Anatomy of a forward clickie (photos) more added 1-29-08

[srvctec]

I've always wondered exactly how a forward clicky switch (momentary on) worked. I have taken apart a reverse clicky (see here) and it works similar to the inside of a ball point pen, much as I suspected. I have never had the opportunity to dissect a forward clicky, that is, until tonight.

The photos below are from the switch in my NiteCore Defender Infinity, my EDC since the day I got it and my favorite light up to this point. A couple of weeks ago, my switch started intermittently sticking in the on position, so EdgeTac sent me a replacement switch- gotta love their customer service- it's top-notch. I got the replacement switch today and decided to take apart the defective one, partly to see what was the cause of the sticking and also to see how a forward clicky works (I'm the type of person that just has to know how everything works).



The defective switch in all its glory.




Bottom of the switch with the legs folded under for soldering onto the circuit board. I wasn't crazy about this method, so I cut the legs off before soldering my new switch back onto the board.




Top of the switch removed with insides placed exactly how they are with cover on. The clicky parts look a lot like a ball point pen inside as well.




Another view.




Closeup of the inside of the bottom piece. These are the contacts that get closed by the spring supported metal disk providing momentary on until the switch is clicked into the on position.




Individual parts arranged in the correct order of an assembled switch.




I couldn't find out what was causing the sticking, but my light works perfectly again with the new switch installed. And a bonus of the little glitch with my light- I get to see how a forward clicky works.



A couple more photos added 1-29-08:



Closeup of the metal disc as it makes contact with switch contacts (spring under disc removed). The disc overlaps the contacts about 1 - 1.5 mm on each side.




Straight on closeup for a better angle.

[KeyGrip]

That's pretty cool. I too enjoy seeing the guts of mechanical devices.

[Crenshaw]

It might have been the plastic parts having problems..like the toothed edges..

or maybe the caseing of the switch has a ridge or something

Crenshaw

[srvctec]

It might have been the plastic parts having problems..like the toothed edges..

or maybe the caseing of the switch has a ridge or something

Crenshaw

That's what I'm guessing- the smaller plastic part was probably not turning properly inside the larger plastic part which would cause the protrusions to hang up on the casing instead of going down into the slots.

[Crenshaw]

Lol, but its still a good light yes? im deciding between posting a WTB that, and a jetbeam pro I...the foward clicky is VERY appealing

Crenshaw

[KeyGrip]

..the foward clicky is VERY appealing

Forward clickies rule.

[Lite_me]

If one was to take apart their switch like you did here, to lube or clean the contacts, can it be reassembled securely and reused? It doesn't look like you had to break anything. Did you merely have to unsolder it to get it apart?

I had my switch out once to deoxit the contact parts underneath, just to be sure, and remembered that my switch had a black button where yours has yellow. That probably doesn't mean much.

[shinbone]

Based on what I see of the parts shown there are three areas that could stick.

The first is the body tube where the plunger parts ride in, some external part out of tolerance, some flashing, or little to no lubricant.

Second is the metal disk where it makes contact with the two metal tabs (BTW, they look like the starter contacts in my truck). It's difficult to tell from the photos, but if that disk is slightly under sized it may be getting stuck under one of the metal tabs rather than simply touching the top of them.

The third is an area that seemed to be problematic with my surefire switches and that is the tooth interface between the two plastic button /plunger parts (look like ballpoint pen parts). On my Surefires the two indexing parts would stick at the top of the travel where they should ride over and then descend, instead they would just stick at the peak resulting in a constant on condition. After lubing the parts they worked normally.

[srvctec]

If one was to take apart their switch like you did here, to lube or clean the contacts, can it be reassembled securely and reused? It doesn't look like you had to break anything. Did you merely have to unsolder it to get it apart?

I had my switch out once to deoxit the contact parts underneath, just to be sure, and remembered that my switch had a black button where yours has yellow. That probably doesn't mean much.

Cool avatar, BTW!

