Just talked to a co-worker. He will solder for me. Those 30Bs are rated for 5.9A, so they should be good enough, I hope.
I don’t think this light was ever designed with the intent of being run on one battery.
Sure it can be run on one battery in an “emergency situation”…… but that would not be a situation where TURBO or higher modes were the main concern. It would most likely be a situation where a bit of light was needed.
The Q8 could then be run on one battery at a much lower mode, putting out the “bit of light” that was needed without causing the extremely high Amp draw that would collapse or melt down the spring.
I mean, come on guys: I am not a monetarily rich person myself by far. But, if I can’t afford 4 batteries for this light… I most likely don’t need to be buying the light in the first place. Or if I do buy it, so I will have one of these fantastic lights; I’ll just have to use it in a lower mode till I can save up and get 4 batteries.
The Miller makes a perfect point about getting a LiitoKala Lii 500 charger. They work great and the price he quotes is just about right. You might even get it a bit cheaper with a coupon.
If that is to much for you get a Lii 100 or a Lii 202
Sure, with the Lii 100 you would have to charge the cells one at a time. With the Lii 202 you would have to charge them in pairs. But that would be a way to get into a charger cheaper if you have to.
I am not saying this to be mean or sound like I know it all……. cause I do not. 
But this light was designed to run optimally on 4 batteries to have safe access to all it’s lighting glory.
If you choose or want to run it on 1 or 2 batteries …. don’t expect to have safe access to the top end of it’s capabilities. Simple as that.
Going back to Dales 2017 Corvette Grand Sport example.
It requires certain tires to reach the optimal results of it potential.
Sure, you could mount some 105/40-19 (Front) & 115/35-20 (Rear) tires on it (if you could find them that is … 
) , or “rig” it up to accept something else equally as inferior & stupid. BUT, in doing that you can forget completely about any of it’s sports car features & IF you are lucky it might get you from point A to point B at a very slow rate of speed.
And even IF you do go with the recommended tires… you better use all 4 IF you even want it to move at all.
At least the Q8 can be safely used at very low output with one battery even. To me, that is a win……. :+1:
- a bunch on this.
Since we are using car analogies, that Corvette can probably run on regular gasoline if you want to save a few bucks at the pump, but you can expect performance to take a hit, but fill it with premium or racing fuel, and then watch it go. Chances are also pretty good that if you DO try to run regular fuel at the track, you are going to do some damage.
For anyone considering soldering solder blobs onto flattops, this should help:
Most of that is accurate. The part of using a small tip is wrong. A small tip doesn’t carry enough heat, you want a large tip. That way it will dump a lot of heat energy into the battery top very quickly while still maintaining enough heat to liquify the solder. This allows for a short “tip on battery top” time.
I would also use a damp sponge or paper towel to cool the blob right after soldering to get the heat out quickly, preventing it from spreading to the rest of the battery.
I don’t think you need a 100 watt soldering iron. Mine is 60w and worked just fine.
Adding rosin or flux to the battery top is also a key to doing it quickly and effectively.
Maybe someone could make a quick video showing how it’s done?
THESE solder blobs of Jerommel’s are the best I have ever seen.
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And RIGHT HERE he tells how “he” does it. :+1:
EDIT: Well now I have seen some more from KawiBoy1428 RIGHT HERE
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Please don’t mistake what I was saying, I’m in the crowd that can only dream of a Corvette, for reasons like the initial cost, tires, insurance, yada yada yada. I bought a Cadillac Seville once, used but in immaculate condition, got it pretty cheap and loved it a great deal! Then things started going wrong, simple things that cost way more to fix than a regular car. Which got me to looking at some of the other “regular” maintenance stuff. For example, it had magnetic fluid road sensing shocks all the way around. To replace the shocks would’ve cost some $7,000, or so I was told then. So sometimes we in the lower classes don’t have the most exotic stuff not just for what it costs initially, but the maintenance and repair costs and the price of ownership as well. Be that higher insurance, lower gas mileage, or extra cells required.
Edit: Brian, really? “No technique is required, just a soldering iron, flux, and solder. Anyone can do it.” That’s how you get someone to blow up a lithium ion cell in their face! While it may be pretty simple, remember that those who don’t already solder may apply an 80 watt iron for 60 seconds… not knowing the difference.
Small tip small blobs!! Less Heat…
Well, yeah. Maybe I should have qualified it a bit more. But others did that for me. Maybe not everyone researches things as much as I do. So yes, you’re correct. My point was that it’s not difficult to do.
First I have to say I don’t like doing solder blobs, on the occasion that I’ve done it I have used solder paste as it contains the flux and cleans/etches at the proper point in the heat cycle. The solder liquifies and you know you’re done. A small blob to start with sticks the solder to the cap of the cell. Easy to then add solder without actually putting the soldering iron tip on the top of the cell itself, gather solder on the tip and let it touch the existing solder blob, when the blob melts it will pull the solder off the iron and grow the blob. Easier and safer to do this a few times and get the size you need as compared to doing it all at once. This is what Comfychair taught me quite a while back.
