Maratec AAA won't turn off

[wyager]

But then ........ why are the threads anodized ?

To prevent oxidation.

 

[syncytial]

Finding a good photo of the head contact board in the sea of Maratac/ITP/IlluminaTi posts took a little while.

The best I've come up with are from one of HKJ's exemplary reviews, in Danish. Here is the original, and here is Google's machine translation. There is a good photo of a single mode ITP beside a three mode ITP and a three mode Maratac.

I haven't inspected my other lights yet, but I did see a comment in Selfbuilt's review confirming the threads of the standard AL lights are anodized. I'd agree that this would be so to reduce wear and oxidation, but I still don't see it as necessary for the correct functioning of the light.

<EDIT> I've now checked re: anodizing. All the AL lights I checked have anodized threads, as determined through visual inspection and resistance checks. All the non-AL (SS & Ti) do not, and the bodies and head shells are thus fully conductive. There is no connectivity from the negative contact ring to the shell of the head in any of the lights, so anodizing should have no impact on electrical operation. The anodizing on the threads of the head was missing in a fairly large patch on one of the AL lights, and it functions normally. I suspect the threads and tubes are anodized on lights with anodized external body parts largely because it's easier in production (i.e. cheaper) to remove the anodizing as needed (e.g. on the end of the body where it makes contact with the head's negative contact ring) than to mask off areas that have no impact functionally or aesthetically.


- Syncytial.

 

[Lite_me]

But then ........ why are the threads anodized ?

Maybe plumbers tape on the threads would make a difference for the OP ?

~

The threads(body) to the head(body) play no part in the operation(circuit) of the light. It doesn't matter if there is any contact there or not. Doesn't matter. The only role that the threads play is to move the two halves together so the the body end(rim) can make contact with the outer contact ring on the board inside the head. That's where the circuit is made.

 

[pushcart]

I had a similar issue with an ITP A3 SS (essentially the same light) that started to stay on all the time, after a month or so of normal, but fussy operation.

When I looked into the head with good lighting and a bit of magnification, I saw a small "whisker" of copper that was bridging the ring on the board to the shell of the head. A little delicate work with a "dental" pick, followed by a light sanding of the end of the tube, a thorough cleaning and lube and it's been good for more than six months. It had been fussy even before deciding to stay on full time, but after maintenance it's been entirely reliable. It rides in a shirt or pants pocket every day.


- Syncytial.

On inspection, the contact ring was very close to the shell. After cleaning the ring with isopropyl the problem is gone. Maybe a combination of shell/ring contact and loss of anodizing. Thanks all for the suggestions.

 

[TooManyGizmos]

OK ..... I don't have one ..... so I was just asking .

Being a twistie , I could not imagine any other possible point for continuity once it was unscrewed 1/2 turn . He said unscrewing it would not turn it off.

If negative path can only flow back to the head thru the bare end of battery tube contacting the neg. circuit board ring - then how can it light when that path is broken .......... without continuity thru the threads , and also the neg. contact ring shorted to the head body .... completing the path ?

Thread continuity WOULD matter ...if his neg. pill contact ring were touching the threads inside the head .

Maybe the pill was moving with the batt. tube when unscrewing it ?

Oh well ...... glad he got it fixed ... if he really did ?

The threads(body) to the head(body) play no part in the operation(circuit) of the light. It doesn't matter if there is any contact there or not. Doesn't matter. The only role that the threads play is to move the two halves together so the the body end(rim) can make contact with the outer contact ring on the board inside the head. That's where the circuit is made.

 

[wyager]

What COULD have happened is that the anodizing DID get worn down AND the copper ring was shorting to the aluminum of the head. That would have kept the circuit going.

 

[TooManyGizmos]

~

That's exactly what I'm saying.

Not the normal operation .... but a secondary circuit .... once TWO other failures have happened and worked together as a circuit .

~

 

[march.brown]

I have a "Morcol" glass fibre burnishing brush that is great for cleaning into the head end of torches ... Just poke it down where it's needed and twist it ... Really cleans things up well.
.

 

[Zendude]

~

That's exactly what I'm saying.

Not the normal operation .... but a secondary circuit .... once TWO other failures have happened and worked together as a circuit .