The top does just come off with some careful prying with a knife. You wouldn't even have to unsolder it (in fact, I would discourage unsoldering it, as the more the contacts are unnecessarily heated up, the more the plastic they are mounted in will melt, causing more problems).

One of the pegs did break when I removed the top, but I'm not sure how since I was so careful taking it apart. My only concern with putting it back together, would be that I'm not sure how secure the top piece would hold onto the pegs after being removed.

[srvctec]

Based on what I see of the parts shown there are three areas that could stick.

The first is the body tube where the plunger parts ride in, some external part out of tolerance, some flashing, or little to no lubricant.

That's what I thought at first, so I lubed the top of the switch where the button protrudes with De-Oxit Gold and this actually made it worse. I realize De-Oxit Gold isn't actually a lubricant, but it has some lubricating qualities and I also thought it wouldn't hurt to get some of it into the switch to help with better contact between conducting surfaces. I wound up cleaning out the switch with contact cleaner to get the De-Oxit out, which made the switch workable, at least until I replaced it.

Second is the metal disk where it makes contact with the two metal tabs (BTW, they look like the starter contacts in my truck). It's difficult to tell from the photos, but if that disk is slightly under sized it may be getting stuck under one of the metal tabs rather than simply touching the top of them.

I just added a couple of photos to the first post, more clearly depicting how these parts mate. The disc actually overlaps the contact on each side by at least 1 - 1.5 mm.

The third is an area that seemed to be problematic with my surefire switches and that is the tooth interface between the two plastic button /plunger parts (look like ballpoint pen parts). On my Surefires the two indexing parts would stick at the top of the travel where they should ride over and then descend, instead they would just stick at the peak resulting in a constant on condition. After lubing the parts they worked normally.

This is actually what I think was happening, although lubing mine made it worse, which leads me to think that the spring isn't quite stiff enough.

I think that another thing may have come into play here as well is how these switches are soldered onto the circuit board. EdgeTac actually sent me more than one switch to replace my faulty switch with. I picked the best feeling switch of the lot- the one that felt like it had the most click and smoothest operation. I then folded the leads under the body of the switch just like they did at the factory prior to soldering it onto the board. I clamped the switch down and proceeded to solder it into place. When I was done, the switch wouldn't hardly click on. My only guess here (I should take it apart to verify this) is that the contacts are now probably ever-so-slightly angled up inside the switch (because of the heat of soldering), preventing the disc from traveling down far enough to allow the button (ball point pen mechanism) to lock properly. I have to really push it down hard to get it to lock on. So on the second switch, I cut the legs off and soldered it into place and it works fantastic.

If there are any other pics anyone would like me to take of these parts, let me know, as I still have them on my workbench.

[Lite_me]

Cool avatar, BTW!

Tanks! I'm not surprised you like it, cause I like yours. When I first joined and didn't have one yet, I ran across the one you are using and was going to use it, but before I had a chance to upload it I ran into one of your posts. Darn I said, someone's using it already. Anyway, they both look reeally good with the Heavy Metal theme.

The top does just come off with some careful prying with a knife. You wouldn't even have to unsolder it (in fact, I would discourage unsoldering it, as the more the contacts are unnecessarily heated up, the more the plastic they are mounted in will melt, causing more problems).

One of the pegs did break when I removed the top, but I'm not sure how since I was so careful taking it apart. My only concern with putting it back together, would be that I'm not sure how secure the top piece would hold onto the pegs after being removed.

Thank you for this information. It is very helpful.

That's what I thought at first, so I lubed the top of the switch where the button protrudes with De-Oxit Gold and this actually made it worse. I realize De-Oxit Gold isn't actually a lubricant, but it has some lubricating qualities and I also thought it wouldn't hurt to get some of it into the switch to help with better contact between conducting surfaces. I wound up cleaning out the switch with contact cleaner to get the De-Oxit out, which made the switch workable, at least until I replaced it.