Well I am planning to give away some Q8 as gifts ;
I expect to give,
40 $ Q8
20 $ Litikola 500
Batteries not decided but from 15 $ to 40 $
5-10 $ A proper case
5-10 $ some sort of diffuser
So quite expensive gift but a good one for about 100$ or a little more.
Can I be your friend? Nice gifts!
I strongly disagree with you Dale.
I think it’s best to do it all in one, 3 second or less, shot. Then cool it quickly within a few seconds.
As soon as you heat the top of the cell the heat starts traveling downward so you want to minimize the time and heat you put in. A few seconds is all it really takes. Then in the next few seconds cool it with a damp sponge or napkin. The heat gets pulled out quick and stops flowing to the battery below.
Anything more than 3 seconds of tip contact is just not necessary.
Folks- Please forgive me for asking as I cannot find it- But is the BLF Q8 still available for pre-order or group buy? I’m sorry but my cataracts are acting up tonioght and I’m having a hard time seeing all the posts and specs. I would like to know morew specs and pricing etc if anyone vcan be of help to me… Thank so much… I have a Niwalker MM25MB V2 soda can and an older Sun Ray King flashlight. I love flashlights too much
Yes, how many do you want?
Heck yeah… sign me up as a “friend” to if you need more. 
Sometimes a too small a tip will drop in temperature below the melting point of the solder once you press it against the battery top. Then you have to hold it there 5 or 10 seconds for the heat to build back up. That’s not good. The more heat the better. Add it quick, then cool it off quick. Time is what you have to be careful about. Once you add the heat it starts heading for the battery. So cool it down as soon as the blobs are formed and loose their shine (2 or so seconds of removing the iron).
I guess your not talking about a fine tip for precise detail work, but a more general size tip?
Folks should use the biggest tip they have. Chisel shaped tips work the best.
I did not look at the thread for a few hours and I am now behind the response curve.
Conductivity of springs: already pretty nicely explained in subsequent posts.
In a (sort of) short reprise, the whole volume of the spring wire is conducting current. The coating is mostly to keep spring steel from rusting. The steel is the major conductor. If you had a stainless steel spring wire, no coating needed. But as I recollect, it does not have optimal characteristics for springs, has a somewhat higher resistance, and I believe is harder to solder. But, when I last looked at these things, steel was made using indentured servants working bellows for the charcoal fire which allowed (with additions) the reducing of iron from the ore. So keep a grain of salt handy while reading.
DC current does indeed use the entire volume of the conductor. As the frequencies of the current (alternating current) increase there is a general migration of current (due to skin effect) from the whole volume to the outside of the conductor. But you need to go to significantly higher in frequency than involved here to get the current sitting on the conductor surface.
Phosphor bronze is both a better conductor and less prone to corrosion. Nice and springy as well. Gold, silver, etc. plating would also improve the corrosion resistance, but probably not necessary. The possibility of Phosphor Bronze is interesting. Done in similar cross sections, this would improve current to the bright bits. I am guessing that a PB spring replacement for the main spring and elimination of the second spring would still yield a higher delivered power to the LEDs. In this development the emphases has been on current, but lowering the resistance in the spring would up the available current (within the constraints of the regulator electronics) and also increase the voltage across all the light making parts a bit. That might be good or bad.
Now a disclosure: I don’t care how bright the light can get. I am one of the GA users. I would have liked to have the tube and stuff able to use Elon’s batteries in the future. Perhaps a nice project for us to do the Q8 in nextgen battery formats. Maybe only a tube needs to be changed. I want it to run as long as possible at fairly low light outputs. In an emergency, I am unlikely to try to use a flashlight to start a (forest) fire, see if I can melt a battery, or to heat survival food on the head of the light. So battery POWER required to be delivered to the LEDs for a given light level is more important to me than simply more amps. The more voltage drops in the power train (with constant load current), the more power is being consumed from the battery for the same amount of emitted light. Power is, in one form, VxI. If, for the same consumed current, the voltage supplied by the battery can be higher, the battery is operating at a level which is consuming less overall power (the heat generated in the resistances in the power train). Hence, battery life is a bit better.
Oh, protected GAs need to work.
So, for any given LED output, less wasted POWER is required from the battery with lower resistance in the total circuit. May not be a significant value; but it is there.
Oh, I am not fond of solder blobs. They are relatively soft (at supportable application temperatures) and can wear in normal use. This seems like a bad idea. Particularly for a use that involves sliding blobby battery posts against Copper rings, when screwing together parts in the battery tube, for normal use. Clearly there are many that find no problems with this. Solder can form an oxide (with today’s air; also various sulfates, etc.) and cause a voltage drop. Plus the aforementioned pressure and friction. Just don’t like the idea.
only slightly off topic, i have not received an email update lately, and there have been several new posts…i’m still subscribed it says…i just don’t want to miss out when it comes time to order this…anybody else having this problem? anybody know how i can fix it?
Always know that this head gets several posts a day, so if you don’t see an email notification, then just come here manually. Viewing the page seems to reset the email notifications.
Also, there has been a lot of maintenance on this website lately. We were offline just a couple hours ago, in fact. So this might be messing up the notifications.