Do p60 drop-ins ever fail?

[waddup]

i dont own any (yet) but they look like completely sealed very strong units (potted)

do they ever fail given the driver and soldering is all in there 'potted'?

obviously the wrong battery v will fry them,

but otherwise are they completely bombproof?

led only.

 

[easilyled]

There is a danger that they could potentially overheat at high currents because the heat-sink is often not making any significant contact with the body of the host.

The contact that is made with the host usually involves only a small area with the rim of the reflector sometimes or with the external springs if they are present.

Therefore when driving a high-powered drop-in at 2.5A or more, it would probably be prudent not to do so for more than about five minutes at a time before throttling down to a lower current if its a multi-stage or switching off for a while if its a single-stage.

If the host is an exotic material like Titanium, then probably all the more reason to be careful since Ti cannot disperse heat as well as Al.

 

[waddup]

seems like a horrible design flaw to me?

if the extrior shape of the dropin and the interior shape of the host were identical then the heat sinking/transfer would be excellent.

i thought that this is the way they are all designed?

only requiring a shim or wrap of aluminum foil or copper tape...?

There is a danger that they could potentially overheat at high currents because the heat-sink is often not making any significant contact with the body of the host.

The contact that is made with the host usually involves only a small area with the rim of the reflector sometimes or with the external springs if they are present.

Therefore when driving a high-powered drop-in at 2.5A or more, it would probably be prudent not to do so for more than about five minutes at a time before throttling down to a lower current if its a multi-stage or switching off for a while if its a single-stage.

If the host is an exotic material like Titanium, then probably all the more reason to be careful since Ti cannot disperse heat as well as Al.

 

[John_Galt]

Not really. Remember, the first P60 lights were incandescents from Surefire. Alot of other companies copied the design, and manufactured similar body styles.

 

[kramer5150]

The P60 was never designed to host LEDs. Incan filaments actually "prefer" to warm up to a steady-state condition from a cold start.

So the LED drop in is merely an adaptation. Surefire realized this shortcoming and designed the P60L to drops output when emitter temps get to a specified level.

So the P60 host is far from an optimal LED host. Its more like a compromise design between two different light sources.

The only potted LED drop ins are the Ando and Malkoff. Everything else is not potted. But they all are hand soldered and hand assembled, so theres going to be some quality variation.

Malkoffs are little brick out-houses... little battle tanks, solid and well made. Heres mine which I took apart to re-build. The one on the right I am re-building into a 1.2A - single cell module. Whats not shown is all the thermal potting compound I had to dig through to get to the bare brass. So these little suckers are WELL made.

I broke my swiss army knife blade trying to pry all the potting compound loose.

The build quality of my cheap DX modules is questionable. I own the 0-100, 5-Mode/Memory, R2-3-18V, Q2-5A, and the now ancient BIN P4-3-18V. My favorite is the 3-4.2V R2, it cuts out at 3V so I run it with my unprotected cells worry free. On all of them I reflow'd the solder around the rim. My DX-MCE also needed the same treatment. But they have been as reliable as any of my best lights, no failures from me.

 

[psychbeat]

There is a danger that they could potentially overheat at high currents because the heat-sink is often not making any significant contact with the body of the host.

The contact that is made with the host usually involves only a small area with the rim of the reflector sometimes or with the external springs if they are present.

Therefore when driving a high-powered drop-in at 2.5A or more, it would probably be prudent not to do so for more than about five minutes at a time before throttling down to a lower current if its a multi-stage or switching off for a while if its a single-stage.

If the host is an exotic material like Titanium, then probably all the more reason to be careful since Ti cannot disperse heat as well as Al.

I run my Nailbender SST50 with an AW 18650 2600
on high til cutoff quite often and have had no problems..
Recently I added some AS-5 to the threads and strips of
aluminum printing plate so it makes better contact in my C-2.
I havent heard of anyone burning up one of these modules - yet.
Im not too worried about it personally... time will tell I guess.

 

[Justin Case]

Depending on design and/or care in assembly, there are several failure modes that immediately come to mind:

- Many drop-ins use a glorified paper ring to insulate the solder pads on the LED's MCPCB from shorting against the underside of the metal reflector. If you crank down on the pill to hard when screwing the pill into the reflector, you can cut through that insulating ring.

- Driver boards themselves are sometimes poorly designed and fry themselves.

- LEDs sometimes are poorly thermally glued to the pill. Heat quickly fries the emitter.

