Help with first mech mod

[Centauri]

Hello dudes,

I'm thinking of getting my first mech mod.
I have a question though regarding the safety aspect.
Am I right in that when using an ohm calculator that I need to enter the resistance of the coil I'll be using and then the voltage of the battery, and then the amperage and wattage I'm given as a result is the amount that I need to make sure that my battery can handle?

My understanding is that a 21700 battery is 3.6v. So if I am using an 0.11ohm coil the amperage will be 32.73 and the wattage 117.82.
I use Molicel P45B which has a max current discharge rate of 45A and 184w (according to Molicel's product page here).

So as long as the amp current and wattage I'm given by the calculator is with in the ability of the battery, then I am safe. Is that right?
Is that basically how it works?

I know about getting it all set up on a regulated mod first to make sure the ohm reading is correct etc but just wanted to check the above.

Finally, if anyone can recommend any affordable 21700 mech mods for a first timer I'd appreciate that. Been looking at the Timesvape Heavy Hitter mech mod as it looks nice and is very affordable.

Thanks in advance.

 

[Sir Kadly]

Hello dudes,

I'm thinking of getting my first mech mod.
I have a question though regarding the safety aspect.
Am I right in that when using an ohm calculator that I need to enter the resistance of the coil I'll be using and then the voltage of the battery, and then the amperage and wattage I'm given as a result is the amount that I need to make sure that my battery can handle?

My understanding is that a 21700 battery is 3.6v. So if I am using an 0.11ohm coil the amperage will be 32.73 and the wattage 117.82.
I use Molicel P45B which has a max current discharge rate of 45A and 184w (according to Molicel's product page here).

So as long as the amp current and wattage I'm given by the calculator is with in the ability of the battery, then I am safe. Is that right?
Is that basically how it works?

I know about getting it all set up on a regulated mod first to make sure the ohm reading is correct etc but just wanted to check the above.

Finally, if anyone can recommend any affordable 21700 mech mods for a first timer I'd appreciate that. Been looking at the Timesvape Heavy Hitter mech mod as it looks nice and is very affordable.

Thanks in advance.

You have the basic principle correct, however a fully charged battery will output 4.2 volts. Granted it doesn't maintain that voltage for long, but your calculations should always be based on 4.2v. Looks like that comes out to 38.18 amps.

 

[zoiDman]

...

So as long as the amp current and wattage I'm given by the calculator is with in the ability of the battery, then I am safe. Is that right?
Is that basically how it works?

...

Yes... That is Basically how it works. With a Few Caveats.

The First thing is NEVER use a Battery's "Max" or "Peak" Current Rating in you evaluation. You have to use the "Constant Discharge Rate", CDR, for the battery. The CDR will always be substantially Lower than the Max Current Discharge.

You also need to give yourself a little "Headroom" when you consider how many amps your build will pull from your Battery. And what a Batteries CDR is as reported by the OEM.

In a Perfect World, all Math Calculations would jive to observation withing 27 Decimal places. But we know that this Isn't the Real World. In the Real World, things like Ohm Meters have some degree of Error. Batteries wear down from use of from being dropped. And it Isn't Unheard of to have an OEM Optimistically Inflate a spec in the hopes of making their Battery look better that their competitors.

So after you do an Amp Draw Calculation, give yourself a little room to the Safer side (10 ~ 15%) to take into account factors you might not perceive that are effecting your numerical Bottom Line.

I also would recommend that keep your Mech Clean and check it Regularly for any signs that there might be a problem.

There is a Purity to using a Mech. And they, with the Proper Care, can Out Live You. But they Demand that a Person understands that they can Harm You. And that you need to be Attentive Every Time You Use One.

 

[Centauri]

I've read the report Mooch made on the P45B. He said the P45B has a "35A continuous and a 45A temperature-limited rating".
Given vaping is only 2-3 second bursts of battery use, is it safe to say that the battery won't get to such temps as to make the amp draw limited & I can rely on a 45A draw or should I base it on 35A?

Here is his report on the P45B

32.73A is not very far off 35A so maybe it would be better going for a higher resistance coil on my first mech mod to be safe.


Am I also right that when using a mech mod, suddenly the vapour production will get poor and that is a sign that the voltage has dropped and you should swap them out?
Obviously you don't want to run a battery too low or you can ruin it, but am I to expect a sudden loss of vapour production as a sign that it needs changing/charging?

 

[zoiDman]

I've read the report Mooch made on the P45B. He said the P45B has a "35A continuous and a 45A temperature-limited rating".
Given vaping is only 2-3 second bursts of battery use, is it safe to say that the battery won't get to such temps as to make the amp draw limited & I can rely on a 45A draw or should I base it on 35A?

