Quarantine Project DONE!

Thanks! I’m excited. Right now waiting on parts from China for major work to move forward. The biggest issue with getting it right is the reflector for the throw. I priced one for like for the MF04 and it’s $125 :zipper_mouth_face: the GT reflectors are about the same and Lumintop is the one making them. I’ll make it work though. Just won’t throw as far as the GT.

Nice project :+1: Good luck with getting the right reflector :beer:

Here's some work I did tonight for a few hours. I ran into some issues...

First was wiring the driver to the emitter through the heatsink. I planned on drilling holes through the copper part, but that would have caused clearance issues with the bottom of the reflector because I'm using 18 gauge wires. So I'm using some insulted solder tabs from some (what were probably really expensive) industrial tablet PC battery packs that were hiding in a box of computer junk I got from a guy on Craigslist. I stripped off the insulation and soldered them to the MCPCB and wires from the driver.

In the process, I managed to rip off the battery negative solder pads so I had to switch things around. That's why the LED is positioned differently in the other photos.

Done! Now on to the part I was dreading. Wiring up the driver. This took about an hour of positioning wires, trimming, and rearranging things to get it to work...

Nope! Backwards!

The right way...My fingers got burned quite a bit holding wires while soldering them into place without bridging pads or connections.

It's a tight fit, but there's enough clearance for the wires. I did put a strip of electrical tape on the bottom of the heatsink for extra protection against shorts. The wires pass up through the fins in the heatsink to the tabs that go to the MCPCB.

Done! Well at least this part. Still a long ways to go.

I mocked it up and tested everything. It works fine! That white switch is the one that came in the host. Looks like an Omten 1288 clone or something. It's really sturdy and has a super nice clicking action, nice and precise (reverse clicky). It's meant for 4.5v and about 350 or 400ma to the incandescent lamp. I'll be putting close to 6 amps through it about 60 watts or so. So far it survived some testing really well.

Tomorrow, I'll build the battery pack as I got a special delivery Wednesday!

Today was time to do the battery. As I said, I'm using 4S2P made of Sony (actually Murata) VTC6's. I got these from Lithium Ion Wholesale for a decent price, but still not cheap! At least I know they're real and not fakes. That's the most expensive part of this whole deal since everything else is around $5 to $12.

Time to disrobe the old battery. I will be re using the BMS board and balance plug. Kind of bittersweet since this was the 2nd battery I ever built in 2017 I think for the 100W flashlight as an upgrade from the 3S2P original. It's made up of green Samsung 22F and I think LG salmon colored ones of the same capacity laptop pulls. A couple of the series cells and probably a parallel one got damaged from the 10 amp input required by that flashlight and started to read under 3.5v while the others read over 3.8. I built a 5S battery for it.

Naked! You can see some of the connections for the BMS. The balance plug sticks out the back. The blue wire is the 2S, and the red wire is the battery+ (14.8v) and the black wire is battery- (gnd). On the other side is the 3S and 1S connections.

The BMS board. 15A continuous rating and it does have reverse polarity protection unlike a lot of Chinese electronics. I got it for around $5 on eBay. On the bottom you can see the connections for the balance leads. The charging input is on the bottom oddly.

The only thing I like more than my soldering iron is my hot glue gun Laying out the cells for series/parallel configuration. I use tape to hold them together before gluing. The battery + is on the bottom left, and battery- is on the top left. The 2S is on the right side. It has an extended tab for the balance connection.

Joining the batteries. Disclaimer: I don't recommend soldering. To do it right, get a spot welder made for this. You risk overheating your batteries and damaging them (over 60C to 100C is fatal to a li-ion battery), or worse, you might get a thermal runaway, which is bad. I do it this way because a spot welder is like $250 even for a cheapish decent one that won't kill you, burn your house down, or die after 30 minutes. I use a 72W soldering iron (crank it up to 350C), high quality .032 63/37 sn/pb solder (Kester 44 eutectic) and am very careful. I let the batteries cool down between each connection and make sure they don't get hot. I even use a paper napkin soaked with rubbing alcohol to cool them off if needed. I scuff the contacts with 500 grit sandpaper for a better surface to solder on.