Other probably more rare failure modes include:

- The driver in a typical drop-in is supported around its perimeter by the brass pill. Essentially, it is like a very stiff drum. Use in a weaponlight can produce flexing of the board and eventual failure of solder joints. I've never heard of this actually occurring, so I suspect it is more theoretical than real.

- The solder blobs that ground the driver to the pill may work loose

 

[kramer5150]

- Many drop-ins use a glorified paper ring to insulate the solder pads on the LED's MCPCB from shorting against the underside of the metal reflector. If you crank down on the pill to hard when screwing the pill into the reflector, you can cut through that insulating ring.

This is probably the most common failure mode. Either that or the manufacturer omits the insulator all together. This can create a dead short, +B to -B if the +LED comes in contact with the reflector. Many chinese DC-DC boards directly connect +LED to +B.

I make my own insulators from .01 thick adhesive plastic...

 

[kosPap]

for those not trusting paper isulating dscs there are plastic (white) and black (rubber0 ones sold in Kaidomain..

 

[OceanView]

This can create a dead short, +B to -B if the +LED comes in contact with the reflector.

I know little about electronics. Is this the kind of dead short that can cause imbalanced CR123's to pop? The same kind of *poof* that we used to talk a lot about with CR123 lights running incans bulbs?

Gosh, remember when everyone was so worried about using more than one CR123 in a light for a while because of those stories of their SF's suddenly going *POP*!

 

[csa]

Well, it sure won't be light coming out the front! Interesting discussion of failure modes. The dropins aren't bulletproof, but they do seem to be pretty good.

 

[waddup]

after over a year here and a couple dozen lights, im leaning heavily towards simplifying.

p60 dropins only.

with the choices available i can have single or multiple modes,

from 20-500+ lumens.

lots of very nice dropins always moving thru the marketplace for $40 + or - a few $$

 

[OceanView]

...im leaning heavily towards simplifying...p60 dropins only.

Just a guess, but the incredible choices we have with P60's could eventually dry up. Personally, I think it's a fad that will eventually wane. I just don't think there's enough of a market to support ALL the different brands and models with half a dozen emitter types for much longer.

It wasn't that long ago that there were hardly any choices outside of SF and a handful of other brands, like Wolf-eyes. I forget when the P60 craze took off, but it's certainly a good time to collect all those P60's now.

 

[waddup]

^ good point

 

[Black Rose]

for those not trusting paper isulating dscs there are plastic (white) and black (rubber0 ones sold in Kaidomain..

Are the white ones adhesive?

The KD site has the usual lack of info on these.

I currently make insulating rings out of plastic clamshell packaging.

 

[kramer5150]

I know little about electronics. Is this the kind of dead short that can cause imbalanced CR123's to pop? The same kind of *poof* that we used to talk a lot about with CR123 lights running incans bulbs?

Gosh, remember when everyone was so worried about using more than one CR123 in a light for a while because of those stories of their SF's suddenly going *POP*!

I have no idea... it surely can't be good though. Primaries will vent if they are shorted so its likely the light will explode.

 

[kosPap]

Are the white ones adhesive?

The KD site has the usual lack of info on these.

I currently make insulating rings out of plastic clamshell packaging.

both are...dut not duct tape strong..with time the stik on better...and they are made more forthe bottomof the p reflectors, but it is no harm using one on rach side...the balck ones are smaller and need a hole to be made....

 

[Paul_in_Maryland]

I've been wondering: If an LED is regulated to run on input voltages up to 4.2V, what will happen if I run it at 5V, using three nickel-zinc AA cells? Will it fail in minutes? Hours? After 100 hours instead of 10,000?

 

[Black Rose]

both are...dut not duct tape strong..with time the stik on better...and they are made more forthe bottomof the p reflectors, but it is no harm using one on rach side...the balck ones are smaller and need a hole to be made....

Thanks, ordered some white ones.

I actually prefer them on the bottom of the reflector...makes it easier to swap around reflectors.

 

[Justin Case]

I've been wondering: If an LED is regulated to run on input voltages up to 4.2V, what will happen if I run it at 5V, using three nickel-zinc AA cells? Will it fail in minutes? Hours? After 100 hours instead of 10,000?

It depends on the driver, the LED, the heat sinking, etc etc etc. Why don't you provide more details, such as a photo.

Look at your question this way: I have a magic black box that can run up to X. Is it safe to run it at Y?

Who can tell? You're describing a black box with absolutely zero information on its design, constuction, components, etc.