So ive been using RDA's for a few months now on vw devices. Decided to get my first mech mod, and did all the research, and mech/battery saftey. I do have a good understading of OHMs law, and how electricity works. Now ive tried this mod with 2 seperate RDAs, with two different builds and im getting the same result. Now this is the first clone i ever bought, and it was the Stingray with black stainless steel. Now ive clean the mod several times with toothpaste and a tooth brush, but the mod is heating up right at the joint. These mods screw together, so that u can use multiple batterys. Whenever im firing, the joint is heating up faster than the coil. For me, that sounds like the joint has some resistance, and thus heating up due to electricity having to do work to move thru it. The only thing i dont get is that ive clean it, and its still happening. I dont know what to do at this point, and im clearly missing somehting. The first built i had on it was 1ohm, on my goon. the second was a .28 with my origen v2, and i did try one more time just now, with my goon again at .3. The coil ohms isnt making a difference, and its still heating up just at that joint to the point u cant hold it. I popped the battery out after the first time, cause i was scared i might have shorted something, but the battery was nice and cool like it should be. Any help would be much appriciated, Thanks.
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Try some noalox or deoxit gold on those threads. Also are you sure you got all the toothpaste off? If you didn't that would cause a bad connection as well.
If your mod is clean it should not heat up faster then coils. Noalox and deoxit may make it less prominent but grease will not fix the problem. It is a badly constructed tube. Hot connections and switch are most common problems with cloned tubes.
Yea all the tooth paste is off. I've scrubbed it clean. I've taken it apart a few times trying to figure out what's going on, and I was starting to think it was the mod itself; but wanted to make sure.
It really shouldn't heat up at all with a 1 ohm coil!
If the tube is anodized or coated with anything, that is probably your trouble. You say it is blackened stainless. Use a dremel and polish to the stainless both internal and external threads, so that the point of contact is bright and clean.
Common problem with coatings.
If the tube is anodized or coated with anything, that is probably your trouble. You say it is blackened stainless. Use a dremel and polish to the stainless both internal and external threads, so that the point of contact is bright and clean.
Common problem with coatings.
So I checked all my contact points to make sure they are good, and I think the negative contact to the battery is on some of the pvc battery coating. I'm using 25r's and they wrap the negative side pretty far over the corners, and the negative contact on the mech is pretty big. I have new wraps coming, because I had a couple battery's I needed to wrap, and no I haven't used these battery's in the mod. I'm gonna rewrap these and see if that was the issue. If not than I'll take the Dremel to it.
Only tubes that I use are Kennedy roundhouse and SMPL. Both of those can take the battery either side up or down. Mech mod doesn't recognize positive or negative.all it does is connect and conduct. As long as your positive isn't dented or wrap isn't damaged you should be able to do it as well.
So I think I fixed it. The top pin on the stingrays are "auto" adjustable, and I don't think the pin was making great contact. They have a chrome cover cap, and I shaved that down a bit. I'm actually gonna grind it down a bit more, but the pin is making way better contact. I threw the goon on it, and fired it a couple times and had no problems. Since I was having issues though I'm kinda hesitant to use it, but as long as it's working I'll get more comfortable with it and use it more. Thanks for all the help.
So I definitely found the culprit. Scalewiz, you were right. I thought the "blackened" steel was a treatment pre molding, because it doesn't make sense to coat something that screws together and needs to conduct electricity. But I took it to a wire brush wheel, and the coating came right off.
True, but I don't know how I'd feel about having my enclosure being live... ...internally, it should be fine with well-wrapped battery. It creates a risky situation, though. A tear would lead to a nasty hard short across the negative battery body and the positive mod the moment you push the button. Besides, what if you pocket-fire a mod with an energized body and you just happen to have something metal in your pocket, too? Or maybe you're holding it and firing it intentionally while wearing a conductive ring?
It might actually be interesting to have a mod specifically designed to be run with the battery reversed. You know, insulated inside and out to prevent shorts on both ends. The body IS the better conductor. Couple this with an atty that completely isolates the barrel from the mod and atty base and you may have something pretty cool going on.
Lol. I wish. Kennedy has something cool going on since they designed Roundhouse to take battery upside down. That's why it has press. release holes on the bottom by the switch. SOI made a Subzero same way as well. I do wear a silver ring and ring won't fire it no matter how I bridge it bridge between tube and switch.
