BTU Shocker Triple MT-G2 with a twist -- Aiming for >100Watt ~9000Lumens -- With external 2S power pack, handle etc...

Thanks M4D M4X!

Just been sent this pic by MRsDNF and I’m pretty excited! Thanks again Steve!

It’s a BTU battery tube machined out to accept 4 18650 cells and it means I’ll also be able to configure this light in a 2s2p 18650 battery configuration for those times when a bulky battery pack isn’t ideal. Awesome :slight_smile:

Small update:

Received the 1uF micro capacitors yesterday so proceeded to slap one onto my frankenstein MCU board and flash it with STAR off time firmware.
Tested the driver last night with the default cap timeout values and the smile on my face was massive, this is what I call a reverse clicky UI! :bigsmile:

Just brilliant! Any thoughts of going for a momentary switch are gone completely.

I also tested the voltage cutoff with default values (128/118) and with my 47k resistor mod the step down seemed to kick in at around 5.35v. Bit low but not bad without any adjustments.
Of course I have to factor in any voltage losses in the cable before the MCU in order to monitor the true battery pack voltage (which can be quite significant at around 0.6v@18A) so this figure should give me an actual battery cutoff voltage closer to 6v.
I’ll probably tweak this to give me a safe cutoff near 6v for using internal 18650 batteries (which don’t see the voltage drop from the cable) and then I’ll just have to accept a higher cutoff when using the battery pack.
Fine by me since I don’t intend to run the lipo packs down that far anyway.

So the driver is ready to be installed. LED wires holes are also drilled so there’s not much stopping me from slapping the whole thing together now. Yay! Expect beam shots soon!

we expect…

Just made this sticker, have a feeling it will be appropriate here… 8)

Steady progress on the internals tonight.

Redesigned the main Battery negative connection on the driver board. Two nuts and a threaded bar now make removing the main connection possible without disturbing the copper post/slave driver at the same time. Want to make sure I can remove these main connections easily to make maintenance and adjustments easier.

I also added some AA and one of those compressible thermal putty pads to each 7135 board before clamping them down. Can’t hurt to keep those 7135s cool. Main heatsinking will be through ground ring soldered to the copper posts however.

Next was building the positive wiring beneath the led shelf, had to make sure this would align properly with the holes in the shelf and fit neatly between the driver assembly and the shelf. Keeping the wiring as thick as possible here to lower resistance loses.

And here is the driver assembly fully sunk into the head. Leaving just enough space to pack a couple coils of 14Awg cabling for the main power and of course the MCU board and it’s own wiring. The BTU driver cavity may seem generous but I’ll be using every last bit of it with this setup. :stuck_out_tongue:

Paramount is that I can easily get to the MCU board and reprogram it even after everything is assembled. Should only be a case of unscrewing the contact board and pulling it out.

And here is the front showing the wires coming through the led shelf.

Looking forward to seeing this running!

Did you plan all this or is it just happening? My head is spinning.

Great work!

Keep going and keep the updates coming. :)

Bit of both :wink:

But to be honest I had a fairly solid idea of how all this was going to go together and it’s mostly going to plan, no nasty surprises yet…touch wood!
If I had a lathe I’d have turned down the back of that aluminum slug holding the drivers a bit. Just to give me a few more mm of breathing space on the rear side of the driver cavity.
But considering it’s just a random part I found in a box it’s actually pretty close.

Here’s the rough 3d plan of the driver setup from a year ago, turned out pretty close. :slight_smile:

Massive image dump incoming!:

Sorry…but I’m pretty pleased with how this is coming together and it’s hard to show how it all works without a bunch of angles :stuck_out_tongue:

The driver assembly is done!
Barring a few last bits of insulating heatshrink this element of the light is ready to roll :bigsmile:

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The MCU board is connected to the rest of the driver and the contact board by three detachable pin connectors.
Black is battery negative/ground, Red is batt positive switched by the clicky switch and Black/Red Stripe is the PWM signal going to the slave drivers.

Contact board, MCU and wiring. Hmm will all this spaghetti really fit in that driver cavity??

