Can anyone step up for an AA/2AA only BLF budget flashlight?

[hank]

We’re actually in the early design/spec stages for a light though it may have deviated a bit from the poll.

Yay! please sign me up …

[LowLumen]

Some back of envelop calculations:

1000 lumens from XML2 U3 takes 8.36 watts.
8.36W / 2.5 Volts (2AA nimh at best) = 3.34 Amps.
A ‘dream’ boost driver may be 85% efficient at best with this current….
3.34 x 1.15 = 3.84 Amps draw from batteries.

Not including losses from springs, switches, contacts, etc, 2400mAh battery will get you 37 minutes runtime at 1000 emitter lumens. ….at best

[ReManG]

@LowLumen

Some back of envelop calculations:

1000 lumens from XML2 U3 takes 8.36 watts.
8.36W / 2.5 Volts (2AA nimh at best) = 3.34 Amps.
A ‘dream’ boost driver may be 85% efficient at best with this current….
3.34 x 1.15 = 3.84 Amps draw from batteries.

Not including losses from springs, switches, contacts, etc, 2400mAh battery will get you 37 minutes runtime at 1000 emitter lumens. ….at best

Or a FET driven 1x14500 light for 1000+ lumen. 11 minute run time, if you can hold it… Plenty of other more useable modes though…

I am on board for developing a great boost circuit driver.

I am also on board with hosting a group buy for a 1x14500 only pocket rocket in the mean time to tide us over…

Also remember that the X5 is coming out in Kronologicals group buy for the X6/X5… That one will be a 14500 only light as well…

[Fritz_t_Cat]

@djozz

…. Further, 14500 only will not do it for me, what makes an AA light strand out is the use of alkalines and safe NiMh batteries, it makes this light suitable for gifting and lending out. The main problem is the boost driver, it must be efficient, programmable (Attiny based?) and probably 15mm diameter. There have been some attempts, one still in progress, once that has been sorted out this project can take off.

Ni MH have about the same energy storage as 14500s, so with a good boost driver there is really no advantage to taking Li ion cells. It needs room for a large induction coil, and it should shut off at more than 2 V. But see below.

@KeepingItLight

Efficient, constant-current, boost driver; no PWM

A boost driver has intermittent output current. Unless the frequency is so high that that can be smoothed out with a capacitor, one can’t ask for truly constant current. Modes should work by increasing the fraction of the time it outputs, to reduce the average current.

[Fritz_t_Cat]

@TexasLumens

@Fritz t. Cat

Beautiful shapes have compound curves, so they are almost impossible to prototype on a manual lathe. The best way would be to make a prototype in clay and then have it produced on a numerical control lathe. There was someone on here who had worked with NC. There was a thread of beautiful 3D printed lights, but none of them could be mass produced.

I love clay… but to do this in clay would be a total waste of time…other than the enjoyment. When folks decide what they want, we can do the light in CAD and render it out. That way, when the design is complete, we can CNC the prototype and go from there. If a clay model were produced, it would need to be reverse engineered or laser scanned to get that shape into a digital format so we can work with it in the shop. You are exactly correct about the manual lathe being a limitation. That is why we currently run CNC machines and are upgrading the entire shop to even higher production volumes & capabilities.

The design possibilities are endless. The capability / ability to produce those designs is almost as endless. I think each of us has “Something” we like in the design of each light we own. That curve, this offset, those fins…etc. .

We can’t put everything everyone wants into one light. It takes multiple lights. That is what we have based the shop upgrades on. We needed the capability to be faster and more agile in the design & production of lights.

I think watching what folks like, want, don’t want, and crave is highly interesting. TL

I still think that ideally, one would use clay, but I agree that would be too ambition for this discussion. I think clay is better than CAD because one has more direct control and can feel what one is doing. It matters as much how the finished light feels as how it looks. Maybe more important, the designer should look at, and preferably feel, pottery. When designing for an NC lathe, one should not ignore the thousands of years that people have been searching for more pleasing bodies of revolution with pottery wheels.

[LowLumen]

I’ll be watching with interest but I think you will need to find an off the shelf step up converter chip with higher current handling than PAM2803.

Here is some work with that chip:

https://budgetlightforum.com/t/-/31239

With a larger coil & cap it can get to 1Amp out from 2AA. (input current must stay below 2 Amps)

I use the DX SKU 25505 single mode with modest output for 1 & 2AA. Within spec it will do 80-90% efficiency. (for my use here, run time is more important; top bin Cree LED’s will now get to 500 lumens at 1 Amp.)

For sure there are better higher current 2AA drivers out there from Fenix, Olight, Eagletac, etc.

As stated earlier, the key is to get the driver.
Happy Hunting.

[hank]

laser scanned to get that shape into a digital format so we can work with it in the shop.

Hmmm, give every person a lump of clay to put over a dummy battery tube, and hold in a comfortable grip — then laser scan that and use it to make a perfect hand-fit flashlight?
Nah, that’d be over budget …

[bikenber73]

Who builds County Comms lights?

This one seems nice but too expensive for me to give away.

[djozz]

For me, the challenge would be a 1xAA light, not 2xAA. So, to get 1A out of 1 AA cell with Attiny control would be my holy grail!