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A mech does recognize positive and negative. If you flip a battery in a mech, the positive runs up the tube to the negative posts of the atomizer, across the coil and back down the positive post to the negative side of the battery. No big deal if your wraps are good. However, if you get some exposure on the side of the battery and it contacts the tube that is a dead short as the positive current running up the tube hits the negative side of the battery. If you're gonna run it that way, be very careful with your batteries.
Read my post. It is clearly said "as long as positive isn't dented, and wrap isn't damaged"...mech tube doesn't recognize shit since there is no boards or chips to recognize it. Current runs the other way around and everything still works same. That's why it is a mechanical fucking tube.
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Strip the wrap off a battery and see if it doesn't recognize that the current is running the wrong way, how about that?
Unless you are a compete idiot you are not going to put naked battery into that tube. If you are an idiot and decide to do so, result will be the same no matter is the + up or down. Learn your shit.
Learn my shit? I know my shit. I'm not randomly advising people to flip the batteries in their mechanical mods as a quick fix for a mod that's already shorting with proper battery insertion. Know what I'm saying?
No. Have no idea what are you "saying?" You don't know shit, and that's a fact. There is more then one tube designed to run + down. Kennedy Roundhouse, SOI subzero are designed to have a "hot" tube once fired since switch is closing a positive on battery, have both of em so I can talk about it. Your "unwrap the battery" theory doesn't make any sense, and a whole statement doesn't have a point. So,..you are full of shit and bent out of shape cause you have nothing to bring into this argument and prove your point.
This discussion wasn't about a Roundhouse or a Subzero. It was about a Stingray clone, which is not designed to run a battery positive side down. See? I do know what I'm talking about. Did you not notice that it was about a Stingray, or are you desperately trying to score vape cool points? I'm just saying he should probably run batteries in the proper direction to avoid potential issues.
This post is why I told him that he can try to put them up side down. You still have no clue what are you talking about, and haven't made any good point. You can't even back your own statements.
Wtf is your point here? You have a short no matter what. Grow up boy.
Do you even comprehend that coil will light up even when you switch polarity?
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You can say whatever you want about what I don't know. I don't need your approval. That's the difference between you and I. You get all bent because I pointed out that it's not wise to run a battery in reverse position in a mech mod. I don't care if you get bent. I would rather newbies who might read this thread realize that this is a bad idea.
Now, as to your assertion that "you have a short no matter what" you're wrong on that too. You only have a short if the negative touches the positive. I'm running an Infected box mod right now with Samsung batteries in it where the positive contact is smaller than the positive post. Therefore, if I ran it with unwrapped batteries it wouldn't short. However, it would be silly to do that. Even sillier than flipping batteries in a mod with a known fault to try to "fix" the fault. Why not just fix the issue with the mod?
Here's what you need to understand. I don't care about what you think you know. I care about a newbie who will see your post and think he can fix a mech with an issue by flipping the battery. That's the point here. If you were a little slow to get that, that's your problem not mine.
Now, as to your assertion that "you have a short no matter what" you're wrong on that too. You only have a short if the negative touches the positive. I'm running an Infected box mod right now with Samsung batteries in it where the positive contact is smaller than the positive post. Therefore, if I ran it with unwrapped batteries it wouldn't short. However, it would be silly to do that. Even sillier than flipping batteries in a mod with a known fault to try to "fix" the fault. Why not just fix the issue with the mod?
Here's what you need to understand. I don't care about what you think you know. I care about a newbie who will see your post and think he can fix a mech with an issue by flipping the battery. That's the point here. If you were a little slow to get that, that's your problem not mine.
Electrically here is the difference between the two unwrapped battery options.
1. +ve up and -ve touching tube : Bypasses the switch - Auto-fires.
2. -ve up and -ve touching tube : Bypasses coil - hard short battery when fire button pressed.
Neither would be much fun.
1. +ve up and -ve touching tube : Bypasses the switch - Auto-fires.
2. -ve up and -ve touching tube : Bypasses coil - hard short battery when fire button pressed.
Neither would be much fun.
By flipping the battery he could figure out is that wrap too long as he was suspecting, not fix the tube. Your whole "unwrap" the battery is an idiotic statement since I said that he can flip it if positive isn't dented and battery wrap is not damaged. There is no " unwrap" the battery option that will end up good, so I don't get it why would you even come up with that. It doesn't prove anything since we are discussing flipping a healthy battery. I am not bent out of shape baby doll, just arguing my point and can't find any sense in you comparison.
Telling someone to put few ml of gasoline directly in carbs if bike won't start isn't same as telling em to pour a gallon over the engine and press the start.
