SOLVED: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

EngrPaul

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SOLVED: Go to post #17 below.
When I pocket my Nitecore D20 or put it in my laptop case, it's often ON when I pull it out.:wtf:

I couldn't figure out what was going on.

Then once while I had it out, I put it down lightly on it's tail side, and it came on.

No, my tail button doesn't stick up above the bottom. Instead, it seems a slight bump to the back side of the light causes the light to come on.

Oddly enough, a similar bump does not turn it back off. :thinking:

I figured out that the weight of the batteries is significant vs. the force of the spring. A bump causes the batteries to momentarily move backwards away from the (+) contact.

I suggest a re-program is in order. If an interrruption only lasts a few milliseconds, the light shouldn't come on.

Anybody else have the same experience?
 
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snowlover91

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

When I pocket my Nitecore D20 or put it in my laptop case, it's often ON when I pull it out.:wtf:

I couldn't figure out what was going on.

Then once while I had it out, I put it down lightly on it's tail side, and it came on.

No, my tail button doesn't stick up above the bottom. Instead, it seems a slight bump to the back side of the light causes the light to come on.

Oddly enough, a similar bump does not turn it back off. :thinking:

I figured out that the weight of the batteries is significant vs. the force of the spring. A bump causes the batteries to momentarily move backwards away from the (+) contact.

I suggest a re-program is in order. If an interrruption only lasts a few milliseconds, the light shouldn't come on.

Anybody else have the same experience?

Mine doesn't do that, mine only turns on when I mash the button. I suggest you contact where you bought it from and get a replacement. If you bought it from 4seven's they will get everything right for you. Hope you figure it out, the PD lights are great as long as you get a good one. Yes, there are "duds" out there, but it is well worth it IMHO once you get one that functions properly.
 

Alan_P

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

I have a D10 and an E10. The instructions that came with the light suggest twisting the light off whenever it might go on accidentally. The manufacturer is aware of this charasteristic of these flashlights.
 

f22shift

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

this is kind of similar to the lf5xt problem and they reprogram not to respond with a short connection/disconnection like you suggested.
 

EngrPaul

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

The D20 has 2X the battery weight of the D10 and EX10.

I can make the D10 come on by hitting the tail on the palm of my hand, but it's never come on by accident like the D20 does.

Another solution I see manufacturers using is a spring at the (+) terminal (For instance, a change Dereelight made to the C2H recently).
 

netprince

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

Mine comes on in my pocket a lot too. I pulled it out the other day and the batteries were completely used up. I started unscrewing the head so its in tactical push-button mode...

I would love to see it smart enough not to come on after the batteries bounce...
 

EngrPaul

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

Thanks for letting me know I'm not the only one ;)

I look for a light I carry to be reliable and good runtime. When a light comes on by itself in your pocket and is dead when you need it, it's not exactly reliable, unless accustomed to using it as a twisty. But then, what good is the PD system if you have to twist it all the time?

Mine comes on in my pocket a lot too. I pulled it out the other day and the batteries were completely used up. I started unscrewing the head so its in tactical push-button mode...

I would love to see it smart enough not to come on after the batteries bounce...
 

Marduke

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

Try backing the head off 1/8 of a turn.
 

swrdply400mrelay

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

yea i have the same problem too

i ended up just stretching out the spring in the piston, and don't have the problem anymore

AW 14500s seem to be a bit longer than the standard AA, and i think that has helped a little too
 

Marduke

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

yea i have the same problem too

i ended up just stretching out the spring in the piston, and don't have the problem anymore

AW 14500s seem to be a bit longer than the standard AA, and i think that has helped a little too

I hope you're not using 14500's in the D20.... :poof:
 

Axion

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

Try backing the head off 1/8 of a turn.

This. My EX-10 will bump on in clicky mode, but leaving it in momentary mode when it's in your pocket solves the problem.
 

Closet_Flashaholic

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

1) I also ran into a exhausted battery, a couple of times with the D10 in my pocket. I now carry it momentary mode, I haven't had a problem for the last 3 months..

2) If you are very fast (with your thumb), you can actually use the short-cuts even in momentary mode.. I can do it reliably now, so I set it low momentary and that way if it gets left on, it won't generate too much heat and high is just a press-press-hold away - even in momentary mode. - Try it.

3) Another problem that I ran into was that even in momentary mode, I had the lanyard clip twist and jam in such a way that it actually depressed the button and left the light on - even in momentary mode. - How weird is that? This only happened once, but I keep an eye out for this condition.
 

Marduke

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

I didn't really mean to put it in momentary. On my D20 I can back it off 1/8 of a turn and still click for constant on, but the travel is longer and it gives a different tactile feedback. Twisted any further and it works like a true 2-stage piston, with a full stroke press causing the light to ramp.
 

