That’s a curious optics choice. Why did you combine TIR and reflector this way?
I’m pretty sure that’s not a TIR lens. Probably a common 44mm lens you can buy from AliExpress.
Brain fart, I was just looking at some TIR zoomies. 
I meant convex lens and reflector.
I did some research on it after I got it together. The beam was horrible. All flood, no hotspot. Since I was wanting the most out of the setup I could, I was thinking the COB led with the square die would have needed a really big reflector, which I couldn’t find for under $100, so i stuck a somewhat big reflector overthe 44mm glass lens. Under the lens is a small square reflector (maybe 3/4 inch tall by 1.8” wide at the top) that fits around the die. You can see it’s outline around the edge of the spill in the beam shot pic. I may find another setup for it though. Does anyone here have suggestions for one? I’d like to explore options.
Yes it was really hard. The battery was the worst since it takes up a lot of room. Everything is crammed bsb in there pretty tight!
How about a power tool battery they are made to be taxed badly and its already setup in the right config for you? I am not sure if you have Aldi over there but i scored a Aldi tool battery typical 18v 4amp hour that uses Samsung 20Q cells for like $20 AUD.
@Sirstinky, you should get some LEDs rngwn is selling, some 5700k and 3500k goodness.
Can’t say anything about them since I didn’t receive them yet, but Maukka testing them said that they are great.
What are LFP batteries? I never heard of them.
For the parts list you need a lantern-style, also known as a “floating” flashlight. Sourcing these is tricky since you need an older one that takes the 6V batteries. I get mine from thrift stores for like $3. The newer LED or the incandescent ones work that are everywhere and cost under $15.00.
You do want one that’s on the long side if you want to run 8 cells. The Ozark Trail, older Rayovac, Dorcy, Lumilite, Eveready work.
A 100W COB led from eBay, Aliexpress, Banggood, or Amazon. Cost about $13. Get the good quality one from reputable sellers. Lots 9f cheap ones are junk, dead LEDs, low output, short life.
44mm reflector cup and glass fosucing lens set to go on the led.
Find on eBay for like $5.
Heavy duty switch. Has to be 12V, 5A minimum. I’m using automotive type latching one. They are like $6 for 5 on eBay.
Heatsink and fan. I’m using an Intel heatsink for a Core 2 Duo processor because it’s low profile ad works pretty good- I say adequate. It must be rated for a 95W minimum TDP processor. Cost me $15 shipped. This one is getting hard to find for under $20 but you can use one for a lower tdp but your fan has to run faster for more airflow since you are dissipating 100W of power.
The fan is a 12V 70mmx25mm fan. Get the slimmest one you can find like 80mmx10mm or 80mmx15mm. That 10-15mm makes a difference in space saving. I got mine free, but new they’re $5 up to $15 for really good quiet ones.
Boost converter. Must be CC/CV and rated for minimum 150W. The ratings for them are so overblown, you need to go with more than you need. I got my 250W one on eBay for like $12.
For batteries you can go li-ion 18650, 18500, or even 26650 if there’s room. You want to run 3S or 4S. I recommend 4S and at least 10A current handling since the draw on the batteries will be 10A. That means 30Q, Vtc5 or Vtc6, 18650GA, HG2, Molicell P26, etc. You could try to make a 6S or 8S setup, but you need a charger that can handle 8S (they’re expensive), or go with two cheap 4S battery holders, but they’d need some modifying to handle the current. I thought about that recently. Either way this is the most expensive part of your build!
You need a 3S or 4S battery management board for the batteries since you need low voltage protection for the series cells and for proper charging. Around $7-8. eBay is the best place.
3S or 4S balance lead for charging. About $5 on eBay or Aliexpress
You need a balance charger for lipo or li-ion. They’re cheap like $15-$20 for an iMax clone on eBay or Aliexpress.
Assorted screws, self-tappers or machine 6-32, etc.
Then the hand tools and miscellaneous stuff…Dremel tool with grinding, cutting bits, drill, small files, precision hobby knife, super glue, JB Weld, spare hosts for parts, etc.
There are other things, but that’s the bulk of it. Total cost for my build was around $50.00. For a 6500lm light that’s not bad. Plus there’s more power to be had if I get better batteries since the driver isn’t breaking a sweat.
LFP = LiFePo4. Less capacity than LiPo but far more docile when malfunctioning. I have never saw one caught fire yet on the internet. At worst it vents smokes when shot with nails through it. The voltage is lower at 3.2v nominal.
Great thing about this is that, with proper BMS, you could really get away without balance charger. Just shove 14v at the BMS terminal (for 4s config, also watch the current). This might not ideal in term of lifespan, but hey at least it won’t set your house on fire.
They have TIR zoomies? Wow where do you find those? Can you get hosts?
I never heard of Aldi brand in the USA. I think I considered that before and it’s a great idea. Problem is good batteries are expensive (name brands are like $80 for a 4Ah) and I dont trust used ones since they’ve probably been abused.
Other question is how do you charge them? Do you disassemble them? I know the tool chargers don’t work with off the shelf hardware.
I have a 7*7*7 cm LFP4 pack available. Will that one fit in?
Yes that will fit most of the hosts out there, but it might be a tight fit. Anything that’s 65mm wide (18650 battery size) will fit, but the length is where you might have trouble in a smaller host. This is why I could only fit a 4S2P in there. L
Here you are:
I’m not aware of anyone selling hosts.
I would assume that adding a lens to a reflector this way would:
- reduce spot diameter
- make flood brighter
Apparently my prediction is wrong, so I am unable to suggest what you could do better.
You might try to find a narrower lens if you want better throw.
However, the narrowest one you can realistically find will be 60 deg angle ones. Which probably still won't make a good thrower. The spot diameter of the light will be equal to the distance from the source to the surface. (i.e. if you are 10m away from the wall, the spot size will also 10m in diameter).
There also exists 45 or maybe 30 degree lens for that, but it's only in alibaba. You will have to purchase in volume for that.
I checked Alibaba and none of those would work. None of the off-shelf options for this setup are ideal without extensive modifications.
I’m contemplating options, like seeing if I can eliminate the glass lens and go with a straight reflector I already have on there. That would require reworking the whole front end, so maybe or maybe not something I’ll take on. I’ll post it on here if I do, but for now I’ll focus on the battery. 45 sec of max power run time is lame.
I have laptop batteries lying around from a 12 cell 14.8v, 68Wh Paco out of an early 2005 or 2006 Compaq laptop. I think I’m going to need some high drain cells though…
Thanks for sharing. It looks like you’d be limited to led lenser of you wanted actual optics in a zoomie, but they’re really expensive like over $100. Matt Smith reviewed two of them from his Bass Pro Shop comparison and they’re great, but too expensive. I am planning a sst-40 fet driver build coming soon.