Here is his report on the P45B

32.73A is not very far off 35A so maybe it would be better going for a higher resistance coil on my first mech mod to be safe.


Am I also right that when using a mech mod, suddenly the vapour production will get poor and that is a sign that the voltage has dropped and you should swap them out?
Obviously you don't want to run a battery too low or you can ruin it, but am I to expect a sudden loss of vapour production as a sign that it needs changing/charging?

Always Use the Continuous Discharge Rating.

A build that draws 32.7 Amps from that Battery is at the High End, but I would consider it fine. You are using the CDR and You have some Safety Margin.

---

Actually, when you use a Mech, the Vapor production and the Flavor tend to Fall-Off slowly. Trust me, You don't have to worry about not knowing your Batteries are reaching a Low Voltage. You'll know from the Taste. And it would surprise me if you were using one below 3.4 or 3.2 Volts. Which is Fine for the type of Batteries we use.

 

[zoiDman]

Always Use the Continuous Discharge Rating.

A build that draws 32.7 Amps from that Battery is at the High End, but I would consider it fine. You are using the CDR and You have some Safety Margin.

---

Actually, when you use a Mech, the Vapor production and the Flavor tend to Fall-Off slowly. Trust me, You don't have to worry about not knowing your Batteries are reaching a Low Voltage. You'll know from the Taste. And it would surprise me if you were using one below 3.4 or 3.2 Volts. Which is Fine for the type of Batteries we use.

BTW - When I first started to use a Mech, I had like 3 Different Battery types all with Different CDR's. So I would do the Math for what I considered to be the Highest Amp Draw I felt was OK for an individual battery. Then I wrote the Amp Amount on the Battery Wrap and covered it with a piece of Clear Tape.

That way I could tell at a Glance just what the Battery could handle for a given build.

Something to consider if you are using Different Types of Batteries.

 

[somdcomputerguy]

32.73A is not very far off 35A so maybe it would be better going for a higher resistance coil on my first mech mod to be safe.

Am I also right that when using a mech mod, suddenly the vapour production will get poor and that is a sign that the voltage has dropped and you should swap them out?

The coils I wrap (between 1 and 2 ohms) have never asked for more than 2 or 3 Amps from a battery. I would probably be safe using batts with a 10A CDS rating, but all mine are in the 20, 25+ ballpark and I just wouldn't feel comfortable using anything less. I would certainly suggest that you use a higher resistance coil.

As the battery loses power, the whole 'vape essence' thing changes as well. I honestly don't think you'll 'see' sudden changes though. That's one of the things I like most about my mech.

​

 

[Centauri]

The coils I wrap (between 1 and 2 ohms) have never asked for more than 2 or 3 Amps from a battery. I would probably be safe using batts with a 10A CDS rating, but all mine are in the 20, 25+ ballpark and I just wouldn't feel comfortable using anything less. I would certainly suggest that you use a higher resistance coil.

As the battery loses power, the whole 'vape essence' thing changes as well. I honestly don't think you'll 'see' sudden changes though. That's one of the things I like most about my mech.

​

I vape direct lung so the coils I use are between 0.07 and 0.20 for dual coils.
Obviously 0.07 really wouldn't be suitable for a mech but I will try to aim for higher resistance coils such as 0.15+. I don't vape MTL though so 1.0+ isn't for me.
Right now I'm on a Dovpo Blotto Max with two handmade 6 core Ni80 aliens. They're AMAZING coils and the flavour is excellent. Resistance on my Odin V2 is showing as 0.10ohm. Obviously I'll need to find other coils for the mech mod, or even get a single coil RTA. I really love these coils though.
Here is a close up of one of them.
Your mod looks nice though. It has a look of sophistication XD


@Sir Kadly So what is the deal with saying a 21700 battery has 4.2v? The product page for the P45B say it's voltage is 3.6 and other info I've seen also says 3.6v. Though I did find one place that also said 4.2v but most say 3.6.
Can you please explain that?

 

[Sir Kadly]

I vape direct lung so the coils I use are between 0.07 and 0.20 for dual coils.
Obviously 0.07 really wouldn't be suitable for a mech but I will try to aim for higher resistance coils such as 0.15+. I don't vape MTL though so 1.0+ isn't for me.
Right now I'm on a Dovpo Blotto Max with two handmade 6 core Ni80 aliens. They're AMAZING coils and the flavour is excellent. Resistance on my Odin V2 is showing as 0.10ohm. Obviously I'll need to find other coils for the mech mod, or even get a single coil RTA. I really love these coils though.
Here is a close up of one of them.
Your mod looks nice though. It has a look of sophistication XD


@Sir Kadly So what is the deal with saying a 21700 battery has 4.2v? The product page for the P45B say it's voltage is 3.6 and other info I've seen also says 3.6v. Though I did find one place that also said 4.2v but most say 3.6.
Can you please explain that?

