What's the big deal about the piston lights?

[jzmtl]

My toughs

2. Makes the light more waterproof.

Less resistance. The body of the light is not conducting current when you use a piston. This is really important when the body of a light is Titanium which has poor electrical conduction.

Bill

I find these two claims hard to believe. More waterproof than clickie, no way, in piston you have o ring that moves for either twisting or clicking whereas in clickie no sealing surface does. Less resistance, maybe, maybe not. I don't have any titanium light so can't say about that, but in aluminum bodied lights I doubt it make any significant difference either way.

 

[Flic]

I like them because they are a cool design, great to look at when disassembled and are "neat".

I agree with EngrPaul on his comments. I also do not like PD's because of the lack of tactile feedback. I rarely get an unexpected result from a clickie, but I do regularly get odd responses from PD's. I have in fact sold most of mine (again, kept one because they are great to look at when taken apart).

I've heard folks complain about clickie reliability (not designed to handle the current, etc.) but have yet to have a clickie fail on me. I did buy one Fenix light second hand on CPFMP that had a poor switch, but a $6 replacement solved that and it has not acted up in two years. The cost of a Fenix, even plus two or three switches, is still lower than most PD lights - and they require no more maintenance to stay reliable.

 

[LED-holic]

Wow you guys are still debating this?

The piston lights are great because:
1. they are QUIET. plastic clicky lights are noisy.

2. they are versatile - momentary, twisty, clicky.

3. They are smaller - my D10 is the shortest regular 1AA light I have (my shortest light is the Zebralight H50)

4. Aside from the piston design, the D10 has perfect knurling.

I've used and abused my D10 since they were introduced. They are ROCK solid, as I have more than one.

Great great lights.

If you're obsessive about water intrusion, get a dive rated light. If your fine motor controls are not good, get another light. Otherwise the piston lights are awesome.

PS - my D10 lights have been so perfect that I have nothing to write about any more. I haven't been here in a while because my D10's are the perfect EDC.

 

[jag-engr]

I also do not like PD's because of the lack of tactile feedback. I rarely get an unexpected result from a clickie, but I do regularly get odd responses from PD's.

I would be no means consider NiteCore's Smart PD lights to be tactical lights. The NDI and Extreme, yes, but the D10 and EX10, no. As Flic points out, you don't know for certain what the light will do when it comes on. The D20 may be improved enough to be a tactical light, but I would count on it without more feedback.

I've heard folks complain about clickie reliability (not designed to handle the current, etc.) but have yet to have a clickie fail on me... The cost of a Fenix, even plus two or three switches, is still lower than most PD lights - and they require no more maintenance to stay reliable.

Plus, clickies have been used for some time - you know what you're getting into. I suspect that the Smart PD system may yet prove more reliable, but it hasn't yet.

More waterproof than clickie, no way, in piston you have o ring that moves for either twisting or clicking whereas in clickie no sealing surface does.

I agree with this assessment. I think that many people are getting the waterproof part from the fact that McGizmo's PD lights are waterproof, but I wouldn't count on the NiteCore lights to be waterproof, though they do consistently handle submersion fairly well.



These observations are not criticisms — I really like my EX10 and will soon have a D20. They are definitely more fun than clickies!

 

[EngrPaul]

Wow you guys are still debating this?

The piston lights are great because:
1. they are QUIET. plastic clicky lights are noisy.

2. they are versatile - momentary, twisty, clicky.

3. They are smaller -

AGREED! Good reasons to like PD. :tinfoil:

 

[Marduke]

I think the "big deal" has as much to do with the user interface as the physical design itself. Few (if any) lights give you the unique user interface and combinations possible with NC's line of PD lights.

 

[NutSAK]

I find these two claims hard to believe. More waterproof than clickie, no way, in piston you have o ring that moves for either twisting or clicking whereas in clickie no sealing surface does. Less resistance, maybe, maybe not. I don't have any titanium light so can't say about that, but in aluminum bodied lights I doubt it make any significant difference either way.

That's a good point about the moving orings, but I would think that would only make a difference when there's a large pressure differential between the inside and outside of the body. I think most people assume that the piston system is more waterproof because it has at least one less seal than a typical clickie light (two in the case of Fenix), therefore there's less chance of water intrusion. Considering your point, that may or may not be true.

I consider the PD system more durable because it doesn't contain plastic parts or tiny springs and the electrical contacts are much larger than in a typical clickie. I've had to repair or replace several switches in clickie lights for friends who have dropped them, causing the plastic parts to break or jam. I doubt a NiteCore PD would have any switch failures after experiencing similar drops. This is a guess though, since I haven't put the PD system through any torture tests.

Another benefit for me is that the PD system allows momentary use, but also allows tailstanding without adding any additional length to the light. It is a very versatile system in this manner, because most "tactical" lights with momentary switches have to extend the body to a longer length to accommodate and recess the momentary switch for a tailstand feature.

 

[HKJ]

I doubt a NiteCore PD would have any switch failures after experiencing similar drops. This is a guess though, since I haven't put the PD system through any torture tests.

Try guessing what would happen to a PD system if the lights body gets dented!
This could happen if it hits something hard when dropped (but I am not going to test it with my PD lights ).

 

[NutSAK]

Try guessing what would happen to a PD system if the lights body gets dented!
This could happen if it hits something hard when dropped (but I am not going to test it with my PD lights ).

