This continues over from "ARC LS helmet light and headlamp prototypes" where I brought this up originally. See that thread for initial background.
Silviron. I would definitely be interested in a couple of the 'inside the Mag head' adapters. I am not sure how well this will work with the 5 watt model, due to heat issues. That is something that we would have to find out, in due course.
The idea here is to increase runtime while using readily available and cheaper alkaline cells. Normal flashlight use, is not a constant on. The principal exception, is in caving, and usually done with headlamps.
The ideal and most elegant solution, would be to make a 2C pack with Arc LS head adapter, but we are talking about increasing options for those of us who have a 2C and/or 2D Mag-Lite and desire to use the Arc LS head inside the Mag head.
Of course, once LEDCorp gets a reliable supply of LS emitters for 2 Cell, this would be a non-issue. Peter has enough on his engineering plate right now, but maybe the 2C pack could be something for the future. [img]images/icons/wink.gif[/img]
Silviron, this adapter is simply an option to add versatility to our lovely Arc LSes. [img]images/icons/grin.gif[/img] [img]images/icons/grin.gif[/img]
Put me down for 2 adapters, once you have things done to your high standards.
I just got through making one of these, and it works fine. I'll post some pictures after I get some sleep, and maybe start a run-time test in the next day or so.
I'd better not make any firm promises about selling these yet.... I'm just not good enough on the lathe yet to turn them out at a real reasonable price. (to me, $10.00 each would be sort of reasonable) but the way is stands now, I don't think I could do them for less than $15.00 each, and I'll need more practice on the lathe and get or make some more tooling to even be able to do that.
If there is enough interest on these, I'll make it a priority project though.
Made of aluminum, threaded inside to screw on Mag bulb post. Insulator is turned out of Delrin, and has a 1/8 inch diameter copper tube (with solder blobs on the ends) to provide electrical connection to positive contact on ARC head.
I didn't want to ruin the reflector on the mag light so I didn't cut it out to make room for this setup; easy enough to do if you wanted it that way though.
This mod is COMPLETELY reversible- No more complicated than changing the Mag-light bulb, and screwing on the ARC head and replacing the Mag head.
If I decide to produce these things, production units will probably be slightly different, but not something anyone would notice.
If someone wanted to run the ARCMag on a 3 Cell (or more) light, a resistor could be incorporated into the insulator to drop the voltage to a safe level for the ARC head.
I've started a run-time analysis on this unit- After a half hour continuous operation on two fresh Rayovac Maximum + D cell batteries (Dec 2009 expiration) here are the results:
Start: 274 LUX @ 1 meter / 85,200 LUX in contact with meter sensor with the Mag "lens" in place.
Without Mag "lens" it is 281 / 88,900 LUX
I have been running on the graphing test meter with the Mag "lens" in place. The ARC head is a bit warm- but I don't think dangerously so. I don't have my temperature probe handy, but I'm guessing it is about 140 degrees F, maybe 150.
One potential use w/o mag head, is indirect light, by setting the Mag on its tail. Useful during power outage. Speaking of that application, a nice base to insert the Mag body into (plastic with pvc pipe?).
Perhaps some sort of formed shroud with o-ring on the LS head end (inside), that would push on over both the LS head, and the Mag body, taking advantage of the o-ring on the Mag body. First things first. (I'm thinking of the LS3 here)
IF the temp is too high or there are signs of rapid increase of temperature, then a pvc or aluminum shroud to fit over both arc head and oustide of mag body. Maybe an extended adapter, with shroud on base. Don't even know if it is possible for either C or D bodies.
The temp probe is going to be critical here, as heat is a major factor.
I do know that if a 2C pack ever becomes available for the Arc LS, I will buy at least one. [img]images/icons/grin.gif[/img]
I am great at coming up with ideas. My problem is that I have neither training nor tools to try out the ideas. Income is another factor: less than $400 per month Socsec disability. My DMM is the only leftover from my days as a Ham.
Nice pics, by the way. Let me know how the temp probing comes out. [img]images/icons/smile.gif[/img]
Charles, if you want a 2 C-cell holder for the Arc-LS, I can make one for you. It will be similar to my 1 C-cell holder, but longer to accomodate the 2 cells. Please have a look at the 1-cell holders here: http://www3.sympatico.ca/d.speck/
Here is a runtime graph of the ARC LS head in a 2D Mag with fresh (Dec 2009 expiration) Rayovac Maximum Plus batteries.
The graph looks a little funny because the program crashed for a while at ~ the 10 hour point, and I changed the time measurement frequency at 30 hours. But it should give you an idea of the LUX/time curve.
The LUX measurements listed in the graph were taken with the cheapie LX-101 light meter, with the plastic Mag "lens" in place, and the graph was made with the Radio Shack meter / program that Roy is using in his tests, although my photo sensor is a little more "sophisticated" and filtered to more accurately represent the wavelengths that the human eye sees.
I did take Lux measurements without the Mag "lens", and the light output is about 7% higher than with the lens..... That is fairly efficient compared to a lot of the other "lenses" that I have measured, as most of them have agveraged 10% - 15% of reduction of transmitted light.
Silviron, that's interesting. Did it get hot?? Was the strobing a sign of coming LS failure, or was it due to nearly depleted batteries??
Did you take a look at DSpeck's mods? The cap/adapter/shroud is of particular interest, as this is sort of what I originally had in mind for the Mag-Lite. I did take him up on his offer. [img]images/icons/grin.gif[/img]
His cap would be really good for the LS models that are waterproofed and especially for the LS3 head.
My idea where a max of 6 volts for the LS models that take that amount, would permit the use of the 3 and 4 Cell Mag bodies, with the bonus of the Mag switch to use. Where you need the waterproofness of the Mag setup, particularly for the non-waterproof Arc LS models, your adapter is a perfect solution.
Obviously, usual flashlight use is not to have it on 24/7, but these tests provide valuable data on what is permitted, without damage the Arc LS head or the Mag head.
I am still interested in getting one of your adapters, when you are satisfied with the testing. It would increase my options by one.
This is about extending the versatility of the Arc LS.
I mentioned the heat factor in an earlier post on this thread- It got a little warmer than I would like, but not anything I'd call dangerously hot.
The strobing was because of a nearly depleted battery. The ARC head is just fine
After "resting" the batteries for a few hours, I turned it back on and got another couple of hours of 200-->100 LUX light.
I am familiar with Doug's nice work- We both competed in the challenge to produce the D & C cell LS holders for JonSidneyB (There is a long thread about this about 6 months ago.) which is where those came from. Lacking a lathe at the time, my solution was a different approach though. He also did some machining for me.
I am glad to know it was the batteries. I had 2 CC Extremes in a row. Second one was replacement for original. Both strobed and the batteries were fresh. In the second one, I had a friend take it apart and look at it. He thinks the LED cracked. Both started strobing after about 30 minutes of use. This is why I was very concerned. The extreme is 3 C cells driving a single Nichia LED. Either there were bad ones in the batch, or the current output from 3 C cells was too much.
I am still interested in getting one of your adapters. Even if it is a custom item. Maybe October, as I have to replenish my tobacco supply and bring down my CC balance to allow getting an LS1 rev2 or two, plus replenish lithium AA stocks here.