~

I think what he's saying is that the pill is electrically isolated. It would have to be to work in a SS/Ti light. It's the same pill for either the Al or the SS. Even if the ano wore off it shouldn't conduct.

 

[TooManyGizmos]

Well .......... something did ....... too well !

It wouldn't turn off .


What do you say caused it ?

~

 

[wyager]

I think what he's saying is that the pill is electrically isolated. It would have to be to work in a SS/Ti light. It's the same pill for either the Al or the SS. Even if the ano wore off it shouldn't conduct.

The pill is electrically isolated by about half a millimeter. If it got bumped or a sliver of metal shorted the pill and the head it would keep the circuit going. It could also be a short inside the pill, one that you can't see, as they have to jam everything in that really small space.

 

[Zendude]

Well .......... something did ....... too well !

It wouldn't turn off .


What do you say caused it ?

~

My guess is we are missing a critical piece of information.:)

Did the OP state it was an Al case?:thinking:

I agree with your thinking, I just find it improbable that the ano wore off both threading surfaces, inside the head right next to the negative contact AND a metal bur bridged the gap.:faint:

Note that I said "improbable" and not "impossible". :tinfoil:

 

[pushcart]

My guess is we are missing a critical piece of information.:)

Did the OP state it was an Al case?:thinking:

I agree with your thinking, I just find it improbable that the ano wore off both threading surfaces, inside the head right next to the negative contact AND a metal bur bridged the gap.:faint:

Note that I said "improbable" and not "impossible". :tinfoil:

I'm the OP. Mine is SS. I assume the SS is conductive as shipped.

 

[gunga]

The SS or Ti (Illuminati) can turn on and stay on if you get a conducting path between the body and the circuit board. This can be due to a bit of metal coming off the circuit board and getting stuck between the board and the shell. You can run a small blade or screwdriver in between to ensure there is no conduction between the body and the edge of the circuit board. You can check this by using an ohm-meter and checking for resistance bewteen the edge of the board and the shell. You should have an open circuit, if not, that is why it stays on. I've had this happen before in a ti Mini AA, you need to clear out any connection betweem the 2.

You can also swap out the area with a alcohol soaked q-tip afterwards too.

G'luck!

 

[TooManyGizmos]

~

pushcart fixed it by cleaning it (post 24) ....... all better now .

 

[syncytial]

I'm the OP. Mine is SS. I assume the SS is conductive as shipped.

Yup.

I think enough of us have beaten this poor horse that it's well and truly dead by now.

(Did anyone actually read the posts?) <-- Rhetorical question, no response required. ;)

:dedhorse:

 

[TooManyGizmos]

~

Didn't BEAT it to death .... we were just being analytical as to what could have caused it .

That's what we do !

And MOST of us previous posters DID read prior posts .

~

 

[leukos]

What kind of lube are you using? On the Maratac (as well as some other twisty lights), you have to use non-conductive lube, otherwise the lube will continue to complete the circuit even though the head is not tightened down all the way. If you are using the conductive lube, it will eventually work its way down to where you can no longer clean it with alcohol and your light will constantly be on.

 

[TooManyGizmos]

~

So... you mean "blobbed-up" lube between the threads of the head , crossing the gap , to the neg. contact ring on the pill .

Or maybe even causing constant continuity between the neg. contact ring to the polished end of the battery tube ? (through lube)..... no matter how far the tube is un-screwed ?

Do you suppose the lube is really THAT conductive ?

Wouldn't it have higher resistance than that ?

~

 

[march.brown]

I have several iTP torches which are virtually identical to the Maratac design.

The open end (rim) of the torch body has to make contact with a ring in the head to turn the torch on ... It doesn't matter if there is electrical continuity between the head and the body ... The rim of the body has to be in contact with the ring ... The only way for the torch to stay on permanently is for a metal "hair" to bridge between the head and this ring.

As previously stated by gunga , it should be possible to put an ohmeter between this ring and the head to look for a short circuit.

It should be possible to see any metal hair using a loup or magnifying glass by looking at the ring.

I doubt whether any lubricant would have a low enough resistance to turn the light on ... It might possibly slowly drain the battery , but it would have to be virtually a full short to make the torch light up fully.
.