In the event of a short with a mech mod,

[Mrez]

What does one do? I mean other then briefly piss themselves? After my cloupor died on me I ended up purchasing my first mech mod. I am building my coils safely, testing everything, checking my numbers and amp draw, using good batteries (Sony Xtc4). I'm not over drawing my batteries, and I am not building crazy low ohm builds ( right now I've got a .6 and .8 build). So I am trying to be as safe as I can, but the unexpected could happen (the atty gets a bump, something get nudged the wrong way when putting on the atty cap etc). So if the short does happen, what will happen during the short, how quickly will it happen given my set up, and what do I do about it?

 

[The Torch]

Search Youtube for venting battery. A lot of the results include venting batteries in mechanical mods. The battery and your whole mod will get really hot before anything really violent happens (as long as you mod has at least one vent hole, else it will blow because of pressure build-up). If your mod gets really hot, let go of the fire button, put it down on a safe surface or throw it out the window and walk out for a few minutes.

To calculate the safety of your setup, you need basic knowledge of ohm's law:

Know what is the max steady amp output of your battery. I believe you mean the Sony VTC4. That one is 30 amps max. when the battery is in contact with a "charge", or coil, the output voltage is 3.7 volts. Divide 3.7 volts by your minimum 0.6 ohm coil and you get 6 amps, way lower than the battery's max output. If you want to be paranoid about it, let's say the battery still outputs the 4.2 volts you read when it is not in use: 4.2/0.6 = 7 amps, still way lower than the battery's 30 amp max.

THE OTHER POINT NO ONE EVER TALKS ABOUT: It is very important to know when your battery has reached it's minimum charge since this is a lithium-ion battery. As you vape, the battery's voltage will go lower. When the battery is measuring under 3 volts it is in real need to be recharged. Depending on the batteries, the lowest you can reach is 2.8 volts on a lithium-ion battery that is not connected to other than a volt meter. If your battery discharges lower than that, it will definitely not perform as well and will not last very long. Make sure you have a decent enough charger too.

I hope I am not overloading you with information or scaring you... change your batteries frequently enough and it will be safe to bring your mod to your lips. Batteries that vent are just brought to their limits and with a VTC4 on more than 0.5 ohms, the numbers are definitely on the safe side.

 

[Rossum]

Duck and cover?

Seriously, somebody brought this video to my attention in another thread; it should give you some idea of what you might expect.

 

[The Torch]

Duck and cover?

Seriously, somebody brought this video to my attention in another thread; it should give you some idea of what you might expect.

Duck and Cover: "...cover the back of your neck with your face..."
"Hello, my name is Troy Mclure, you might know me from such films as 'x-rays are okay' or 'gamma rays are not bad... once you get to know them'. We have just witnessed an A-bomb axplosion, but Timmy was smart enough to remember what he was taught in school: duck and cover. Good boy, Timmy! Now get back on that bicycle and go tell your parents an A-bomb just blew up near the park. It's no time to be sick on the way, Timmy... Your parents and your sister are counting on you!"

Rossum: (it was that or "birdy numnum...")

 

[Mrez]

Search Youtube for venting battery. A lot of the results include venting batteries in mechanical mods. The battery and your whole mod will get really hot before anything really violent happens (as long as you mod has at least one vent hole, else it will blow because of pressure build-up). If your mod gets really hot, let go of the fire button, put it down on a safe surface or throw it out the window and walk out for a few minutes.

To calculate the safety of your setup, you need basic knowledge of ohm's law:

Know what is the max steady amp output of your battery. I believe you mean the Sony VTC4. That one is 30 amps max. when the battery is in contact with a "charge", or coil, the output voltage is 3.7 volts. Divide 3.7 volts by your minimum 0.6 ohm coil and you get 6 amps, way lower than the battery's max output. If you want to be paranoid about it, let's say the battery still outputs the 4.2 volts you read when it is not in use: 4.2/0.6 = 7 amps, still way lower than the battery's 30 amp max.

