What Is a good working current for the MTG-2.

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MRsDNF
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What Is a good working current for the MTG-2.

I’m just after members thoughts and experiences on what there recommended current draw and favorite drivers are for this led.

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

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PilotPTK
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3A is already a lot of light. a lot. It will take more, but heat starts to become a real problem. if you can manage heat (really well).. 4 to 5A is very doable.

PPtk

I am currently extremely busy with work. Please do not expect a response from me quickly. I will be dropping in as time permits, but the amount of time I can dedicate to responding to topics and PMs is very limited.

MRsDNF
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Thanks PPtk. The plan is to put it in a Defiant C3 with a similar set up to this one.

 

 

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

ImA4Wheelr
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It will be interesting to hear dthrckt’s input since I think he has driven it the hardest so far. I’m driving at 4+ amp with good heat sinking. It seems to be handling it fine and that it can take more. Using the Manafont “3T6” driver which has the good memory, but blinking modes too. For my app, I want to have the SOS mode available.

Before I got the Sinkpad, I was driving at 3.8+amps and the beam had some blue in it. I’m building a copper pedestal to mount direct on so that I can get the emitter to the right focus in the reflector. Traditional stars will be in the way with this big emitter and a reflector.

EDIT: The above readings are at the emitter using a good DMM that can read up to 20A, but using stock leads. The leads are quite thick, but I figure that the handheld connections and all should be creating some resistance. That is what the “+‘s” above are for.

dthrckt
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If i had your lathe, I’d make a copper pill like the one pictured, but when you face off the surface you’d put the pcb, leave a 6.0mm diameter, 2.0mm high pillar and solder the mtg2 w/ no pcb directly to that. Its big, so soldering the leads directly to the emitter is even easier than an XR-E.

http://www.cree.com/led-components-and-modules/products/xlamp/arrays-dir...

Then use this driver – http://intl-outdoor.com/9a-3mode-5512v-circuit-board-p-561.html

I’m not sure what increase in output to expect (vs the light that I built w/ that driver and mtg2) but I’m quite sure you’ll find the result absolutely stunning…

ImA4Wheelr
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Or, if the pill is already made, you could press in a 1/4 copper round. Even better, 3/8” and machine 2 sides down to 6 mm. That way you get more surface contact. I think the height will depend on your reflector. This is the approach I’m taking because I don’t know the height until I actually see the beam working.

dthrckt
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You’d be ok w/ the sinkpad brand mtg2 pcb and 5A or so at the emitter, but you have to make sure there is very good contact between pill and emitter. If there is poor contact, the dome will bubble at the emitter. If there is (minimally) adequate contact, a light meter will reveal a big sag in output in the first 30 seconds…

One other note about that driver – personally, I wouldn’t consider using it unless it is potted.

anyway, pptk was right, 4-5A is very doable, and w/ great care, so is more

Flomotion
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dthrckt wrote:
You’d be ok w/ the sinkpad brand mtg2 pcb and 5A or so at the emitter, but you have to make sure there is very good contact between pill and emitter. If there is poor contact, the dome will bubble at the emitter. If there is (minimally) adequate contact, a light meter will reveal a big sag in output in the first 30 seconds…

One other note about that driver – personally, I wouldn’t consider using it unless it is potted.

anyway, pptk was right, 4-5A is very doable, and w/ great care, so is more

!{width:80%}https://lh4.googleusercontent.com/-X895_23fhYU/UKGnzuRsesI/AAAAAAAABHg/Q...!

Who has pcb, better, copper pcb for the MT-G2?

Flomotion

dthrckt
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i’m not aware of a copper one, but sinkpad makes aluminum mtg pcbs. maybe someday they’ll get popular enough for a custom run of copper pcbs…

GottaZoom
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ImA4Wheelr wrote:
Or, if the pill is already made, you could press in a 1/4 copper round. Even better, 3/8” and machine 2 sides down to 6 mm. That way you get more surface contact. I think the height will depend on your reflector. This is the approach I’m taking because I don’t know the height until I actually see the beam working.

Or, if the pill is already made you can send it to me and make another like dthrckt suggests. Smile

GottaZoom
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Flomotion wrote:
Who has pcb, better, copper pcb for the MT-G2?

Sinkpad might even send you a couple alum versions as samples . . check MTG2 interest box if you haven’t asked for samples via their website yet.

You can also put copper under “Other”, but that will probably only be XML and XPG versions already available if you check those boxes, too.

ImA4Wheelr
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Quote:
GottaZoom wrote:
ImA4Wheelr wrote:
Or, if the pill is already made, you could press in a 1/4 copper round. Even better, 3/8” and machine 2 sides down to 6 mm. That way you get more surface contact. I think the height will depend on your reflector. This is the approach I’m taking because I don’t know the height until I actually see the beam working.

Or, if the pill is already made you can send it to me and make another like dthrckt suggests. Smile

Damn, wish I would have thought of that one.

comfychair
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1/8" copper plate...

