Heads up -- 9V Pak-Lite now has a warm white option...

[scout24]

That's a Yuji mod beside a stock cool white Pak-lite. You do lose a bit of throw, but it's still good for 50 feet plus outdoors, and the low is oh-so-soft and floody. Carrot-PM incoming.

 

[ZMZ67]

Looks like the Yujis do a great job in pure flood department, more of an even flood than the 4K judging from your pics. I suspect the 4K will throw a bit more than the Yuji mod just like the original. I like the more neutral tint of the 4K better(based on the pics) but I don't have any actual Yujis for side by side comparison. Doubtful that the folks at Pak-lite would consider offering a 3K model but your mod illustrates a possible option for the true warm fans out there.

 

[wacbzz]

That's a Yuji mod beside a stock cool white Pak-lite. You do lose a bit of throw, but it's still good for 50 feet plus outdoors, and the low is oh-so-soft and floody. Carrot-PM incoming.

I've got three of the 4K lights...along with the photon freedom, I'd like to try this mod.

How did you get into the PK-Lite head to swap in the Yujis?

 

[scout24]

The paklite board seems to be held in the plastic housing with a dab of superglue on both of the long sides. I scored that seam a few times with an exacto knife, and pried the long sides of the opening gently apart, and then the short sides, alternating until I heard the glue let go. Just with thumbs, nothing crazy. A bit more with the exacto, some gentle lifting with an eyeglass screwdriver, and out came the board. Emitters are soldered and hot glued in place. The openings in the housing need to be widened ever so slighgly for the Yuji's to fit.

 

[lampeDépêche]

Their website is advertising a 15% discount for the next few days. That brings the new Warm White down under $17.

Oh--and moderators, feel free to pull this if I am out of line in posting it. No, I don't work for them or have any relationship with them, except I buy their products now and then and I used to live in Oregon....

 

[archimedes]

....
Oh--and moderators, feel free to pull this if I am out of line in posting it. No, I don't work for them or have any relationship with them, except I buy their products now and then and I used to live in Oregon....

No direct link, no connection with them ... you're fine

 

[carrot]

Their website is advertising a 15% discount for the next few days. That brings the new Warm White down under $17.

Oh--and moderators, feel free to pull this if I am out of line in posting it. No, I don't work for them or have any relationship with them, except I buy their products now and then and I used to live in Oregon....

That may just be reason enough to pick up another. In my uses of the 4K model the past couple of days I've been really impressed at just how much of an improvement they are over the standard angry blues.

They also make a heck of a tail stand light at home and I already know they'll surpass my lanterns for lightweight backpacking.

 

[lampeDépêche]

small note of caution on their 9v lithium cells.

They now carry the "Forte" line of 9v lithiums, which are based on lithium/thionyl chloride chemistry:

https://whforte.en.alibaba.com/product/818653969-218200456/1200mAh_9_volt_Lithium_battery_ER9V.html

Great thing about thionyl chloride chemistry: it has almost twice the energy density per weight of ordinary lithium chemistry. That's why this 9v is rated at 1200mah, instead of the 700mah that e.g. Eveready's 9v lithium carries.

Bad thing about thionyl chloride chemistry: they are more hazardous than standard lithium batteries.

from wiki:https://en.wikipedia.org/wiki/Lithium_battery#Chemistries

"High cost and safety concerns limit use in civilian applications. Can explode when shorted. Underwriters Laboratories require trained technician for replacement of these batteries. Hazardous waste, Class 9 Hazmat shipment.[13]​ Not used for consumer or general-purpose batteries....Lithium batteries can provide extremely high currents and can discharge very rapidly when short-circuited. Although this is useful in applications where high currents are required, a too-rapid discharge of a lithium battery can result in overheating of the battery, rupture, and even an explosion. Lithium-thionyl chloride batteries are particularly susceptible to this type of discharge."

I bought one from them, not knowing the chemistry, and I am going to use it in a fixed, stable location in my house. I would not want to carry it in a kit where it could get crushed or shorted--I would rather use the more stable, manganese dioxide chemistry. The "Ultralife" line also claims 1200mah, and uses the manganese dioxide chemistry, so that's what I will put in my travel kit.