I make the tabs from pure nickle strips. I got a 10 ft. roll of it from eBay. 8mm wide by .15mm thick. You have to get pure nickle since it solders really nice, is ductile/flexible, corrosion proof, and holds up under high current better than steel or plated steel. I drill holes where I solder to the battery contacts. It drastically cuts down on the amount of time the heat is on the battery and it's easier to get strong joints without putting a lot of heat in the battery.

Tin the contacts of the batteries and let them cool a bit before doing the connections. Be quick! Only keep the heat on enough to wet the solder. I tin the battery-side of the strips as well.

Battery output side, B+ on the top, B- on the bottom.

Other side finished with the 1S and 3S contacts. 3S is on top, 1S on bottom.

All finished! I checked the voltages at the terminals to make sure it was all correct before soldering the connections to the BMS board.Put it on the charger to verify no shorts or bad hookups. Looks good. Charges fine.

I put electrical tape and then masking tape over areas that might short. It will me semi-permanently mounted in the host. The charging leads are exiting the left side of the BMS. Those will go to a barrel jack for charging. The balance port and charging port will come out the back of the flashlight body. The battery outputs aren't on yet because I haven't figured out how to connect them to everything yet. Next was supposed to be figuring out the reflector, but I ruined it earlier because I melted it and hogging out the melted part was a fail so I'll get another one from a donor light. I won't be fiddling with it until my spacer/centering rings get here from China sometime the first week in May (I hope) though since the edges of the die touched and melted the reflector. I decided to do the fan mounting, but the fan I got was also too big. I need a 70mm, not 80mm. Hurry up and wait...Say tuned.

I did some more work the last 2 days. While I'm waiting on parts from China, I decided to mod the host a bit for the battery pack. Time to cut openings for the charging port and balance socket. I decided to keep the cutouts attached to act like covers for the openings for water resistance. I made a template as a guide and used a really thin, crazy sharp razor blade to cut these out. First the balance port.

Then the charging port. It's a barrel jack.

You can see how it looks when done. I will add some cut outs to make it easier to open the flaps, and glue raised rubber seals that cover the openings to the ports later.

Time to figure out the electrical connections for the LED and fan (it arrived Wednesday-I bought it from a US seller).

The white JST-HX connectors are for the fan. I actually used the fan's connector leads and ditched the 3-pin connector that connects to a motherboard. The fan leads just slid into the JST connector and I added some heat shrink insulation and glued them in place. Works awesome. The Molex connectors are donors-I will be using the metal connectors inside.

Fan connector done! Now to the driver connection. The switch is the one that came with the host and has a nice holder for it, which makes it easy to take in and out.

The Molex connectors are removed from the plastic plugs ready for soldering.

Done. You can see how it all fits together. I soldered the ground connection to the driver holder. This connects directly to the switch return. The positive comes right off the battery to the driver.

I got everything connected and went to try it out. Turned it on...nothing. Turned it off and turned it on again, after a second or two, POOF! Sparks and some fire came out of the BMS board and a hole was in the electrical tape where there wasn't one before...Oops. I think something was shorted somewhere.

Took the tape off and pieces of the MOSFETS went with it. I think the reverse polarity failed at some point. I never get tired of the smell of burned electronics.

So hurry up and wait for a new BMS. I'll order one from eBay from a US seller and pay 3 times as much for it. Oh well. Hopefully the China parts will be here in a week or so. I hope nothing else is fried!

Stay tuned!

Aw, darn. Too bad about the fried parts. (been there, done that, it sucks but it happens from time to time)

:frowning:

Yah. I got 2 Bms boards from eBay from a US seller for like $10 for both. Not a bad deal, but twice what 2 from Aliexpress cost. I say if you aren’t breaking stuff you aren’t making stuff. If I has a dollar for every time I broke, fried, shorted, cut, burned something I could almost buy a GT70.

