MT-G2 COURUI Anyone? Another O-L mod. PHOTO HEAVY - BEAM SHOTS ARE UP! 02-06-14

02-01-2014

Hello,

What do you get with a COURUI XM-L2 light, an MT-G2 led, a DrJones master w/two slave drivers.... AND

and Six 18350 Efest V2 cells? (I know there's only 4, the other two are shipping to me as we speak)..... AND

and a crazy Old Fart?

You get a torn down mess, is what you get...

Add some copper and it's off the the O-L work shop.

I will be cutting out the center of the threaded Aluminum led shelf and inserting Copper, along with some more Copper under that, so it fits tight in the section of the light that holds it. Just some insurance for the 9+ amps going to the MT-G2 led. Can I get 9+ amps out of 6x18350 2S/3P? Don't know, but I'm going to try...

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02-01-2014 - Evening

So I split some Copper couplings and flattened them. I heat them with a torch, till they turn black when cool and that makes them soft. Flattening is done with a hammer and a block of wood, on the garage floor. I also heated a couple Copper discs, since I will be using at least one of them.

Now, I said that I wanted to make the center of the led shelf Copper. I drilled it out with a 1/2" bit first.

Then I switched to an end mill bit and wallowed it out some more.

When the ID is closer, I switched to a Dremel #115 bit.

Finally, I went with a Dremel Sanding drum, to get the exact dimension I needed.

Now, the 5/8" disc fits in tight. Why 5/8"? Why not 7/8"? Well, that is what I had.

I also want to put a Copper disc on the bottom of that led shelf, so I am cutting around a disc that was close in size, to get it the diameter I need.

After cutting it out, I used a Dremel to smooth out some of the high spots.

Then I finished with rough sandpaper. I am not too concerned about perfect here, because it will be soldered to the center Copper plug and the whole thing needs to screw in/out, so it has to be shy of the thread ID in the light.

Close enough. It falls in.

Screw in the original led shelf and tighten it down.

Now, I need three of the 5/8" discs, so the height is right, so I gob some solder on two of them.

Then I heat and use something, anything, to press down, while it cools, squeezing out the excess solder.

Add a little solder in between and pop the center discs in place.

Use something to press down hard while heating. I also dropped a dab of solder in one of the wire holes, so that I could see when it melted, telling me the center was melted too.

Looks good to me. The MT-G2 on Noctigon will not be soldered on. I will use AA, so it can be easily removed.

Speaking of MT-G2, let's go ahead and open the reflector to fit the led. I just drew a mark on, for a guide and I used my Dremel tool to open up the led hole diameter.

Ouch! That's too big!

See that crap in there? It was almost the end of that reflector. I washed it out, by just spraying Windex in the reflector, followed by plain water. That worked fine, so I used compressed air cans, to dry it out, Just as it was almost done, I shook the can and some of the propellant came out and smeared the top of the reflector! Blue streak here we come!... I tried the Windex deal again, but this stuff was stuck on, so I soaked my hand with Windex and soaked the reflector with Windex and used my finger tip, ever so gently, to clean the gunk off the reflector. No scratches! I do not recommend it, but I have done this before. If you have the reflector soaked well with Windex, and your hand is soaked, the film keeps your finger from leaving a scratch, but you can only rub once or twice and very softy, otherwise, good bye.

Actually, it isn't too big a hole. I plan on having adjustment room, to get the proper focus and so far, all the MT-G2 leds I have done, need to have the reflector base below the die substrate. At least here, I can get the adjustment I want.

Oh, the MT-G2 is also raised on Copper shims, so I have more room to work with reflector height.

Let's go back and add some more copper under the led shelf. The ID here is about 34.10mm and I am cutting out Copper to make a stack of them, to go inside.

These are pipe couplings, so they are thick. I have to use Sheet metal cutters and it's difficult, so I am not trying for a perfect circle. I will just cut an Octagon, to remove most of the excess and then solder them together and shape the whole thing at once.

Kinda like this times 6.

I am reheating them again, before flattening them out again. Working Copper makes it brittle, so after all the cutting I heat them again to soften them.

I just use a big hammer and a piece of wood on concrete, to flatten them.

OK, they are soldered and I have hit the edge with the Dremel tool by hand. Now it's time to start up the drill press again.

I use a block of wood, to keep the piece from flying out the back and I use the #115 bit to shape the circle. A little at a time.

I wanted this one to be really close, so I thought I would use calipers and do some measuring. This is in mm, so you can see I am still about .10mm out of round.

I can mark out the high spots, so I know where to work more material off.

Since I am getting close, I have switched to inches, so I can measure in thousandths.

I have also gone to the drum sander, because I don't have too far to go and I don't want to overshoot.

It's looking better. Here you can see I am down to about .005 out of round and the final sanding for fit, took me down to .003" out of round. Not bad without a lathe.

The edge looks pretty good for a drum sander.

Nice and snug. I am very satisfied with the result. There is no way I can make a huge Copper heat sink, so I just need to make sure the Copper gets out to the Aluminum fast as possible.