All of it should go together something like this. I need the extra length of main power cables to let the assembly twist down while tightening up the center contact board. It’s only a half turn or so at most but important that none of the cables are too short and get in the way. I also want to be able to undo and move the contact board out of the way enough to get access to the MCU later for reporgramming, more on that further down…

These are the main power cables coming from the contact board and the copper contacts that will get bolted to the driver assembly. Small black wire coming off this goes to the MCU ground connection.

And this is how it connects up to the driver assembly. (Still need to properly insulate the positive connection before final assembly)

Here’s another angle showing the wire carrying the switched positive from the clicky switch through the aluminium contact board holder and to the MCU

Not much room to spare! :stuck_out_tongue:

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Just to prove it all works and goes together as it should, here’s a crappy gif showing the assembly process.

And again I want to be able to get to the MCU for easy reprogramming so here is what the in-light reprogramming process would look like.
it’s just a matter of unscrewing the contact board retaining ring, wrangling the power cables out of the way and fishing for the MCU board. :slight_smile:

Job done!
Now…where did I put those Mt-G2s? :wink:

:slight_smile:

Orsm. RBD has your MTG-2 leds. They are with the reflector he last 18 months ago.

I guess I’ve been away too long, who or what is an “RBD”?
And more importantly how do I go about liberating my MT-G2s from such a thing? They’re kind of important to this build…can’t be waiting another year to get this thing finished :stuck_out_tongue:

Actually I wept slightly seeing the newest MT-G2 Q output bins on IO, mine seem rather antiquated in comparison.
Can I get this thing finished before the MT-G3 is announced? :wink:

RBD would be Rufusbduck. He lost from memory a reflector along time ago and its just stuck in my head for some reason so put two an two together rattled it around in my head for a Nano second and came to the above conclusion. I had the same problem when I built my shocker with the MTG-2 led being updated. I wont tell you what I ended up doing. As far as finishing before the MTG bazillion comes out will I suppose depend on how quick the mailman comes.

i cant wait to see it finished…

any new updates? JW if u gonna mass produce a few.

Aha yes of course, the master of looking so sternly at a piece of copper it cringes into an elaborate heatsink. :wink:

Well considering I haven’t even finished the first one, talking of mass production is a bit early methinks. Haha :stuck_out_tongue:
But hey if someone is really serious about wanting a light like this and is realistic about how much it would cost for me to hand make them one. Then sure, I’d be up for building a couple more, why not.
Parts cost alone is over $300 last time I checked, so that should give you some idea.

Oh and Updates are there… I’m afraid you’ll have to look through the thread to see the latest stuff. I can’t update the first post anymore since the thread is so old… :~

I don’t plan on LED/MTG change or Driver change. Just the tactical handle and otterbox & rc batteries. I’ve already gotten a BTU-Shocker. So i thought it would be cheap (under 100). Also thinking of doing a shoulder mount like camcorder’s in the past. A u or clamp mount on an old shoulder pad camcorder pad.

Ah right so you’d be interested in a kit something along the lines of this?

Yeah I could see that working but it does require a modified BTU tailcap or getting a run of custom tailcaps made up. And for the whole thing to thread straight onto a stock BTU, unlike on my light, the handle rail would have to be bolted to the tailcap instead. But in theory yeah that could work fine. A plug and play battery pack kit for BTU owners. :slight_smile:

–2x 3S rc packs in parallel probably around 10,000mah (3s and much lower current requirements from stock BTU would allow for a thinner power cable)
-Main power switched by a Fet in battery carrier driven by clicky in trigger
-MCU in battery pack for automatic overcurrent/undervoltage protection cutoff etc. (still haven’t gotten around to adding this functionality to my pack either but should be relatively trivial)

But for under $100, I’m afraid not.

Quickly worked it out and the cost for just the parts in the image above is over $150!
I’m sure you could source things for a bit less but that’s what it works out for my build, big ticket items such as the battery packs alone will run you around ~60bucks.

yea that’s fine the only big problem would be finding another tailcap without buying the whole thing.