Now, I am not an expert on this stuff, so everyone should feel free to correct me and get better info out there. But that's how it looks to me.

 

[hap124]

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[lampeDépêche]

I wish they would list lumen specs on the site and I hate it when a company leaves out that crucial info. Their super...ultra etc designations don't tell me useful info and I am seeing everywhere from 10-14 to 70-90 lumens on high depending on the review/search result.

I don't know the official numbers, and I agree that Pak-lite should just publicize them (ideally in the form of runtime vs. output curves of the sort we are used to on this forum).

That said, I think that 15 lumens on high is a reasonable guess, and 70-90 is ridiculous. No way.

And a fair estimate for the low would be about 1-2 lumens.

 

[hap124]

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[ZMZ67]

I agree with lampeDepeche ,70-90 lumens from a Pak-lite is ridiculous. Not sure how that reviewer came up with those numbers but the 15 lumen estimate is more in line with what I see based on the rated output of some of my other lights.

 

[lampeDépêche]

Well, the reviewer in hap124's link says:

"Although PakLilte does not provide Lumen specs, the tiny PakLite light delivers around 70-90 Lumens on high when comparing it to other similar Lumen spec'ed lights I own."

So the reviewer had a light rated at 70-90 on high, and tried to gauge the Pak-lite output by using it for a visual comparison. But as all of us here know, that is a *very* imprecise way to measure lumens. Some people, e.g., just look at intensity in the hotspot. Very few people understand the log scale. So the 70 lumens was just a bad guess.

Plus, I'm pretty sure that reviewer's 70 lumen light needed fresher batteries.

 

[carrot]

I measured the Pak Lite to be about 36-40mA depending on sample and 1.2mA on low. More electrically oriented minds can probably form a reasonable guess from there.

I think it's fair to assume that the LEDs are Nichia GS for the normal model?

 

[lampeDépêche]

I measured the Pak Lite to be about 36-40mA depending on sample and 1.2mA on low. More electrically oriented minds can probably form a reasonable guess from there.

Those are "tailcap" measurements, right? i.e. putting an ammeter in between the terminal of the battery and the terminal of the light? So the milliwatts into the circuit are nominal 9 times that?

I don't have the electronics chops to convert that into lumens, but it does roughly check out with the run-times that Pak-Lite claims, checked against the capacity of a Duracell coppertop. That has about 600mah, and they claim 600 hours on low, so they are saying it will average 1ma through the course of its life. If you read 1.2ma on a relatively full battery, then that would account for the discrepancy: it will start at 1.2ma, and drop throughout the 600 hours to average 1ma for the course.

I suspect the same is going to apply, but even more drastically, in the case of their high mode. They claim 30 hours, and you cannot get 30 hours of 36ma out of a battery that contains 600mah.

Worse than that--it contains 600mah only if used in *very* low current circuits, i.e. 1ma or so. The coppertop datasheet shows that if you hook it up to a constant 10ma drain, it will get around 60 hours. So my guess is that the high-setting does drop quite a lot from that initial 36-40ma draw in order to get 60 hours.

Objection: "when I turn on my Pak-lite, even after the battery has been used quite a bit, it still delivers about the same output. It does not *seem* like the light gets dimmer over the life of the battery."

Reply: alkalines show strong recovery in intermittent use. If you turn it on one night for a few minutes, and turn it on the next night for a few more, then the battery will have recovered enough to give something close to full power the next night.

But there's no free lunch. Intermittent use may give you higher current each time you use it, but you are *not* going to get 60 hours worth of higher-current use out of it. Whereas, if you put in a fresh battery and leave it on for 60 hours, you would probably see a marked drop-off in output throughout the 60 hour period. Remember--they can claim run-times out until the light drops below 10% of initial value, so about 1.5 lumens.

Which checks out with another (anec)data point: I can tell when one of my batteries is basically dead, when the output on high is the same as the output on low.

 

[badbs101]

Ordered mine today with the lithium battery. Overpriced light? Yup. Essential? Yup. I'm a sucker for a warm or neutral light and Paklite was definitely due for an upgrade from their angry blue LEDs.

I even ordered one of those new warm Maglite Solitaires. I love that light and it would be perfect with a clicky tail switch...