This is exactly what I was afraid of. I was thinking of 'lubing' the switch through the switch button using Deoxit and also hopefully have some of it migrate to the contacts. I posted somewhere my fears of it screwing something else up. You've answered that also.

Thanks for the great pictures and info on the soldering too. All of this was much appreciated.

[srvctec]

Thanks for the great pictures and info on the soldering too. All of this was much appreciated.

Glad it's of some use to someone else. I sometimes wonder if I'm alone in my quest to find out how everything works and is made.

[Marlite]

Glad it's of some use to someone else. I sometimes wonder if I'm alone in my quest to find out how everything works and is made.

srvctec: Area 51 is tuned in to your wavelength since your last visit.

You posted a sweet one a year or so ago when you researched and posted the WriteRight screen protectors disclosing the Circuit City clearance at a super discount for $3.19 a pack of 12. Wow! Your pic were terrific. I used some and gave some away they were great for diffusing rings and artifacts!

The Nitecore Pre sale was reminiscent of the JetBeam there was a lot of ranting against emilion and he tried to please everyone. Many could care less that it cost him loads for all the problems trying to be Flashaholic #1.

Regards the tail clickie a pal emailed his was failing and considered selling it. Many reports of ongoing failures he said and I remembered the srvctec post to YL Wong and said mine works just fine and emailed him back, stating many rant because they had a bad day, or the wife said "you paying with lights again" or, you broke your PC board modding then burned your self on the soldering iron. I idly clicked mine while watching the TV five times no problem. 5 more clicks and and a failure on the third one, what! some more clicks and now intermittent and the clicks were heard but no light! +&%$#(ll. It died! I opened the switch and examined it since momentary still worked it has to be a mechanical failure. Fragile feel like air escaped. (Like I know electrical or for that matter mechanical) hey I'm just a user! I saw a ball point pen type switch, oh boy I know pens I've taken many apart and tell my wife I need another one to make one good one out of 2, never found 2 the same and have a box full. I got my can of silicone spray and squirted some into a small pill bottle brought out a hypodermic syringe drew just enough to fill the needle only and put 1 drop on each side of the plastic switch and worked it 12 times and replaced it in the tail. Poured alcohol in the top squirted and cleaned the needle for the next fix.
Presto It worked! YMMV but 3 hours later it still works.
No other problems except the crenelations, my tolerance is not improving it's so sharp I cut myself. This is my rant!

I did the tailstand O ring mod, and was forced to use a hotel shampoo bottle for a bezel cover for protection, (may grind the crenelations off) and the cap for solid tailstand. The bottle part opaque or white is 2-1/2" long so is also my diffuser.

Hope this works for you guys and girls too!
marlite

[Khaytsus]

Wait, so EdgeTac sent you a replacement SWITCH but not the switch/spring whole assembly that just goes into the tailcap?? Surely I'm reading this wrong.

Mine has failed in the same manner, and it sounds very silly for them to make you solder stuff to fix a defective switch. Although I wonder, is it defective, or is it poorly engineered since this is at least 5-6 people now I'm reading have had theirs fail.

[srvctec]

Wait, so EdgeTac sent you a replacement SWITCH but not the switch/spring whole assembly that just goes into the tailcap?? Surely I'm reading this wrong.

Ms Wong said she could send me the entire assy already soldered (spring, pc board and switch as a unit), but if I could solder, then she could send me a switch, since the assemblies were not ready yet and I would have to wait a couple of weeks. Well, I'm an electronics technician for almost 20 years and soldering is right up my ally, so I requested the switch by itself.

Mine has failed in the same manner, and it sounds very silly for them to make you solder stuff to fix a defective switch. Although I wonder, is it defective, or is it poorly engineered since this is at least 5-6 people now I'm reading have had theirs fail.