Telling someone to put few ml of gasoline directly in carbs if bike won't start isn't same as telling em to pour a gallon over the engine and press the start.
mechs dont give a shit if cells are + up or + down.
i personally put the + side xlosest to thr vent holes, some mechs have vent holes closer to the 510 side, others closer to the button side, some vent through the button itself...
it doesnt matter, close the circuit itll channel around either way.
with a tear in the wrap you are risking being fucked either way.
the flay tops are designed to vent through the + side so its a good idea to keep that pointed at the closest possible exit lol.
i wouldnt recommend using shitty clones that come with faulty design.
Sent from my SM-N920T using Tapatalk
i personally put the + side xlosest to thr vent holes, some mechs have vent holes closer to the 510 side, others closer to the button side, some vent through the button itself...
it doesnt matter, close the circuit itll channel around either way.
with a tear in the wrap you are risking being fucked either way.
the flay tops are designed to vent through the + side so its a good idea to keep that pointed at the closest possible exit lol.
i wouldnt recommend using shitty clones that come with faulty design.
Sent from my SM-N920T using Tapatalk
Of course it was an idiotic statement. It was in response to this idiotic statement by you.
Try to follow me here. If you insert a battery into a mech mod properly, it runs the circuit up the positive post, across the coil, back down the negative and through the tube to the switch and back into the battery through the button on the bottom. If you insert it in reverse, that flow of current gets reversed. Thus, with an unwrapped battery you would get a dead short if inserted in the reverse position. If you inserted it properly, you would get an autofire but no short. Since you were unable to figure this out using simple logic, I figured you could unwrap a battery and try both positions and the mod would teach you exactly what it does and does not recognize.
I know what happens either way, but thank you for your words of enlightenment . There was no "unwrapped" battery in this case until you brought it here. Somehow you got "unwrap it" into the troubleshooting the battery/tube issues as an example of I don't know what. Do yourself a favor and read this tread from the first post down so you can figure out your own stupidity, once you do it in a comprehensive way, your pussy will probably stop bleeding.
This is a warning about reverse battery polarity in metal tubemods, and a discussion of related issues.
WARNING
DO NOT insert APV batteries 'the wrong way round', with the negative pole inserted first and at the top of the tube
This is extremely poor practice, and should certainly never be seen as a design feature since it causes the device body to become the positive line. No electrical design ever makes a machine body the positive pole (and therefore 'live'), it is classed as a design error.
Why?
There is one practical reason and one theoretical reason. The theoretical one first: a machine casing is always negative or earth, because making it positive introduces the possibility of fault conditions that are unlikely or impossible with the casing negative, or 'earth' as it is often called (though incorrectly, if you are being fussy). This is well-illustrated by the practical reason this is never done in an APV, detailed below in 'Why reversing the battery is dangerous'.
Battery structure
A rechargeable battery is contained within a metal 'can' or container, and this can is negative. The entire outer surface of a battery is negative, and the positive terminal at the top is insulated. The battery can is covered by a wrapper or label, and this insulates the battery. It is not considered a vital measure to have a robust wrapper that cannot easily wear through, since any short [1] will be to 'earth', i.e. negative, and there are unlikely to be any serious consequences.
Even so, there are two possible consequences of wear and tear on an APV battery label:
1. If the battery can shorts to earth then the new negative path may bypass a fuse such as a hot spring. Then, if there is an over-current event such as a shorted-out adapter, the fuse will not protect against high current flow and a fire may result.
2. If the battery is a protected Li-ion cell then the protection will be bypassed, and it becomes an unprotected lithium cell.
It is better if an APV incorporates some form of fuse in the positive circuit so that a battery can short to earth does not bypass a negative-line fuse. Theoretical circuits always switch and fuse the positive line and this is why.
Why reversing the battery is dangerous
In a metal tubemod, the casing is negative, as this is standard practice for many DC devices - cars for example (although theoretically this is second-class design [2]). A car body is negative. It means that shorts will usually have no consequences as a negative to negative short is usually not significant, since the positive side is fused. If a pos to neg short occurs, then a fuse blows immediately.
In an APV, as we have seen, a neg to neg short introduces the possibility that fuses and protection circuits may be bypassed, and it therefore requires two faults to produce an incident - a neg to neg short through a worn label, plus a shorted-out atomizer adapter or similar.