 

[carrot]

Those are "tailcap" measurements, right? i.e. putting an ammeter in between the terminal of the battery and the terminal of the light? So the milliwatts into the circuit are nominal 9 times that?

I don't have the electronics chops to convert that into lumens, but it does roughly check out with the run-times that Pak-Lite claims, checked against the capacity of a Duracell coppertop. That has about 600mah, and they claim 600 hours on low, so they are saying it will average 1ma through the course of its life. If you read 1.2ma on a relatively full battery, then that would account for the discrepancy: it will start at 1.2ma, and drop throughout the 600 hours to average 1ma for the course.

[snip!]

Which checks out with another (anec)data point: I can tell when one of my batteries is basically dead, when the output on high is the same as the output on low.

Thanks for doing the math on that one. I suspected as much because it's clearly a simple circuit. I think we often forget about the long tail behavior of alkalines because we are so focused on batteries that perform at higher current.

I think that despite- nay- owing to- the simplicity these lights are indispensable. The inherent voltage sag of alkalines, the long runtime of a circuit that sips a very reasonable current, the compactness of the light, and the tailstanding, anti-roll battery shape make these terrifically usable lights.

Case in point, I recently vacationed on a cruise liner and with no lights on, an interior cabin is very, very dark. Dark to the point of being disorienting, even! The Pak-Lite would have been ideal as a bedside night light, not too bright but surprisingly more than adequate light; its glow-in-the-dark body would have been very easy to locate as well.

For camping and backpacking- the Pak Lite is ideal as a tent locator beacon, a mini lantern, and a backup flashlight. Too often have I fallen asleep to a lit headlamp or lantern only to find it dead in the morning; by my own fault or a result of lending it to a friend. Many of our more powerful lights have a moonlight or long runtime mode as well, but it's of no use if it was left in a higher output setting. With even the high output of the Pak-Lite being a relatively low current, there's adequate assurance that the light will be usable for weeks.

I just need to find an adequate diffuser to make it an ideal lantern. In a short time I have gone from none to five of them.

 

[lampeDépêche]

I just need to find an adequate diffuser to make it an ideal lantern. In a short time I have gone from none to five of them.

Good idea! I wonder whether a latex or clear-ish vinyl glove would work well for this. Snip off a length of the thumb, for instance, and then slide it over the top with a bit of air trapped in the top to make it dome out. It could even make the light more waterproof if it was a tight fit.

I think this is more likely to work than trying to find a tube of lip-balm with a rectangular cap.

(Another case in point: I was staying in a hostel the last few days where the shower stalls were tiny and dark, and once you stepped out of them you were in an ante-room that was tiny, dark and closed with an opaque door. I am not much prone to claustrophobia, but this whole set-up made me distinctly uncomfortable throughout my first shower. The next day, I brought in one of my Zebralights and set it on a shelf in the shower, shining on medium. It really, really helped. Not only having more light on, but also knowing that I would have light if other lights went out. Now, a regular Pak-lite would not have been water-proof enough for this job. But maybe with a latex thumb snugged down on it, it would have worked. Otherwise, on this trip my Pak-lite stayed in my kit, undeployed.)

 

[carrot]

Good idea! I wonder whether a latex or clear-ish vinyl glove would work well for this. Snip off a length of the thumb, for instance, and then slide it over the top with a bit of air trapped in the top to make it dome out. It could even make the light more waterproof if it was a tight fit.

I think this is more likely to work than trying to find a tube of lip-balm with a rectangular cap.

I like this low tech solution. However, I went to bed dreaming up how to spec and shape a 3d-printed lampshade and/or right-angle reflector, the first for camping tables and the second for an improved be-seen bike light.

 

[novice]

This thread mentioning that there is a warm version of the PAK-lite had me sitting on the fence, but the fact that the redoubtable (in a good sense) Carrot now has five is pushing me towards another I-don't-really-need-this purchase. I have a now-defunct PALight that I have not used much, and I would like to compare the two. I also didn't know until recently (silly me) that there are lithium primary 9v cells. I have a small number of dear friends that I have tried to gift with different types of lights on appropriate occasions, and I may have to get them some of these, too.