Arc Grey R2K HD

[tylerdurden]

Well, I finally replaced the unknown LD on my grey kit with a R2K HD. I'm wondering why I waited so long.

It's a bit hard to tell, but the emitter is a tiny bit off-center. How are you guys out there centering the Luxeons on these boards? I just screwed the bezel down on top of it.

Against the miniminimag/madmax+R2H:

I put a slightly used battery in the MMM/MM+R2H, hoping to show the centering differences more than the brightness differnce. As you can see, the color in the two lights is the same (the color shown in the photos is not correct, but since the white balance is equally off for both lights, you can make comparisons between the two).

Bonus shots of the two lights:

 

[lambda]

Very nice!

That looks like a little light cannon.

Centering Luxeons is a black art unless you spin the flashlight. I have the luxury of a lathe, so I can chuck things in it (at lowest speed!) and nudge things dead center.

I've tried using the 'tighten the lens down' method and jigs and fixtures, but nothing can beat a steady rotation. An old LP phonograph could probably be made into a good Luxeon centering tool.

So, what are the nice ring mounts for?

 

[tylerdurden]

The ring mounts? Are you talking about the jewler's vice? I just got it about a week ago from micromark.com, and it's very helpful. It's just the right size for holding converter boards while soldering. It also was perfect for holding the grey up to the same hieght as the miniminimag.

I think I need a better camera. This Creative webcam3 was cheap, but the quality is really crappy.

 

[oldeng95]

that looks great, but where did u get those parts?
a grey Arc???
and a R2K????
Who is your soucres, hahahahh
also, how much brighter did it get from an orignal arc
got pics??

 

[Chief_Wiggum]

Someone on this forum turned me on to using a little epoxy on the emitter.

I tried it on one of the X5T conversions I'm doing and it works pretty well.

Just put a tiny bead of epoxy on the emitter, set the optic down on it, and hold a sheet of paper above the beam to get it exactly on center.

Of course this only works if you can power the board before final assembly.

But it works great. Just a tiny bit of epoxy is all that's needed.

 

[gyverpete]

That's not the standard greykit circuitboard/heatsink slug. It certainly doesn't look like mine. Did you put it together or did you have it custom made? Where did you get the R2K?


The luxeons that came with my greykit were greenies, so I put a Q3J in it instead and it's much brighter and whiter than my LSL hybrid. I like the high dome better too. I centered mine by applying artic alumina paste then soldering the tabs with the emitter approx. centered by eye, then twisted the bezel/optic on and looked at the beam. It was off a bit so I marked the side it was favoring on the body, unscrewed the bezel carefully so as not to rotate the board, and nudged the emitter away from the marked side while pushing down on it to squish the paste. It took two tries to get it perfect.

 

[tylerdurden]

I bought the grey already assembled (from shiftd, IIRC). I stripped the HA off of the bezel with lye, but haven't made any other changes. This is the only grey kit I've ever seen in person, so I don't know how it differs from others. I got the R2K from dat2zip.

I don't have any other arc to compare it to, and I didn't take any beamshots before removing the LD emitter.

 

[shiftd]

I bought the circuit originally from YCLO. I believe it is the newer version of the circuit (rev 2, perhaps?)
Btw, nice mod you got there, TD. /ubbthreads/images/graemlins/thumbsup.gif

oh ya, people uses mcflood to center the lux. But if you get just a slight discenter, then Mcflood prolly would not be much of help to you.

 

[gyverpete]

The original looks like this:

(This is a portion of a pic posted by JohnG in an old greykit thread. The only part that is not as originally designed by ARC is the large shottky diode on the right side, which is normally a small surface mount diode, though the larger one works and fits. Most greykits didn't incude the diode.)

Yours was either custom made (and may be better than the original since they went through the trouble of making it), or as shiftd says, it could be a newer version by ARC.

 

[tylerdurden]

Re: emitter centering, it's close enough to center that I can only tell when I point it at a wall or other flat surface with consistent color, so I'm not going to worry about it (at least, not until I replace it with a S bin /ubbthreads/images/graemlins/cool.gif ).

 

[z3r0]

As far as i know, the only difference between an R2K and R2L is the Vf right? According to a pdf file posted (can't remember who), the R2L can take up to 3.99v. Which one would be more desireable, higher or lower Vf?

 

[Chop]

You definitely want lower Vf on a regulated light for longer runtimes. The trouble is that you can't count on binning. I have an R2K in a KL1 running at 815mA and a Q3J running in a KL1 at 795mA and the KL1 with the R2K consistently gets 10-15 minutes more of runtime. Go figure. /ubbthreads/images/graemlins/icon3.gif

 

[Klaus]

The circuit out of this flashlight is the "old" rev1 voltage controlled one - exactly what yclo was buying from Peter in an auction and selling since. The "original" grey kits did include the "newer" Dat2zip designed current controlled rev2 circuit. As I assembled/disassembled ARC flashlights with both circuits (and swapped emitters on both too) I´m sure on this.

Talking about voltage binning - as the old rev 1 circuit obviously prefers lower Vf emitters and not only for runtime and I was re-viving an old rev1 ARC LS with an HD for it I had been testing quite some Q3K and Q3J and other emitters too for a while now - the lowest Vf LS I have on hand is still one of the Q3K which SHOULD have a higher Vf.

Klaus

 

[tylerdurden]

Klaus, when you say "the circuit out of this flashlight" do you mean my kit at the top of the page?

In any case, what are the differences between the two circuits?

 

[z3r0]

Although having a higher Vf might not be such a bad idea (if the following is true). If in the future, Li-ion battery packs came out that are able to fit in the arc, I could comfortably use them in an Arc because a high Vf of the led. At such a high voltage power source, doesn't the the circuit in the arc let the battery direct drive the led until the voltage drops a little? If so, having a higher Vf led may be nice, although, like Chop said, you cant' count on the binnings.

 

[Klaus]

z3r0 - you are right in regards to high Vf and LiIons IMO.

Tylerdurden - yup - I was referring to your original post, yours is the original rev 1 circuit easily detectable by the double setup of the chips used - I *think* that PG used kind of a double AAA circuit for this first LS shot.

As to the differences - lots of opinions in the early days of the hybrid/rev2 circuits on the pros and cons - actually I like both - I´ll try to give a short summary:

rev1 - runs down to 0.x V so it can be nicely used with 1 cell only - voltage controlled and therefore "semi-regulated" - the higher the Vin the higher the Vout and current - I *think* it was set to sub-350ma levels but this will depend on the Vf of the actual LS used.

rev2 - dat2zip designed circuit using the LT chip he is also using in the BB? series AFAIR - doesn´t support 1 cell operation as well as the rev 1 circuit - current controlled "fully regulated" and therefor independent of the Vf of the LS used - besides lower Vf will give longer runtime and vice-versa - claimed better efficiency than the rev 1 circuit.

Klaus

 

[tylerdurden]

Ah, yes, I must have the rev1 then, because I have used this board with 1xAA and it does a pretty decent job, though it isn't as good as 1x123.

Thanks for the details.