3.6 is the nominal voltage, essentially battery voltage ratings were originally developed by measuring voltage output when fully charged, then voltage output at the battery cutoff point and averaging them. So theoretically the 3.6v rating means that during the time period between fully charged and fully discharged the battery will average 3.6v output.

The fully charged output though is higher. For 18650, 20700, 21700, etc this is 4.2v, with most of them showing a nominal rating of either 3.6 or 3.7v.

 

[Centauri]

3.6 is the nominal voltage, essentially battery voltage ratings were originally developed by measuring voltage output when fully charged, then voltage output at the battery cutoff point and averaging them. So theoretically the 3.6v rating means that during the time period between fully charged and fully discharged the battery will average 3.6v output.

The fully charged output though is higher. For 18650, 20700, 21700, etc this is 4.2v, with most of them showing a nominal rating of either 3.6 or 3.7v.

Ok that makes sense. Thanks for explaining

 

[Centauri]

Oh one other thing.
I don't know what the term is for the opposite of a hybrid connection. But I know there's a proper 510 and then a hybrid one where the tank comes into contact with the battery.
Ultimately what is the difference between the two? Does the full hybrid one ramp up faster because of the lack of metal between the contacts or something?
I've noticed that many of the mech mods have a hybrid connection. As a mech noob should i avoid that?

Edit: also, if I get a dual battery one should I aim for a parallel connection to double the amps?

 

[ShowMeTwice]

I have a question though regarding the safety aspect.

Always make sure your battery wraps Do Not have any tears or other damage. Failure to check = BOOM.

I don't know what the term is for the opposite of a hybrid connection. But I know there's a proper 510 and then a hybrid one where the tank comes into contact with the battery.
Ultimately what is the difference between the two?

A non-hybrid traditional mech has an adjustable 510 pin for the RBA and a screw to adjust for battery fit.

Like so........

That photo is from my authentic King mech, posted for someone else in another thread who had some questions about King mechs. The screw above the battery adjustment screw raises/lowers the 510 pin for RBA fitment.

And...... that's the only visual difference between a traditional tube mech and a hybrid.

Hybrid mechs hit harder and there is a lower voltage drop.

I have and regularly use several of each style.

Are hybrid mechs safe for a noob? Yes and No.

If said noob is not careful, then no. If the noob has done their due diligence (homework), then yes.
Although, I would say the same for a noob using a non-hybrid mech.


With a hybrid mech you always want to install the RBA <<< BEFORE >>> inserting the battery.

On a hybrid mech you MUST make sure whatever RBA is being used has a 510 pin that protrudes past the negative.

If the 510 pin is flush and you install a battery ---> BOOM.

this will help.........

Here are some of the RBA's I -- safely -- use on my mechs. See how the 510 pins protrude from the negative? Make certain your RBA looks like those! If your 510 pin is flush - - - Do Not Use It on a Hybrid Mech - - - or BOOM!!!

Also, do not adjust the 510 pin on your RBA. It should be screwed down tight - but not so tight that it damages the insulator.

While I'm on the subject of insulators, you should periodically remove the RBA 510 pin to check the integrity of the insulator. Never ( NEVER ) use an RBA that has a cracked or damaged insulator.


The Only Safety When Using a Mech ---> Sits Between Your Ears. The Brain.

And a good functional brain that fully understands Ohms Law, keeps their mech and threads clean and inspects batteries for damage before use. Also, one should always build and thoroughly test their RBA on a regulated mod before putting it on a mech. Common Sense!

Also, I never build below 0.5Ω on any mech. I tried at 0.2Ω once and my personal thoughts are, no one needs to build that low. But, do with that whatever you will. I know several "very VERY experienced" mech users who do build down to 0.15Ω --- and well, to each their freakin' own.

Personally, as a NOOB -- I would not start out with a build lower than 0.5Ω. Think Safety and Gaining Experience with a Mech First. Once one fully understands what their getting into, and has some experience with a mech, then, sure go lower, if that's your thing.

Good luck with whatever you decide to do.

Hope that helps!


ETA: Also make sure to clean the 510 threads on your RBA.

 

[Centauri]

Always make sure your battery wraps Do Not have any tears or other damage. Failure to check = BOOM.



A non-hybrid traditional mech has an adjustable 510 pin for the RBA and a screw to adjust for battery fit.

Like so........

View attachment 1006562
That photo is from my authentic King mech, posted for someone else in another thread who had some questions about King mechs. The screw above the battery adjustment screw raises/lowers the 510 pin for RBA fitment.

And...... that's the only visual difference between a traditional tube mech and a hybrid.

Hybrid mechs hit harder and there is a lower voltage drop.

I have and regularly use several of each style.