THE OTHER POINT NO ONE EVER TALKS ABOUT: It is very important to know when your battery has reached it's minimum charge since this is a lithium-ion battery. As you vape, the battery's voltage will go lower. When the battery is measuring under 3 volts it is in real need to be recharged. Depending on the batteries, the lowest you can reach is 2.8 volts on a lithium-ion battery that is not connected to other than a volt meter. If your battery discharges lower than that, it will definitely not perform as well and will not last very long. Make sure you have a decent enough charger too.

I hope I am not overloading you with information or scaring you... change your batteries frequently enough and it will be safe to bring your mod to your lips. Batteries that vent are just brought to their limits and with a VTC4 on more than 0.5 ohms, the numbers are definitely on the safe side.

Thank you Torch, alot of that is information I've gone over and over again in prep to get a mech mod (something I was going to do in a few months while using my Cloupor, sadly, things didnt work out that way). I had already been checking my amp draw using steam engine and plugging in a different resistances to get a feel for where I wanted to be, .6-.9 ohm seemed to be the comfort zone for my battery with plenty of safe room to maneuver. I am less concerned about building low ohms and over heating the battery then I am about a freak short from whatever. If it shorts I am assuming I've got <.1 ohm equivlant and that will cause the heating to mod itself. Do I have time? Or is it rather instantaneous. Honestly the biggest fear is an accidental short while driving or in work. In my perfect world, I have a reliable high wattage box for out and about, and a few nice mechs for home use, or when I want to enjoy the style out and about.

I did also just buy a multimeter so I can keep an eye on the charge on my batteries. I did accidently over draw one of them to the point where it wouldn't fire yesterday, but a few hours on my xtar charger brought it right back up and was reading 4.1 off a fresh charge.

 

[Michael7]

Great question, I wad wondering the same thing the other day, what would I do if a short occurred when I was driving down the freeway or just couldn't pull over..... Throwing it out the window would probably be counted as a terrorist activity lol . But seriously I was debating what I would do.

I did accidentally short my vtc5 for about half a second when I had takin my atty off, and was messing around with my multi meter, I forgot to lock the fire button and while messing with the probes I managed the push hard enough to fire it and there was a spark. But the batt never got hot, I still immediately put it in a cup and in the sink just incase something happened.

Sent from my HTCEVOV4G using Tapatalk

 

[Mrez]

Duck and cover?

Seriously, somebody brought this video to my attention in another thread; it should give you some idea of what you might expect.

So I guess my question after watching that venting video, do most batteries behave in a similar way? It looks like if that were a real world situation, releasing the fire button would cut off the current into the shorted section. So if I did have a short, the mech body would get hot fairly quickly, I'd probably drop it and release the fire mechanism and wait for cool down to see what actually happened. My vaping habit is to do five or six pulls in a row then set it down for a little bit, unless I'm chaining in the car. It seems like I'd know right away that there was a problem, without the loss of my hand (or face). Short happens, mech body overheats quick, drop it, let it cool and take off the atty and inspect battery/atty/switch. Does that seem to be a fairly accurate assessment?

 

[The Torch]

If your mod gets questionably hot in your hand, time to let go of the button. If the heat keeps rising rather than stay put or lower, then you got a short on your firing button, which I have not heard of so far but is possible on a mech. If you run your ohms lower than what the battery can handle, then the heat might not have the time to warn you of an impeding nasty surprise. Not likely on a decent battery with enough lifespan left in it.

Please do change your battery for a brand new one when you think it's not lasting as long as it used to on a fresh charge and you should be fine. Shorter battery charge time is a sign it's aging or it has been discharged more than it likes. Lithium-ion batteries prefer frequent refreshing charges than to be discharged completely before a complete charge (beware of the urban myth... NiCad batteries need to be completely discharged to stay healthy, but those are still mainly living in cordless drills, but more and more cordless drills run on Li-Ions..)

About venting: once the battery starts venting, it is too late to save it's life; get rid of it aftrwards. It should stop venting shortly after the firing button is released. I'm against bottom firing buttons because standing a bottom firing button mod can easily keep firing if you stand them up. Just make sure there is no more contact and walk away from a venting battery as, even though very infrequent, toxic cloud release is still possible . Never run a mech that has no vent hole, else it can blow like a pipe bomb because of pressure buildup. You don't need such excessive holes you can read the battery from the side holes... just a small hole anywhere on the battery tube is plenty to prevent pressure buildup.

