One longer tube for me please.
Thank you
@ Sharpie. I believe that there is in my case a poor connection between the battery positive and contact to the driver which when hooked up to the power supply this poor connection is taken out of the equation.
Battery sag is not the case here causing low current readings.
one tube please!
I am wondering this as well
Edit: the tail cap screws directly to the head so the threads match up. What would be the benefit of 2x cells in series for a flashlight? Longer runtime? Would this be a problem with unprotected batteries that will be charged separately?
Did not even think about screwing the tailcap to the head :steve:
I do not have anything in mind yet, but to have the option to do a build with a 6V led, or drive a XM-L2 or XP-L at higher current than with 1xli-ion is a nice idea 
. Lego away with this light!!
@Krono: 1 tube for me please 
Doh! You’re right, I tried it right after I hit submit on that post. :bigsmile:
So batteries in series double voltage… Why indeed on this light? 6 volt emitter would be cool like xhp but it’d kill the nice beam profile . a bigger reflector would be better for that. If adding more cells I’d rather keep voltage and add runtime.
One tube for me as well please.
Thought I post some pics of the D80, for those to gauge size and finish if they haven’t got one yet.
With some of it’s other BLF SE stable-mates…
Compared to a C8, not how much more compact it is.
And compared to some other lights that get used for the same use, I see them as the ‘competitors’…
I will try and get some beam shots comparo’s latter tonight.
There could be something to this. The brass button on the bottom of my driver isn’t flat. Its got a very thin, very small raised lip all around the edge. Using a flattop cell would result in it only making contact through this tiny lip and not the majority of the button’s surface. A button top cell fits inside this ring and makes contact with the entire top of the button.
I’m equipped to test this because I have Samsung 30Qs in both button top and flat top, so I compared them. Using my shunt-modified Fluke meter and some short 14 gauge “custom speaker wire” ofc copper leads, I measured the following at the tailcap:
- Flat-top cell: 3.34 amps
- Button-top cell: 3.46 amps
That’s about a 4% increase in current. I’m not sure that’s significant enough to matter and could even be related to the capabilities of my individual cells, but it is what it is.
While I’m typing, I’ve also made a couple other measurements with my light, measurements that mean more to me than a few 10ths of an amp at the tailcap 
Stock light, straight from the box, using a button-top Samsung 30Q, I get 28,116 cd = 335m throw, measured at ~5m. That’s pretty good! Just for grins, I replaced the tailcap spring with a good gold-plated spring from MtnElectronics. I didn’t even remove the board from the tailcap so i did not do a bypass. My reading increased to 28,676 cd = 339m throw. That’s only a 2% increase in cd, but it does show that the included spring has some unnecessary resistance in it. Next step is to get that pesky retaining ring loose so I can do a proper bypass.
Also did some tailcap measurements.
Brand new Samsung 30Q’s charged on a 4Sevens charger. This charger is known to not quite make it to 4.2v, but there is little I can do about it, because it’s the charger I’m using.
Battery shows 4.13v on this DMM. If I dug out my other DMM then it’d probably show 4.15v on that one. The battery may show higher voltage off of my Xtar charger too. But usually only 0.1-0.2v more.
Completely stock D80 is showing 3.56amp at the tailcap with 12AWG leads:
The same battery only moments later in my Direct Drive and Positive terminal by-passed, de-domed X6 SE, was pulling 5.34amps 
Now when I post up some beam shots later on I think you’ll be pretty amazed and not in the way you think you’ll be. 
One tube for me as well please.
I’ll take 2 long tubes. Thanks.
I’m debating between 2 or 3 long tubes but you can put me down for 2 for sure. Thanks
Legoability, while a second battery tube will indeed screw onto the first, the depth of threads is different on the but as compared to the head such that the initial battery tube won’t thread deep enough into the second tube for the o-ring to make contact. Modifications would have to be made, but of course, where there’s a will there’s a way.
(Look at the ‘page source’ of the imgup page. Find the real link to your photo and link to that, rather than the webpage built around your photo by the hosting service.
This is the direct link to the photo:
http://imgup.io/images/2016/01/03/38a85fd54598e1ab5e23cf284bd64f7d.jpg )
Some beamshots as promised
Please note, these have been taken with an iPhone 6 Plus, not an SLR. So these aren’t the last word in showing output differences. But they do show beam profile and throw differences very well.
So despite the relatively low amp draw of the D80, it seems to out perform the direct drive de-domed X6 on every level. Not sure how but it does. And it significantly out throws it too, despite the small size difference in reflectors. Maybe my de-domed X6 is feeling a little old now… although it hasn’t been extensively used. And it does still out performs my stock X6 SE, which is easily trounced by the D80.
The only oddity, although not a negative. Is how well the SST-90 powered MMU performs. It’s not as throwy, but seems to easily pump out as many or more lumens. It easily matches my BLF A6 and with similar beam profiles. So either FourSevens lumens are vastly different, being that they rate the MMU at 800 lumens ANSI. Or it actually makes a shed load more light than claimed.
Oh and one last word on the PWM…. such a shame, given how well the light performs. But I really think I’m going to have to swap the driver to make it a usable light.
cough cough…
D80 on the right.
Those beamshots are definitely surprising.
I do believe I said way back there………….
If it has 1 amp and shines as or brighter than a 5 amp light that’s fine by me. If it has 100 lumens instead of 10,000 and shines just as bright that’s fine by me also. I mean honestly I have a 170 lumen Brinkman in there that is struggling to make 1.5 amps at the tail, that will out throw a couple of my lights that are 500 and 750 lumens and both of those doing 2.3 and 2.8 at the tailcap. Although the Brinkman is a deep reflector little thrower styled for that purpose, I still get about as much light as the other 2 down range and almost as bright with less than half the amps and 1/3 the lumens.
First, I wasn’t insulted. Second, I understand the arguments for the use of unprotected IMRs, especially in a high performance light. I don’t care that Im getting less than 100% of the potential performance when I use the cells I already own. I’m never in the high lumen modes for very long. I’m mostly down at the low end.
You make me wonder too