However, if the battery is reversed, and the device's operational polarity is reversed from normal, this is a different matter. With the casing positive and 'live', a torn or worn battery label then allows a direct neg to pos short that could bypass any fuse wherever fitted, and a fire will result. The full battery discharge current will pass through the short-circuit and the battery will go into meltdown. There is an explanation of the circuit in the notes at [3].
This is a serious incident even with a safer-chemistry cell such as Li-Mn. In the case of a plain Li-ion cell or even a protected one (since the protection circuit is at the other end of the battery and has been bypassed), we are looking at a meltdown with flames, significant outgas and possibly an explosion, even with a single battery. With a top-quality Li-Mn cell a meltdown is assured, and possibly worse; if the cell is not of the most expensive type then there may be more risk. In fact reverse-polarizing a battery is probably the best way to create a situation where an explosive event might occur with a single battery.
NEVER reverse your battery
NEVER design a metal tube APV to work with reversed polarity and a positive machine casing
An exception to this might be for example if you have a robust internal insulator such as a thick mylar internal battery sheath that totally and absolutely prevents the battery can from shorting out, and cannot fail; but there are no good reasons to design a device with a live casing.
It's still extremely poor engineering practice to design a device with a positive case even if 'safety measures' are taken, and no engineer worthy of the name would do it. It's the kind of beginner's mistake that results, eventually, in them becoming experts - after a long period of time and many mistakes that cost money or injury. You can't blame beginners who weren't taught properly for making this kind of mistake; it's just that you don't want to be buying products created during their learning process...
Why do people want to insert batteries the wrong way round?
Perhaps because a battery that fails will vent first from the positive end - you can see the tiny gas vents around the positive terminal at the top. All rechargeables have these. Maybe the device being used only has gas vents at the bottom, so that the user assumes that it will be safer if the battery pos terminal is by the tubemod's gas vent.
There are so many faults in this reasoning that it is futile listing them and would take too much space. Just don't do it.
------------------------
Notes
[1] A 'short' in electrical slang is a short-circuit / dead short - a shortened electrical path not designed for and that has no resistance in the circuit, leading to full current being drawn, and which may have unwanted consequences such as a fire, damaged components, or a blown fuse - or maybe just some sparking, if you're lucky. It's why an electrician is known as a 'sparks' in the construction trade. With lithium cells, contained in a product that is used in front of the face, the consequences can be serious and all possible measures need to be taken to avoid a fault chain leading to an explosive event. If a supplier sells a device that is predisposed to fail violently when only one fault occurs, this might be construed as negligence. It is hard to see a reverse-polarised design as anything other than negligent.
[2] The theoretical 'perfect' electrical circuit is an insulated 2-wire circuit. For practical or economic reasons, a machine body can be made one side of the circuit, and this side is always negative. One example is a car. The negative side is sometimes called 'earth' although strictly speaking that is incorrect as there is no real ground. In the early days of electrical design, the machine case was occasionally made positive, but that has long been avoided due to the problems it causes. You can only get away with this, if lucky, in low-voltage circuits - imagine if this was done with a mains electrical device - a good illustration of why this should not be done. The consequences of having your fridge 'live' are not pleasant; equally, there is no reason to make a low-voltage device casing live either. It introduces numerous issues even though the voltage itself is not sufficient to kill.
[3] Explanation of circuit: dead short with machine casing live
1. A metal tubemod with or without a hot spring fuse has a battery such as an IMR Li-Mn 18650 lithium cell inserted the wrong way round.
2. There are no electronic protections in the APV. However, this is irrelevant; just like the protection circuit on a protected Li-ion cell inserted the wrong way round, any electronic protections will be bypassed in any case, since they are at the (original) positive end of the circuit, which has been bypassed by reverse polarizing the battery. A neg to pos dead short through the battery cannister will bypass the protections.
3. After frequent charge cycles the battery label starts to wear through. Perhaps there is a sharp edge that scrapes the label; perhaps there is a high point somewhere in the tube internally; perhaps after hundreds of charges there is too much wear for the label material. It doesn't really matter why, as we know that battery labels do wear through (or get torn).
4. The battery can is negative and it shorts out on the body of the tubemod, which is 'live' or positive as the battery was inserted in reverse.
5. The device is in use, or standing unused - it doesn't matter which, since no switch operation is needed to complete this circuit: batt pos to hot spring >> hot spring to device body >> device body to battery can >> battery internal circuit to batt pos.
6. The IMR cell delivers 30 amps DC current instantly through the short-circuit, which has very low resistance.
7. The hot spring (if present) does nothing since when it collapses, the battery just follows it down, and the positive pole sits directly on the tube body.