Man, that sucks — the sound of popping electronics is heartbreaking. The damage can end up so extensive. I hope you’re able to salvage most of it. What a fun project!

True! It really is annoying when you think everything is right, then you plug it in or hit a switch and poof, the magic smoke comes out that makes electronics not work anymore. It’s humbling for sure. This has beena fun project for sure! Not as bad as the 100W flashlight though. That was a deuzy.

So I checked things out and connected the driver and fan directly to the battery and everything works! Modes are fine, etc. Fan spins fine too...too good. At full battery power it will be overspeeding and even at 12v it's noisy (small fan with lots of blades).

I dug through my resistor stockpile and found a 120 ohm resistor maybe 3 watts? I forget. I tried a 100 ohm (the blue one in the picture), but it didn't slow it down enough.

All done! The fan is slowed down enough that the whine is mostly gone, but still pushes enough air. The batteries are only 75% charged, so I know it will be more than adequate when fully charged.

I don't know what I'll tackle next. Waiting on the new BMS and my Chinese parts now.

Stay tuned! Thanks.

Alright, so time to get back at this. I had been chipping away, but hit a roadblock waiting for parts due to a short circuit that killed my BMS. I mounted the battery pack and glued in the charging jack and the balance connector and made the gaskets for their cutouts. I finished devising a mounting system for the fan, so that's done.

In case you're wondering why the fan's important here's why. I ran it on turbo to see how hot it would get. The driver has a thermal stepdown that I haven't figured out how to change (it's Bistro), so it steps down at around 130 degrees F, but it gets there quick. Without the fan on, it's at 179 degrees on the MCPCB within 3 minutes and 134 on the heatsink itself.

I switched the temp gun to Celsius and took measurements with the fan on. I ran it for 4 minutes on turbo (before the stepdown) near the MCPCB and it never went over 55 C and stayed between 51 and 54 so about 130 degrees F. Yep, the fan works.

Since I got the reflector spacers from overseas finally (took a month and a half), so on to getting that sorted! I had planned on making one since suitable reflectors were either 1. too tall, 2. too expensive, or 3. too small (not wide enough). I am getting tired of making reflectors (it's the most tedious and boring part of these builds) so I decided to try one that was a similar size for the host. You might recognize it from the SST40 modded floating lantern.

I bought another one for the reflector and tried it out. It ran for maybe 2 minutes before I realized it was melting again. Even with the spacing ring it was so hot the plastic reflector melted. Scratch that. Back to the original plan...make one. Step 1: cut down the base of the original reflector until the focal length of the LED matches up well.

Good enough.

Step 2: make a base for it to sit on. I decided to use the top cover from a dead SSD drive I had lying around. It's cast aluminum or maybe even magnesium because it's really light, but really rigid. Maybe magnalium alloy? It will polish nicely. I traced around the opening of the reflector and did some geometry to find the center for the emitter hole.

In case you wonder how to do that, there are several ways, and the easiest is to use a center finder or a computerized measuring device, or you can do math, but I don't have a machine and I'm bad at math, so let's use chords. Draw 2 lines of a specific length between two edges of the circle parallel to each other. I drew 2 inch chords. Make sure the lines are the same length and distance from each other. T"hen draw a diagonal line from the origin of the first chord across to the terminus of the parallel chord. Repeat this on the other side, from the terminus of the first chord to the origin of the second parallel chord. The point where they intersect is the center of the circle. You can measure it to be sure, but it's always super-close. I can only tell a difference when I break out my calipers, so you're talking thousands of an inch.

That's as far as I got. I spent most of my day working on this and some other light projects. Next is polishing the reflector base and figuring out how to mount it and stick the whole thing together. I am waiting on my taps so I can properly tap the holes in the heatsink for the mounting screws holding the LED down. It's been almost 2 months since I ordered them from AE. Ugh. I'd have been better off spending the extra $5 and getting them from a stateside eBay seller.

I'll update soon!