MRsDNF
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Thanks guys for the input If I read this correctly there is no copper sinkpad available for this. Thanks for the suggestions on mounting it on a pillar but with all my electronic skills I would kill the led and I don’t really want to do that with $20.00. So its 5 amps max and lots off luck. Cheers.

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

Hopback
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Would an mtg2 fit on an xre board? Not got one to measure (xre), but looking on the cree data sheets it does look possible…..and you might be able to get a copper sinkpad sample too!

comfychair
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I have a bare Cutter 20mm board and I'll have to desolder an XR-E from a 3-up board, but I can check that fairly quick.

MRsDNF
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comfychair wrote:

I have a bare Cutter 20mm board and I’ll have to desolder an XR-E from a 3-up board, but I can check that fairly quick.

How quick. I’ve got 10 minutes before I go to work? Wink

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

comfychair
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Hell, I don't even need to desolder the XR-E to see that it'll work, holding them next to each other is enough. The MT-G is of course wider, but the spacing of contact-center pad-contact is exactly the same. A little of the MT-G2 will hang off each side but that shouldn't hurt anything.

dthrckt
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It will work, but sinkpad doesn’t make copper XR-E boards (or aluminum XR-E, last time I checked), and if you were going to use an aluminum pcb, you might as well use their MTG pcb, since like all their pcbs, the center pad has no dielectric layer.

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Ooops I didn’t check to see if they did a copper pcb (or not)! Sorry folks

ImA4Wheelr
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I would like to recommend you reconsider your decision to go aluminum star versed direct copper mount. You have build an amazing host that could take the MTG2 to new levels. The aluminum sinkpad will hobble the potential of the light. When you look at this very big emitter, you will see that it would be easy to direct mount on a copper pedestal and then direct solder wires to the emitter.

dthrckt
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I second that, because I think you’re capable, but also for my own curiosity and the good of the forum Smile

There’s a very easy way to reflow that mtg2 onto the pedestal – turn an aluminum ring w/ ID of the diagonal length of the MTG2 and OD that matches the ID of the pill recess. Set everything in place. heat it up. done.

If you want a potted 9A driver I’m happy to do it for you and I already have one ready to go – just tell me the dimension of the driver recess.

GottaZoom
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ImA4Wheelr wrote:
I would like to recommend you reconsider your decision to go aluminum star versed direct copper mount.

This makes it safer and longer lasting, so it is less risk if you use the same amps in.
dthrckt
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and BRIGHTER Party

comfychair
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I do have to warn you though, soldering wires to the LED is HARD once it's attached to a big chunk of copper.

dthrckt
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I’ve done a couple xmls and I soldered the leads first

edit: and if you really want to be safe doing that, use a higher temp solder on the leads…

comfychair
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Really? I figured the heat to reflow would unsolder the wires if they were done first. On the MT-G2 I of course cleaned off and re-tinned the pads before mounting it, it was still a pain (and ugly, I like nice smoothly flowed solder, which this most definitely was not). Silly

dthrckt
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you have to be careful to put the emitter in place right before the heatsink goes below the solder melt temp, then cool it right away…so it can be tricky

but if you used a solder w/ higher melting point for the leads, it should be much easier….

also, w/ the mtg2, there’s enough room to get my 240W soldering gun at those solder points J) , so it might not even be necessary – especially if you do it before the heatsink has completely cooled

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What about drilling the center pad for 5-6mm Dia solid copper. If centered in the heat sink, that could be drilled and soldered too. Or mill the heat sink with a 1.6mm high x 5mm Dia post as part of the sink and drop the pcb over that.

Three Tanna leaves to give him life, nine to give him movement. But what if he eats the whole bag?

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comfychair
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I tried to drill one of the Cutter PCBs to do the copper rod riveting thing and failed miserably. There's a layer of something under the pad that ate every drill bit that even got near it. I dissected it with a diamond file (regular file wouldn't touch it) and it seemed like a layer of ceramic. If so, heat transfer on those things has to be abysmal and just about anything else would be a huge improvement.

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WOW. Talk about put the pressure on. I have a friendly banter going on with OL to push each other that may sound rude to others. But this? I feel humbled by the expectations off members here. This is really pushing my abilities. Thanks to members here my soldering has improved 10,000 percent but in others eyes is still horrible. The offer off nine amp drivers potted that I marvel at is very generous (I cant think off the right words). Thanks. Rufusbduck I like your thinking as I dont have access to a mill but could possibly do what you have suggested. If you all knew my reputation for wrecking electrical components you would understand my hesitation. I have the led and it cost 20 bucks. Do I risk trashing it with my none electrical abilities and drive it at nine amps? I have a five amp driver ready to go. The host is on its way from the good old USA. Decisions.

Thanks for all the input guys. I have just taken a couple off Bex and heading off for a Nanna nap. Smile

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

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