Lite_me

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

1) I also ran into a exhausted battery, a couple of times with the D10 in my pocket. I now carry it momentary mode, I haven't had a problem for the last 3 months..
I just had my D10 come on in my pocket tonight. It was not clipped but sitting down in my in my deeep watch pocket in my jeans. I was in the car and when I had reached my destination and needed it for something, I found it on when I pulled it out. I'm gonna have to start lockin it out or set it on low from now on. :shakehead

Oh, and I checked my D20 and it will bump on also. I did notice though that if you leave it off for a short time, you have to tap/jar it harder to get it to light. That doesn't help at all though cause that's the state it'll be in most of the time anyway.
 

brucec

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

I think this is almost certainly a sticky piston spring issue. This is a problem inherent to the Nitecore PD design, as opposed to the original McGizmo or Arc6 PD. What is happening is that the piston ring is not fully springing back out. Then when the light receives a slight bump, the ring springs back out and makes contact with the piston sleeve, thereby turning it on. It doesn't turn back off because it only turns back off when you back out the piston sleeve even more or you click off. For people that carry their lights in momentary mode, be careful. Depending on how much travel is left when the piston ring sticks, you may think you are in momentary mode, but may actually be in range of the piston ring when it desides to spring back out.

Anyway, try opening up the piston ring gap with a small screwdriver or knife. I don't have a D20, but on my EX10s I disassembled the entire head assembly and stretched the piston spring as well as lubed it. Seems to have fixed the problem, but I hope Nitecore seriously looks into this fundamental design flaw.

When I pocket my Nitecore D20 or put it in my laptop case, it's often ON when I pull it out.:wtf:

I couldn't figure out what was going on.

Then once while I had it out, I put it down lightly on it's tail side, and it came on.

No, my tail button doesn't stick up above the bottom. Instead, it seems a slight bump to the back side of the light causes the light to come on.

Oddly enough, a similar bump does not turn it back off. :thinking:

I figured out that the weight of the batteries is significant vs. the force of the spring. A bump causes the batteries to momentarily move backwards away from the (+) contact.

I suggest a re-program is in order. If an interrruption only lasts a few milliseconds, the light shouldn't come on.

Anybody else have the same experience?
 

EngrPaul

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I have completely solved the problem by adding a skinny little spring that has a starting diameter slightly less than the (+) post. It hangs onto the post during battery changes, and when cells are installed it prevents the cells from losing contact when they momentarily pull away during a bump.

This particular size spring is hard to find. Any bigger, and there is a risk shorting to the circuitry.

Twisty and momentary modes still work the same.

Can you do better? :nana: If so, let's see!

IMG_2850.jpg


IMG_2849.jpg
 
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StandardBattery

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Interesting... Good Solution.

I have a D20 mainly because it was cheap and I got rid of the D10, but still wanted to have PD light. I'm running 2 Eneloop in mine and even a really hard jar is not triggering it on. I'm not sure if the cells make a difference due to their weight or precise length.
 

2manybikes

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

I have a D10 and an E10. The instructions that came with the light suggest twisting the light off whenever it might go on accidentally. The manufacturer is aware of this charasteristic of these flashlights.

:thumbsup:

The D 20 even has been changed so that the lock out works better when unscrewed a little, the piston cannot travel as far and will not make the light go on. Just Like a lock out on clickies. They engineered and manufactured an improvement. Not a small thing.
Why don't people read? There is no "problem".

From selfbuilt's review here in CPF........

The purpose of this re-design quickly becomes apparent – the light has a fully functioning tailcap lock-out feature now. :thumbsup: Previously, you could partially lock-out the light by significantly unscrewing the head – making it harder for the piston to engage. But this was not a true lock-out – the piston drive could always be engaged with enough force. Now, the piston can only travel so far up the battery tube, so once you unscrew the head pass a certain point, the light cannot be engaged. Well done.
 
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EngrPaul

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Re: Nitecore D20 turns itself on with slightest bump (not-so-smart PD)

"If you read", a lockout is used to prevent accidental pressing of the piston. Lockouts on flashlights are used to overcome accidental pressing of the on/off button.

A lockout is NOT supposed to be used to overcome bad design of the flashlight! There IS a problem!

:thumbsup:

Why don't people read? There is no "problem".

From selfbuilt's review here in CPF........

The purpose of this re-design quickly becomes apparent – the light has a fully functioning tailcap lock-out feature now. :thumbsup: Previously, you could partially lock-out the light by significantly unscrewing the head – making it harder for the piston to engage. But this was not a true lock-out – the piston drive could always be engaged with enough force. Now, the piston can only travel so far up the battery tube, so once you unscrew the head pass a certain point, the light cannot be engaged. Well done.
 
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