[Sprinkles]

I have a weak spot for a good AA/2AA light. I’m actually tracking down a 2AA host to mod with some older AA drivers I had apparently stashed away for a rainy day. I’m anxious to see where this goes since I’m already looking at other AA options to my EA11 and Thrunite 1A. The Manker T01 is certainly promising, but i would MUCH rather support this build than a production light. I’m not too particular about the shape, but the usability and programming is key. Oh yeah - the “wow” factor is important to.

I’m also curious to see what CalvinIS has in store…

[presterjohn]

I think after reading through this thread and digesting much of what has been said I would like to see the BLF X5 (In type 3 black aluminium) with a longer 2 AA cell body as light for this GB. The X5 seems to tick all the boxes and size and looks wise it would kind of be what the Mini maglite should be if they kept up with the latest technology. I would presume it would be doable in the $20-25 level too which always seems to get a lot of interest in GB’s.

[DavidEF]

@presterjohn

I think after reading through this thread and digesting much of what has been said I would like to see the BLF X5 (In type 3 black aluminium) with a longer 2 AA cell body as light for this GB. The X5 seems to tick all the boxes and size and looks wise it would kind of be what the Mini maglite should be if they kept up with the latest technology. I would presume it would be doable in the $20-25 level too which always seems to get a lot of interest in GB’s.

Except that the X5 doesn’t have a boost driver, so we still need that, too.

[mattlward]

I have one in 2AA, but have been unable to purchase a single AA tube for it. I would love to find a single AA tube, used with a 14500 it would be a great little light. They are very well made, I like it better than the Solarforce L2r.

The other issue is that there do not seem to be any really good driver out there. I have a couple of older AA lights that could use a bump, but really need a driver with the new LED.

Matt

[vestureofblood]

@djozz

For me, the challenge would be a 1xAA light, not 2xAA. So, to get 1A out of 1 AA cell with Attiny control would be my holy grail!

You said it. I would join the band wagon for a 2AA light, but an Attiny13A driver for a 1AA light would blow my mind.

[Rufusbduck]

There are more new members every day and some have EE knowledge so keep asking and sooner or later it will happen. Remember it took several years to get a programmable 17mm buck driver. If someone were paid to do it then it would get done sooner but as it is you have to wait for someone with a hobby interest to take it up and run with it. Testing, boards, and parts costs money so setting up a way for people to pitch in could accelerate the process but you first need to find your EE. Then there’s always the DIY method and you might find lots of help where you might not find volunteers.

[emarkd]

One of those (kinda) new members here, although I’m not an EE. Sorry. Just wondering, how did the other drivers get designed? Obviously some smart folks have put in the effort here before, folks like Wight or Alex Wells, maybe. Those are names I’ve seen but know nothing about. Are they not up to this job? Do they just not want it? Have they left the community?

For us new guys, what’s the story there?

[calipsoii]

@vestureofblood

but an Attiny13A driver for a 1AA light would blow my mind.

Ah heck, I just can't resist VoB :)

• 14mm diameter
• ATtiny85V microcontroller
• 0.7 - 3.0V input voltage
• 0.4 - 420 mA LED drive current (XP-G2; 1x Eneloop)
• Full current-control through all drive currents
• Off-time capacitor mode switching
• End-user programmable via custom firmware:
• • 1-4 output levels
  • Brightness of each output level fully adjustable
  • Toggle between classic mode memory, hybrid or no mode memory
• 2xAA/1xCR123 not yet tested but should work with higher LED currents possible/likely
• Li-ion likely to run direct-drive (at least until the sense resistor burns out :P)

[MRsDNF]

Nice. Where do I order from?

[grayski74]

@calipsoii

@vestureofblood

but an Attiny13A driver for a 1AA light would blow my mind.

Ah heck, I just can’t resist VoB

• 14mm diameter

• ATtiny85V microcontroller

• 0.7 - 3.0V input voltage

• 0.4 - 420 mA LED drive current (XP-G2; 1x Eneloop)

• Full current-control through all drive currents

• Off-time capacitor mode switching

• End-user programmable via custom firmware:

• 1-4 output levels

• Brightness of each output level fully adjustable

• Toggle between classic mode memory, hybrid or no mode memory

• 2xAA/1xCR123 not yet tested but should work with higher LED currents possible/likely

• Li-ion likely to run direct-drive (at least until the sense resistor burns out :P)

!!!

[djozz]

@calipsoii

@vestureofblood

but an Attiny13A driver for a 1AA light would blow my mind.

Ah heck, I just can't resist VoB :)

• 14mm diameter
• ATtiny85V microcontroller
• 0.7 - 3.0V input voltage
• 0.4 - 420 mA LED drive current (XP-G2; 1x Eneloop)
• Full current-control through all drive currents
• Off-time capacitor mode switching
• End-user programmable via custom firmware:
• • 1-4 output levels
  • Brightness of each output level fully adjustable
  • Toggle between classic mode memory, hybrid or no mode memory
• 2xAA/1xCR123 not yet tested but should work with higher LED currents possible/likely
• Li-ion likely to run direct-drive (at least until the sense resistor burns out :P)

Welcome to BLF :-) That is one heck of a first post calipsoii ! That sounds and looks like a great driver, both the hardware and the software! So what's the story? You designed it and kept it a secret till now?

edit: I should check CPF a bit more often ;-) http://www.candlepowerforums.com/vb/showthread.php?373167-Build-Log-The-1-5V-Project

That is a great build log, I'm enjoying reading it :-)