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02-02-2014 - Evening

Drivers are wired up. Here the main wires are soldered on the original driver board. I stripped it and am using it as a contact plate.

The three NANJG drivers are all wired and ready to go. This is a Master/Slave setup. The copper strips are "supposed to" help cool the 7135 chips. I am debating on filling the driver pocket with Fujik or not.

Wired to the led and it all works. I tested with two 18650 Li-ion, on the bench.

Another problem I found, is that the original driver plate sits down below the outer lip of the pocket, so the body does not touch the driver outer ring. I made a copper ring to solder to the driver plate. It will be thick enough that the body will screw in and touch it now.

I cut the outside with scissors and used a file, to finish off the outer edge. I scribed where I wanted the inner edge to be.

Then I drilled a starter hole and used the dremel tool to cut out the ID. It's ready to go and I will solder it to the driver.

Another issue is that the two 18350 cells stuck out too far. I dimpled the negative ends of two of the 18350s I have, so I have to make more space for them. Luckily, there's a lot of space in the back, where the rear contact plate could be raised up, so that's what I did.

I gained about 4mm doing this and the batteries fit better now.

I had to re-drill and tap the three holes in the body, to accept longer screws. I used 3mm, because that's what I had.

Then I cut three pieces of brass tubing, to use as spacers and put it all back together.

As far as the reflector focus goes, the tightest spot was with the reflector base as low as I could get it. It is below the led base. It can't go any lower due to wires, but I am glad I raised the led up, or the spot would be very big and not well defined. Every MT-G2 I have played with, needed the reflector to be lower than the base of the led, to get a tighter spot.

Since the reflector is down so far, there is only a little gap when the head is screwed down and it's not enough for me to worry about.

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Not much left now, except for waiting on the batteries and doing beam shots. The lux meter showed 42500 lux at one meter, with the beam focused. That is no better than any 50mm reflector out there, so the bigger diameter reflector is doing nothing for the MT-G2. It will never be a thrower. No MT-G2 will ever be a thrower, but I bet it will be a great light when I get to do beam shots. I prefer beams with a lot of spill and a big center spot, so it will probably be great for that.

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02-06-2014 It Lives!

OK, to correct my previous photo. The back end of the negative plate has the crossover wire on it. It's a little heavier than what was there stock.

The driver assembly is back in place, with the copper outer ring.

The reflector is now polished Aluminum... Yep, I scratched another one! Well, it's still pretty good looking after a lot of 2000 grit wet sanding and #0000 steel wool sanding in water, Plus the dremel with a cloth polisher and Mothers.

Anyhow, the beam shots are up and I got a reading of 8.5 amps on high, with a 1 meter lux of 62,400. Not too shabby I think.

The DrJones driver has two main modes. High and med/low Plus ramping. This is the low setting.

This is High

Low

High

High

100% crop of the lighted area

High

High

100% crop of the lighted area. Along the bank on the right side is a bright spot. That turned out to be a Coyote.

Thanks for doing this, I was contemplating this build or rather one similar. Why not 3 18650s in series? Or are you building a triple MTG2?

Yes, you can definitely get 9A or more out of the 18350s. 8)

The mod to make the 7135-based drivers work with the MTG2 can only handle a max of 8.4v input. 3S/12.6v would require a totally different driver setup, O-L and others use these and live with the limitations because the UI is nice and the parts are already at hand.

subscibed

Awesome!!! I can’t wait to see the finished product!

Looking forward to this ! * gets my cash ready to buy it after *

This is gonna be something different. Not for me at all (MT-G2 does not wow me at all) but it will certainly have something rare and sweet none the less.

I dig it.

I am adding this one to my "must do" builds.

This is going to be ridiculous! Cant wait to see it!

I am using a 6V MT-G2 with NANJG drivers, using the zener mod. I need 2 in series, for the voltage and the 3 sets, (in parallel), of 2 in series, gives me more amperage. 3x18650 in series is just too high a voltage.

EDIT: I coulda just read Post#3 before I made this one.

Even 8 ounces of copper under an MT-G2 at 6.77A is really not enough. 140º on the outside of the head in 5 minutes. And that’s with the copper exposed directly to air, with fins.

9A takes more, lot’s more, not sure if there’s room for enough copper in that light, but it should be fun to play with in bursts.

Updated the OP.

O-L, have you tried Windex (rubbing alcohol works too) on a cotton ball? No scratches. :)

Can’t wait to see the finished product. It should be amazing.

Every time I have used a Cotton ball, it has scratched the reflector. Maybe next time I should not use the ones you pick right off the Cotton plant and use the processed ones instead.

I stopped using Alcohol many, many years ago, but there are still times when feel like I would like to.

I’m clueless, but I sure do appreciate the photos, descriptions, and the time involved in bringing it to the Forum. THANKS!

I always enjoy looking at your process of making copper heatsinks/slugs/inserts. It is always amazing seeing it go from a few pieces of copper pipe to a glorious chunk of heat devouring paraphernalia.

Nice, you made my MT-G2 envy that much stronger…