5 Hours (now 72) + runtime....and counting

Unfortunately it seems me and little boards do not seem to get along that well. Perhaps my soldering skills or my attitude needs some improvement. I killed one of George's VIP 750 boards and now I killed a GD1000.

Enter the Micropuck SHO.....500mA of guilt free power in an incredibly small package. However, for the solder challanged, it's perfect.

On it goes to a heatsink, although not necessary, I epoxied it to the bottom of the heatsink. Put it into a 4 D M@glight with 4 Accupower Evolution 10,000mAh Low Discharge batteries and topped it with a Cree Q5 (I forgot how dissappointed i was with the Cree vs. the bright white Seoul P4).

It has been 5 full hours and the thing has not dimmed, not gotten hot, it has just plain been running incredibly well. I need to switch it to a Seoul and compare it to my other Seoul lights to see what differences in brightness I can see.

LESSON LEARNED: If you want a simple way to mod a flashlight with zero soldering skills needed, use a Micropuck that has wonderfully long lead wires.

LESSON LEARNED #2: If you need extreme runtimes, use NiMH D cells in a 4 D flashlight (Yes I will throw this together with some Emoli "big" batteries and see what happens, the Micropuck takes 4 to 8VDC as a buck driver, so I hope resistance in the M@glight eats up the say 0.2VDC that my Emoli have when charged to 4.1 VDC)

If 2 Emoli batteries will work, then a cutdown 3 D should be a perfect host for them and it will be interesting to see how long the Emoli batteries last compared to the 4 Evolution D cells. If I can get the good runtime, how incredible would that be?

Bob E.

Re: 5 Hours + runtime....and counting

5h is the very beginning of that runtime. At 500mA and around 3.25V, with an efficient buck driver and four 10Ah NiMHs, I'd be surprised if you got less than 20h.

Re: 5 Hours + runtime....and counting

Well, it is hour 10 and I can see some that it is not as bright as it once was. But I was still able to go outside and close up my shed in the back yard. Small and OK hot spot with lots and lots of spill....OK, incredible spill that was usable for walking and generally just lighting up the inside of the building.

Been playing with incan for awhile and forgot about LEDs and how amazing they are.

Just used my ZTS battery tester on all four NiMH batteries. I think I charged these three weeks ago after minimal use. Two were less than 10%, one was 60%, and one was 80%. Guess it's time to charge them up. The two dead ones were at 1.0VDC.

After recharging I think I will try this run time again. Thanks for the estimated time TigerhawkT3, now I will see what's up with these batteries. Perhaps I need to exercise them a bit to get them in shape. I got them around Christmas and really haven't used them yet.

Bob E.

Re: 5 Hours + runtime....and counting

In this situation, you'd be even better off as far as runtime if you were to use 4 alkaline D cells. Over the current range the Micropuck draws when in Buck topology, alkaline D cells would give you 13-14,000mAh capacity before reaching 1.0V each.

Re: 5 Hours + runtime....and counting

Thanks for the recommendation. I have four brand new Duracell D cells in the flashlight and am ready to start my test run in a few minutes. Will let you know how long it lasts.

Also I am running those NiMH Accupower D sized Evolution batteries through a couple of Discharge/charge cycles to see if the all come around and start acting normal. Everyone of them charged up nicely. Did the two suspect "dead" ones by themselves, then did the other two together that seemed to be of identical charge and voltage.

Bob E.

Re: 5 Hours (now 25) + runtime....and counting

OK, as you can see, 25 hours later......still running at approximately the same brightness. Absolutely no noticable heat anywhere on the flashlight.

Any guesses how long this will last? I am amazed at this thing!!

I just finished the same model with a Seoul P4 for my dad for Father's Day. I know he won't use it that much (maybe), but when he needs a light for an unknown amount of time, nice to know you have 24+ hours on new alkalines.

Bob E.

Re: 5 Hours (now 25) + runtime....and counting

We are now at 48 hours and I think it's dimmer, but I am not so sure. It sure looks like it did last night at this time, just ever so slightly dimmer, but it is still very usable light. Pointed it at my "test" object about 40 feet away, you can still clearly see detail. Pointed at the ceiling of my office, it lights up the room nicely, just as it did last night.

I don't see how it can last another 24 hours. We shall see.

Anyone ever done a run test like this before? I can't be the first one to build a 4 D LED light and just let it run out can I?

Bob E.

Re: 5 Hours (now 25) + runtime....and counting

A nice low forward voltage bin SSC P4 is a nice match for micropucks. Gotta love em'. A 350ma puck would drive such a LED well... and last even longer.

Re: 5 Hours (now 48) + runtime....and counting

Long live the mighty micropuck. :twothumbs
KISS engineering at its best.
I remember Wayne (ElektroLumens) saying that you could get 18 to 20 hours from two D cells (boosting the voltage) down to 1/2 brightness. That's what started me using them.
I just wish they were a bit cheaper.

Re: 5 Hours (now 48) + runtime....and counting

Don't forget to stop the test before the cells are completely dead. You don't want a leak...

Re: 5 Hours (now 48) + runtime....and counting

Thank you Essexman for joining in on the discussion. I will tell everyone that you were the entire reason for me using Micropucks!! When I first saw your tutorial, I thought that this is just the right speed for me. I made maybe half a dozen 2 D flashlights with Micropucks and kept half and gave away the other half. I then tried using the little boards (like George's VIP), and while the boards are cool with all their capabilities, there is nothing like the simplicity of the Micropuck. Again Essexman, thank you for really giving me the courage to start this little hobby!! See what you've done!!

TigerhawkT3, thank you for the heads up. I did not realize that when you run alkalines down to the bone, that they can leak. I normally don't run them dead.

It has now been right at 72 hours (unbelievable!!) and the light has noticably dimmed. My 40 foot test across the house is much dimmer, but you can still see stuff (much like an ordinary M@glight now!). However, I can still use this light to read in a book or magazine...anything you would normally use a flashlight for. Even 4 feet away is easily read. I will stop the test now before any battery damage might ensue.

72 hours....an amazing result using an ordinary Micropuck and 4 Duracell Alkaline batteries.

Bob E.

Indeed.