Are hybrid mechs safe for a noob? Yes and No.

If said noob is not careful, then no. If the noob has done their due diligence (homework), then yes.
Although, I would say the same for a noob using a non-hybrid mech.


With a hybrid mech you always want to install the RBA <<< BEFORE >>> inserting the battery.

On a hybrid mech you MUST make sure whatever RBA is being used has a 510 pin that protrudes past the negative.

If the 510 pin is flush and you install a battery ---> BOOM.

this will help.........

View attachment 1006567

Here are some of the RBA's I -- safely -- use on my mechs. See how the 510 pins protrude from the negative? Make certain your RBA looks like those! If your 510 pin is flush - - - Do Not Use It on a Hybrid Mech - - - or BOOM!!!

View attachment 1006563

Also, do not adjust the 510 pin on your RBA. It should be screwed down tight - but not so tight that it damages the insulator.

While I'm on the subject of insulators, you should periodically remove the RBA 510 pin to check the integrity of the insulator. Never ( NEVER ) use an RBA that has a cracked or damaged insulator.


The Only Safety When Using a Mech ---> Sits Between Your Ears. The Brain.

And a good functional brain that fully understands Ohms Law, keeps their mech and threads clean and inspects batteries for damage before use. Also, one should always build and thoroughly test their RBA on a regulated mod before putting it on a mech. Common Sense!

Also, I never build below 0.5Ω on any mech. I tried at 0.2Ω once and my personal thoughts are, no one needs to build that low. But, do with that whatever you will. I know several "very VERY experienced" mech users who do build down to 0.15Ω --- and well, to each their freakin' own.

Personally, as a NOOB -- I would not start out with a build lower than 0.5Ω. Think Safety and Gaining Experience with a Mech First. Once one fully understands what their getting into, and has some experience with a mech, then, sure go lower, if that's your thing.

Good luck with whatever you decide to do.

Hope that helps!


ETA: Also make sure to clean the 510 threads on your RBA.

Yes I am doing my homework on it before I get one. Watching Youtube videos on mech's and how to safely use them, and of course asking questions here.
I regularly check my batteries for damage as I charge them externally so I'm basically handling them every day. One of the things I first learnt was about the protruding pin. Mike Vapes always made a comment about the pin protruding on the RTA/RBA he was reviewing enough for a hybrid mech mod and I wondered what he meant by that. That is when my interest in mechs first started.

But yes I am preparing myself and educating myself on them.


As I said earlier my dual coil build comes out between 0.07ohm & 0.11 depending on what RTA I use & if I need an extra wrap or not. I use dual coil 6 core ni80 aliens and they're the best coils I've tried so far, but also as I said I know that I can't use these on a mech and will need to change coils to have a higher resistance. I've not purposefully gone for 0.07, it's just the flavour from these coils is amazing and they just so happen to come out at 0.07.
I will buy some other coils especially for the mech when I get it so that I'm safe.
But thanks for the advice.

 

[Centauri]

One other unrelated question, and sorry if I need to create another thread for this...

But in regards to coil stats. I know for example that a 6x30/36 means the coil has 6 cores of 30 gauge which is wrapped in a 36 gauge. But what does 8-.1*.3/36 mean? I see the last 36 is likely the wrap, but what does that mean before it? I see that kind of coil stat often. Is it in reference to a ribbon wire? Can someone please explain?
Thanks

 

[Centauri]

Anyone able to help me out with the question in the last post please?

I just got myself a really cheap mech squonk mod. The Wotofo Nudge. Just something to for me to try out before I get a better one. The only RDA I have is dual coil and I'm having a hard time finding coils of the right resistance that aren't like single core MTL coils. It's a single 18650 battery mod & I'm using a Molicel P42A battery. It has enough amps for the coils I have, but the battery doesn't have enough wattage output for the coils I have. If I'm not mistaken I'm limited by 80w on that battery.

 

[englishmick]

3.6 is the nominal voltage, essentially battery voltage ratings were originally developed by measuring voltage output when fully charged, then voltage output at the battery cutoff point and averaging them. So theoretically the 3.6v rating means that during the time period between fully charged and fully discharged the battery will average 3.6v output.

The fully charged output though is higher. For 18650, 20700, 21700, etc this is 4.2v, with most of them showing a nominal rating of either 3.6 or 3.7v.

Great, thanks. All these years I never knew where the 3.6 came from. Never cared enough to find out I guess.

 

[Rossum]

It's a single 18650 battery mod & I'm using a Molicel P42A battery.

The P42A is a 21700. How do you fit that into a single 18650 battery mod?

my dual coil build comes out between 0.07ohm & 0.11

IMO, that's excessively low for a single-cell mech mod. You probably won't blow anything up, but the battery will not be happy for very long.