8. 30 amps continues to pass though the circuit, a fire starts at the battery can to tube body contact point and the two metal surfaces may even weld together.
9. The battery goes into meltdown.
Even a typical penlight AA cell can deliver 10 amps in a dead short. All lithium rechargeables deliver much higher currents than this, and some large models can deliver 70 amps instantly (26650 Li-FePo4). You could weld using a 2.5mm welding rod with a current as high as this.
WARNING
DO NOT insert APV batteries 'the wrong way round', with the negative pole inserted first and at the top of the tube
This is extremely poor practice, and should certainly never be seen as a design feature since it causes the device body to become the positive line. No electrical design ever makes a machine body the positive pole (and therefore 'live'), it is classed as a design error.
Why?
There is one practical reason and one theoretical reason. The theoretical one first: a machine casing is always negative or earth, because making it positive introduces the possibility of fault conditions that are unlikely or impossible with the casing negative, or 'earth' as it is often called (though incorrectly, if you are being fussy). This is well-illustrated by the practical reason this is never done in an APV, detailed below in 'Why reversing the battery is dangerous'.
Battery structure
A rechargeable battery is contained within a metal 'can' or container, and this can is negative. The entire outer surface of a battery is negative, and the positive terminal at the top is insulated. The battery can is covered by a wrapper or label, and this insulates the battery. It is not considered a vital measure to have a robust wrapper that cannot easily wear through, since any short [1] will be to 'earth', i.e. negative, and there are unlikely to be any serious consequences.
Even so, there are two possible consequences of wear and tear on an APV battery label:
1. If the battery can shorts to earth then the new negative path may bypass a fuse such as a hot spring. Then, if there is an over-current event such as a shorted-out adapter, the fuse will not protect against high current flow and a fire may result.
2. If the battery is a protected Li-ion cell then the protection will be bypassed, and it becomes an unprotected lithium cell.
It is better if an APV incorporates some form of fuse in the positive circuit so that a battery can short to earth does not bypass a negative-line fuse. Theoretical circuits always switch and fuse the positive line and this is why.
Why reversing the battery is dangerous
In a metal tubemod, the casing is negative, as this is standard practice for many DC devices - cars for example (although theoretically this is second-class design [2]). A car body is negative. It means that shorts will usually have no consequences as a negative to negative short is usually not significant, since the positive side is fused. If a pos to neg short occurs, then a fuse blows immediately.
In an APV, as we have seen, a neg to neg short introduces the possibility that fuses and protection circuits may be bypassed, and it therefore requires two faults to produce an incident - a neg to neg short through a worn label, plus a shorted-out atomizer adapter or similar.
However, if the battery is reversed, and the device's operational polarity is reversed from normal, this is a different matter. With the casing positive and 'live', a torn or worn battery label then allows a direct neg to pos short that could bypass any fuse wherever fitted, and a fire will result. The full battery discharge current will pass through the short-circuit and the battery will go into meltdown. There is an explanation of the circuit in the notes at [3].
This is a serious incident even with a safer-chemistry cell such as Li-Mn. In the case of a plain Li-ion cell or even a protected one (since the protection circuit is at the other end of the battery and has been bypassed), we are looking at a meltdown with flames, significant outgas and possibly an explosion, even with a single battery. With a top-quality Li-Mn cell a meltdown is assured, and possibly worse; if the cell is not of the most expensive type then there may be more risk. In fact reverse-polarizing a battery is probably the best way to create a situation where an explosive event might occur with a single battery.
NEVER reverse your battery
NEVER design a metal tube APV to work with reversed polarity and a positive machine casing
An exception to this might be for example if you have a robust internal insulator such as a thick mylar internal battery sheath that totally and absolutely prevents the battery can from shorting out, and cannot fail; but there are no good reasons to design a device with a live casing.
It's still extremely poor engineering practice to design a device with a positive case even if 'safety measures' are taken, and no engineer worthy of the name would do it. It's the kind of beginner's mistake that results, eventually, in them becoming experts - after a long period of time and many mistakes that cost money or injury. You can't blame beginners who weren't taught properly for making this kind of mistake; it's just that you don't want to be buying products created during their learning process...
Why do people want to insert batteries the wrong way round?
Perhaps because a battery that fails will vent first from the positive end - you can see the tiny gas vents around the positive terminal at the top. All rechargeables have these. Maybe the device being used only has gas vents at the bottom, so that the user assumes that it will be safer if the battery pos terminal is by the tubemod's gas vent.