I think the problem may just be in how the switches are soldered onto the pcb (see my post #10, last paragraph). With the legs of the switch folded under for soldering, there is a tendency of the entire leg (including the contact part of it on the inside of the switch) to move when soldered because of the heat produced. Since the leg is just in plastic, once it is heated for soldering, the plastic will be melted slightly causing/allowing the leg to move which in turn causes the contact surface of the button of the switch to not mate at the correct height. If this happens, the switch mechanism (ball point pen part) can't operate properly if the travel of it isn't sufficient. Part of the reason this happens is because if the legs are just folded under the body of the switch, it is impossible to get a perfect 90 degree angle of it around the edge because of it springing back a little. When the switch is then clamped down to the pcb prior to being soldered, the metal leg will bend to 90 degrees under the clamping force. But once heated, something has to give somewhere, which is inside the switch since the folded under part has nowhere else to go.

Hope this makes sense! It's probably clear as mud now!

[srvctec]

My only concern with putting it back together, would be that I'm not sure how secure the top piece would hold onto the pegs after being removed.

Nothing like quoting myself.

But I just realized something. The switch only has to hold together long enough and good enough to survive being put back into the tailcap. Once it's screwed down inside the tailcap, it can't move at all anyways because of the washer that presses down against the top half of the switch.

[Khaytsus]

Ms Wong said she could send me the entire assy already soldered (spring, pc board and switch as a unit), but if I could solder, then she could send me a switch, since the assemblies were not ready yet and I would have to wait a couple of weeks. Well, I'm an electronics technician for almost 20 years and soldering is right up my ally, so I requested the switch by itself.

Understand not wanting to wait.. BTW, how did you contact EdgeTac? I've tried a PM on CPFM but haven't heard back yet.

I think the problem may just be in how the switches are soldered onto the pcb (see my post #10, last paragraph). With the legs of the switch folded under for soldering, there is a tendency of the entire leg (including the contact part of it on the inside of the switch) to move when soldered because of the heat produced. Since the leg is just in plastic, once it is heated for soldering, the plastic will be melted slightly causing/allowing the leg to move which in turn causes the contact surface of the button of the switch to not mate at the correct height. If this happens, the switch mechanism (ball point pen part) can't operate properly if the travel of it isn't sufficient. Part of the reason this happens is because if the legs are just folded under the body of the switch, it is impossible to get a perfect 90 degree angle of it around the edge because of it springing back a little. When the switch is then clamped down to the pcb prior to being soldered, the metal leg will bend to 90 degrees under the clamping force. But once heated, something has to give somewhere, which is inside the switch since the folded under part has nowhere else to go.

Hope this makes sense! It's probably clear as mud now!

Nah, I understand what you mean. However, my guess is that the parts gum up after a while, perhaps dust, plastic wear, etc.. Just like cheap pens tend to do the same thing. Cleaning the parts temporarily fixes it, but the design itself is IMO inherently flawed.

Using this thread I went ahead and carefully opened up the switch with exacto knife and jewelers screwdrivers and cleaned the plastic bits and put silicone spray on 'em and so far I've clicked about 25 cycles and no failures. I suppose if it happens again, I'll open it back up, it's easy enough to do.

[srvctec]

Understand not wanting to wait.. BTW, how did you contact EdgeTac? I've tried a PM on CPFM but haven't heard back yet.

I contacted Ms. Wong (EDGETAC) via pm (she hasn't even logged in since the 5th of this month). You won't be able to get a response from them until after the Chinese New Year which started Feb 7th and goes through the 15th this year. The whole country shuts down during this celebration.

Glad you got your switch working again!

[Khaytsus]

I contacted Ms. Wong (EDGETAC) via pm (she hasn't even logged in since the 5th of this month). You won't be able to get a response from them until after the Chinese New Year which started Feb 7th and goes through the 15th this year. The whole country shuts down during this celebration.

Glad you got your switch working again!

Righto, rats and all ;-) I'm fairly patient, I knew they were still on holiday or just coming off holiday.

Thanks, and yeah, so far still going!

[e2x2e]

The mechanism(the plastic part) kinda looks like a Parker pen mechanism.