Quik update. I ran into a major roadblock with mounting the cooling fan. The original design didn’t account for the fact the reflector and heatsink had to be centered in order the screw the bezel on… a big DOH! :zipper_mouth_face:

So back to the drawing board on that. I’m probably mount it inside the housing, but that has it’s own issues! I may use a different fan also, but probably not. I don’t know. At this point I just want to finish it, but between work getting and rain, and other things it’s stretching me. Good news is reflector is mounted to the base! I have all the wiring figured out too.

Stay tuned!

I hate those DOH! moments. I’ve had a few too

So I’ve been working in this in bits :exclamation: and pieces. I spent way too much time fooling with a way to mount the fan, but make it so its able to be removed. I had to make a bracket for it, and two mounting points to secure it to the host. I got that done. Then I had to improvise with the switch mou ting as well since the stock mount didn’t clear the heatsink. I didn’t feel like grinding off 1/2” off the heatsink to make it fit, so I hacked off the lower part of the switch mount and made a shelf. I cut the middle out and cut parallel grooves in a base the switch sat in and slid it into the gap in the shelf. That works great.

My mini taps showed up from China and I tapped the holes for the mcpcb screws and got that mounted properly. Got everything hooked up and ran a test. Bright flash from the led then only one die lights up so somethings not right now! Grrr. :exclamation: Not sure what happened since it worked fine before. :weary: I’m thinking the led was overstressed or something since I don’t think anything was shorted? Ugh. Back to the drawing board. New xhp70.2 coming! From America this time. It’s not much more expensive than from China.

sub

Just so everyone knows, the project isn’t dead. I had some major setbacks with emitters blowing (killed 3 xhp70.2 @ $18 each :zipper_mouth_face: from too much current-so I had to make a new battery pack (ditched the vtc6 for GA’s), new 30mm driver, and made a new driver holder with revised switch (the original melted).

Back on track! New emitter in the mail and should have it all done by Thanksgiving if nothing else goes seriously wrong.

Stay tuned

You persevere quite well.

That is an understatement! This is the most long-winded, hair-pulling, angst-invoking project I’ve ever done (and the most expensive) :zipper_mouth_face: BUT it is done at last!

So, the Quarantine Project is DONE. Funny thing, when I started this back in March, we were under a 'stay at home order' (a more polite rendering of quarantine), and now we're under another restriction. Go figure.

Here's some pictures of the finished item...This is the first type of this light I've built that you can remove the bezel by unscrewing it instead of screws. Sorry for the wonky pictures- it was late and I had worked an 11 hr day yesterday...

Inside-New switch from another flashlight that had to be modified to fit. You can see the rubber nipple sticking out of the handle. That's for the taller switch stalk to clear the case.

I chose this host because it's A) big inside and B) has a cool handle/stand!

You can see the cutouts for the balance and charging ports-no, they're not perfect, but it's the best I could do. I may fix that later. Maybe...maybe not.

If you look inside, you can see extensive modifications to the host to fix the reflector in place, make space for the bigger heatsink, and redesigned switch mounting (I broke it several times)

The improved driver holder and mount. I had to make a new one due to the new bigger driver (Mountain Electronics was sold out of the 26 mm version- so I got the 30 mm version). The reflector is held on by two big screws that thread into mounts attached to the reflector base. It's still a 4S fet driver running Bistro UI.

The LED is a XHP70.2 P2 bin 5700k 12 volt version. It actually has a proper centering ring this time! Now I'm getting fancy! The battery pack is now made up of 8 Sanyo 18650GA's to keep the emitter alive on direct-drive. The VTC6's were killing the emitter almost instantly when I had recharged the battery (the XHP70.2 can take some abuse).

I'll get some pictures of the beam later, so stay tuned for those. I have no idea of the lumens or throw yet. I'll measure the throw sometime, when I have time.

Interesting project. Waiting for some numbers. It seems some cheap-copy projects end up costing the same as the original flashlight would cost… (happened to me often enough lol)

Do you have any ports to let cool air in and hot air out?