There are so many faults in this reasoning that it is futile listing them and would take too much space. Just don't do it.
------------------------
Notes
[1] A 'short' in electrical slang is a short-circuit / dead short - a shortened electrical path not designed for and that has no resistance in the circuit, leading to full current being drawn, and which may have unwanted consequences such as a fire, damaged components, or a blown fuse - or maybe just some sparking, if you're lucky. It's why an electrician is known as a 'sparks' in the construction trade. With lithium cells, contained in a product that is used in front of the face, the consequences can be serious and all possible measures need to be taken to avoid a fault chain leading to an explosive event. If a supplier sells a device that is predisposed to fail violently when only one fault occurs, this might be construed as negligence. It is hard to see a reverse-polarised design as anything other than negligent.
[2] The theoretical 'perfect' electrical circuit is an insulated 2-wire circuit. For practical or economic reasons, a machine body can be made one side of the circuit, and this side is always negative. One example is a car. The negative side is sometimes called 'earth' although strictly speaking that is incorrect as there is no real ground. In the early days of electrical design, the machine case was occasionally made positive, but that has long been avoided due to the problems it causes. You can only get away with this, if lucky, in low-voltage circuits - imagine if this was done with a mains electrical device - a good illustration of why this should not be done. The consequences of having your fridge 'live' are not pleasant; equally, there is no reason to make a low-voltage device casing live either. It introduces numerous issues even though the voltage itself is not sufficient to kill.
[3] Explanation of circuit: dead short with machine casing live
1. A metal tubemod with or without a hot spring fuse has a battery such as an IMR Li-Mn 18650 lithium cell inserted the wrong way round.
2. There are no electronic protections in the APV. However, this is irrelevant; just like the protection circuit on a protected Li-ion cell inserted the wrong way round, any electronic protections will be bypassed in any case, since they are at the (original) positive end of the circuit, which has been bypassed by reverse polarizing the battery. A neg to pos dead short through the battery cannister will bypass the protections.
3. After frequent charge cycles the battery label starts to wear through. Perhaps there is a sharp edge that scrapes the label; perhaps there is a high point somewhere in the tube internally; perhaps after hundreds of charges there is too much wear for the label material. It doesn't really matter why, as we know that battery labels do wear through (or get torn).
4. The battery can is negative and it shorts out on the body of the tubemod, which is 'live' or positive as the battery was inserted in reverse.
5. The device is in use, or standing unused - it doesn't matter which, since no switch operation is needed to complete this circuit: batt pos to hot spring >> hot spring to device body >> device body to battery can >> battery internal circuit to batt pos.
6. The IMR cell delivers 30 amps DC current instantly through the short-circuit, which has very low resistance.
7. The hot spring (if present) does nothing since when it collapses, the battery just follows it down, and the positive pole sits directly on the tube body.
8. 30 amps continues to pass though the circuit, a fire starts at the battery can to tube body contact point and the two metal surfaces may even weld together.
9. The battery goes into meltdown.
Even a typical penlight AA cell can deliver 10 amps in a dead short. All lithium rechargeables deliver much higher currents than this, and some large models can deliver 70 amps instantly (26650 Li-FePo4). You could weld using a 2.5mm welding rod with a current as high as this.
When you get excessive heat from a section of the tube (more usually the switch or the 510) it will almost always mean you have a high resistance connection. In the case of an older mod that you have used a while it means you are overdue cleaning it. If it's a new mod then it may have some lacquer or other coating in the connection that needs to be removed. But now you know that - so you are learning your mech mod shit 
It's more likely with a clone but you should always test it for stuff like that and clean up/finish off what the factory did not, mistakes happen and QC can have an off day. You are gonna be plugging it into your face so a few minutes making sure it's up to standard is more of a necessity than an option.
It's more likely with a clone but you should always test it for stuff like that and clean up/finish off what the factory did not, mistakes happen and QC can have an off day. You are gonna be plugging it into your face so a few minutes making sure it's up to standard is more of a necessity than an option.
Or perhaps the design isn't faulty. Maybe it was designed to be used with the positive end up and some dope saw the "+" on the switch and, without understanding how a mechanical mod works, assumed that the manufacturer intended for them to run it with the positive side down when in fact they never did.
That kinda makes sense, I don't see anything in the design of either mod that would suggest it is meant to be used with the +ve down. I can see how someone with no electrical knowledge might think the cross cut in the switch was a battery direction indicator.