Another good point, but the specific drops I'm referring to were nowhere near what was required to dent an aluminum body. Those were Fenix lights also, which have a softer aluminum body than the 7075 NiteCore body. My point is, in these particular cases, the light was rendered useless and in the same situation the NiteCore would not have been.

It would be an extreme case indeed if you dropped a NiteCore and it impacted with enough force to dent the side of the body enough to jam the piston. In my experience, the bezel or tail gets dented or nicked in most cases--not the side of the body. In those extreme cases, you may damage the battery enough for operation to cease, and you could easily render a clicky just as useless because of damage to the threads (from ovalizing the body).

Again, I've not tested any of this, so it's all guesswork.

 

[the.Mtn.Man]

I agree. Denting a flashlight would take considerable force of the type that I'm not certain any flashlight could survive.

 

[Kiessling]

No, I wouldn't suggest a brass tube. I'm just saying there isn't a current carrying advantage using a steel tube, considering the body of the flashlight is already aluminum ( a good electrical conductor ). Moreover, using a tube places an additional restriction to heat transfer from the battery to the enviroment. Which means if your battery starts to overheat, it's theoretically a bad situation compared to not having the extra "layer" of insulation.

I don't believe the electrical contact issue is between the steel and the brass. I believe it's between the brass and the board. The force actuating the brass to the board is the force you apply with your finger, minus frictional/suction forces along the tube, minus the spring force under the ring. You can press the piston to the board, but not always have the excess in force necessary to make contact. By plating the brass with gold, you can cut the force required by a factor of about 3.

Another issue is debris. If there is non-conductive material on the board, it takes a lot of force to smash this material down enough that the rest of the board makes contact. Which means any dirt under the ring leads to steeply increased force requirement and intermittent connection through a press stroke (read as multiple actuations). To eliminate this issue, the surface area of contact should be as small as possible, so that contact pressure at any given force is higher. This enables breaking throught the debris barrier with less force and higher reliability.

The electrical advantage lies in the fact that the current uses dedicated surfaces of the piston and not threads (like a lot of the current asian lights do) or other dirty contact point of the body.
AND that means that you can completely anodise the body which can be critical in an environment where corrosion might occur, for example in salty water.

Debris and force ... the inside of the light is sealed, so no debris blicking the piston action. Never had any problem with that. People sometimes so have problems with the momentary action of the piston and need to tweak the spring for a softer activation.

The elimination of the rubber boot gets rid of another weak point.

bernie

P.S.: disclaimer: I only speak for McGizmo lights, I do not know the others

 

[Rothrandir]

I didn't read all of the posts here, and my memory is foggy at best, but I though the piston design was originally developed simply to allow dual-output circuitry to remain inside the head and eliminate the need for any circuitry/resistors in the tailcap? Surely there are pros and cons to such a design, but I believe that was the main or only reason for it?

 

[AvidHiker]

I have to say that one of my favorite features of the PD design is that it allows a tritium marker to be easily installed in the tailcap. In the case of the Nitecores, thanks to the efforts of B@rt and 4sevens, it's quite a substantial marker at that (in terms of size), really nice and very effective as a locator in the dark. I find it really adds to the experience of using the light, not to mention the wow factor when showing it off. Unfortunately, due to sales regulations, its not something that most users will get to enjoy.

As for tactile feedback (that's tactile, not tactical - it should be noted that these are totally unrelated terms), I agree that the feel of a clicky is missed with the PD design, but it hasn't been something that I've found too difficult to get used to (though it does take some adjustment). Plus, it offers the advantages of the commonly sought after "forward clicky" interface, making momentary easily accessable in the otherwise very reliable (but not always the most convenient) twisty design.

I own both a McGizmo PD and a D10 and it should also be noted here that these designs do differ significantly in several functional details, most notably is the absence of Don's "kilroy" contact spring, one of the more interesting aspects of his desing IMO (but not really necessary for a digital interface such as that in the Nitecores). This offers a more advanced momentary function, allowing you to access 2 levels of light in one push, depending on the force applied. I find that the D10 has some issues with momentary (after some unpredictable behavior, itseems to default to high - I'm still a bit inexperienced with this UI however), but it does work.

The marriage of the PD and the digital UI seems to have been pulled off pretty nicely with the Nitecores, but I do sometimes wish it worked a little more like my McGizmo... I suppose I should have a look at the Arc 6 one of these days But its hard to beat Don's KISS philosophy - yes, it can't offer all the wonderful functionality of a digital UI, but there's truly something to be said for a light that can be handed over to a novice without a relatively lengthy lesson in operation (not to mention practice!).

good grief, looks like I'm rambling now... hope I managed to stay on topic for the most part

 

[Melchior]

Terrible lack of design

Most switches should never have any major current passed through them.

Arcing can and indeed happens...

The Ideal switch would be a Power FET transistor with a Reed switch controlled externally with a small magnet. Slide a switch forward and the magnetic field will close the Reed switch and activate the FET that moves the 'real' power.

The only flaw would be the increased cost; (gee a 5 cent switch or 5$ circuit...)
and a poorly designed circuit may drain the battery (sooner than expected).

 

[precisionworks]

how many clicks you must do before it fails? 1.000? 1.000.000?

One of my Surefires (E1L) failed in a week, probably a dozen clicks total. Never yet had a McClicky fail, but that switch by itself costs as much (or more) than some complete lights.