't compete and my LG INR can't hold up as long, they are 4000 mAh

Pretty sure that the Basen can't go to 50amp. That's what they say but after looking at some tests from lygte-info.dk it has become pretty clear that 26650 current ratings are never true.

 

[RedCowboy]

What's the toughest 18650 that can carry 12 watts continuous output?

 

[ElectricPlasma]

I'm inclined to agree with Sta, I strongly doubt that two small batteries can out-do a car battery in terms of current draw. 50A is just a sh!t ton of power to be coming from it.