 

[HauntedMyst]

Find someone you think is a true idiot, then hit the fire button and use some crazy glue on it and slip it in their front pocket and run. It probably won't kill them but it may render them ineligible to breed there by helping further the species.

 

[nynvolt]

If you short, it will get hot fast. Unscrew the cap so the battery is no longer making a connection. It's happened to me when I screwed a protank 3 down too tight and a couple times with my Russian, positive post rotated. Was no big deal. Battery was warm but hadn't gotten Hot. Just have to be aware of what you're doing.

 

[The Build]

When they say hot they mean hot! My nemesis clone shorted and instantly blistered my finger-my sentinel m16 which is an original shorted when I stupidly forgot to tighten the base and it got me too-the worst was when the bottom pin popped out of my manhattan and connected with the battery in my pocket and ran until I suddenly felt burning...
All of this being said I have been at this for a long time and two out of three of these incidents were my fault-the battery never vented and other than frantically unscrewing the base of the manhattan to drop out the battery I have been fortunate
The most important thing is that you realize that your mod creates one giant circuit and that includes the body of the mod so make sure everything is tight (not too tight on the battery) and give it a couple of taps on the switch to look for heat-the mod should heat from the atty down-if you start to feel heat anywhere else first it is a bad sign of a short somewhere

 

[Mrez]

So maybe an unrelated question, do you keep the mod tight on the battery when not firing? Or a little loose so it has room to move up and down so as not to create a complete circuit.? Esp when you have it in a pocket or something?

 

[DaveP]

IMR High Drain batteries and a fuse should be standard equipment in a mech.

Vapesafe Fuse

 

[Mrez]

So maybe an unrelated question, do you keep the mod tight on the battery when not firing? Or a little loose so it has room to move up and down so as not to create a complete circuit.? Esp when you have it in a pocket or something?

 

[tj99959]

In the event of a short with a mech mod

Sometimes this!

 

[Mrez]

IMR High Drain batteries and a fuse should be standard equipment in a mech.

Vapesafe Fuse

I believe the Sony's are high drain. That fuse interests me. Its listed as a 7 amp saftey, so does that me it kicks on if I hit 7 amps? That might be perfect for me as that's around a .7 .8 coil if my understanding is correct.

 

[KenD]

So maybe an unrelated question, do you keep the mod tight on the battery when not firing? Or a little loose so it has room to move up and down so as not to create a complete circuit.? Esp when you have it in a pocket or something?

Tight, but not too tight. The battery should not move around in the tube but it should not be such subjected to too much pressure either

 

[Circa Survivor]

Duck and Cover: "...cover the back of your neck with your face..."
"Hello, my name is Troy Mclure, you might know me from such films as 'x-rays are okay' or 'gamma rays are not bad... once you get to know them'. We have just witnessed an A-bomb axplosion, but Timmy was smart enough to remember what he was taught in school: duck and cover. Good boy, Timmy! Now get back on that bicycle and go tell your parents an A-bomb just blew up near the park. It's no time to be sick on the way, Timmy... Your parents and your sister are counting on you!"

Rossum: (it was that or "birdy numnum...")

I miss Phil Hartman

 

[catlady60]

One of these really comes in handy to prevent batt venting and damage to a mech mod.

 

[beckdg]

So I guess my question after watching that venting video, do most batteries behave in a similar way? It looks like if that were a real world situation, releasing the fire button would cut off the current into the shorted section. So if I did have a short, the mech body would get hot fairly quickly, I'd probably drop it and release the fire mechanism and wait for cool down to see what actually happened. My vaping habit is to do five or six pulls in a row then set it down for a little bit, unless I'm chaining in the car. It seems like I'd know right away that there was a problem, without the loss of my hand (or face). Short happens, mech body overheats quick, drop it, let it cool and take off the atty and inspect battery/atty/switch. Does that seem to be a fairly accurate assessment?

You got it. There's also the scenario where the switch gets stuck on. If you can remove the atty and break the circuit do it. If the mods too hot just throw it somewhere it can't start a fire and retrieve it once it's cooled enough to handle.