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  1. Mechanical mods are advanced e-cigarettes that lack any kind of electronics or power output regulation. Due to their simple design and lack of safety features, mechanical mods are only recommended for experienced vapers who understand Ohm's Law and battery safety.

    Ohm's Law:

    It's very important that you understand Ohm's Law if you are using a mechanical mod. If you're not completely familiar with Ohm's Law please ready my blog post linked below:

    Ohm's Law 101 For Vapers

    Steam Engine also has a really good Ohm's Law calculator which you can access here:

    Ohm's law | Steam Engine | free vaping calculators

    Also check out this blog by Baditide:

    Ohm's Law for Dummies (Vapers)

    Battery Safety:

    Since mechanical mods lack any type of safety features, it's very important to understand battery safety concepts. We'll break it down into several key area's:

    Where To Buy:

    Only buy from a trusted store known to sell authentic high quality batteries. RTD Vapor is a highly recommended source for batteries. There are fake batteries, so avoid unknown vendors like those on eBay.

    What To Buy:

    Only buy high drain safe chemistry batteries, these are often called IMR or simply safe chemistry. Never buy protected or Lithium Ion batteries. High drain safe chemistry batteries can handle higher current loads, essential in sub ohm vaping, and if they fail, they do so in a less violent manner than Lithium Ion batteries.

    Secondly, only buy batteries that have a known maximum continuous discharge rate (CDR). A battery with a 10 amp CDR is good for 0.5-0.6 Ohm atomizers and higher. A 20 amp CDR can safely go down to 0.3-0.4 Ohms. If you're using atomizers with resistances below 0.3 Ohms a 30 amp CDR battery, like the Sony VTC4, is recommended.

    It's best to leave yourself some safety margin, as the chart below shows, current rises rapidly with sub ohm builds as resistance decreases.


    Check out Baditude's excellent blog post on batteries for more information:

    Battery Basics for Mods: IMR or Protected ICR?

    Ohm Meters:

    You need an accurate atomizer ohm meter, especially if you're using a RBA, and a digital multi meter (DMM). The dedicated atomizer ohm meter, like one from USA Ohm Meters, can give you accurate coil resistance readings. A DMM is good for checking battery voltage and checking for shorts.


    Keeping your switch, contacts, and threads clean in your mech mod is very important. Dirt and oxidation can result in high resistances that cause heat, like hot button issues. Follow your mod makers recommendations on cleaning.

    Safety Rules:

    Here are some basic safety rules to avoid problems or accidents with your mech mod:

    (1) If you press the button and it doesn't fire, STOP, remove the battery. Use your ohm meter to check for a weak battery, short, or other problem. People have vented batteries continually pressing the fire button when there was an obvious problem.

    (2) Only use quality high drain safe chemistry batteries with a sufficient CDR for the atomizer you're using. Do NOT push your batteries beyond their limits.

    (3) If the mod or battery gets hot, STOP! Remove the battery, if safe to do so, and check for shorts, oxidation or changes in atomizer resistance. Make SURE the battery you have can handle the atomizer resistance you're using.

    (4) Always test your coil builds with an ohm meter prior to using the atomizer on a mechanical mod.

    (5) ALWAYS lock the button to prevent accidental firing when carry a mechanical mod in a pocket, purse, etc...

    Please feel free to leave a comment if you have any suggestions or corrections.
  2. Knowing and understanding Ohm's Law is helpful to all vapers and essential to those running mechanical mods or using rebuildable atomizers.

    Part 1: Basic Electrical Theory

    Electricity has several measurable properties, including electrical potential (Measured in Volts), current flow (Measured in Amps), and electrical resistance (Measured in Ohms).

    Think of electricity as water flowing from a nozzle attached to a pump. The pump pressure would be equivalent to the potential, the restriction of the nozzle would be the resistance, and the amount of water flowing from the nozzle would be the current.

    In our example, if we increase the pump pressure without changing the nozzle restriction, more water will flow from the nozzle. This is equivalent to increasing the voltage supplied to an atomizer, which will result in an increase in current flow.

    Also, if our pump pressure remains stable, but we open the nozzle more, thereby decreasing the restriction, more water will flow from the nozzle. This is equivalent to using a lower resistance atomizer on a device providing a fixed voltage, resulting in more current flow.

    There are two main things to takeaway from this section:

    Point 1: If resistance is fixed, increasing voltage will increase current, and decreasing voltage will decrease current.
    Point 2: If voltage is fixed, increasing resistance will decrease current, and decreasing resistance will increase current.

    Part 2: Ohm's Law

    Ohm's Law defines the relationship between electrical potential (Measured in Volts), current flow (Measured in Amps), and electrical resistance (Measured in Ohms).

    Ohm's Law formulas typically uses the variable I to represent current in amps, V to represent potential in volts, and R to represent resistance in ohms. Ohm's Law can be stated in three ways:

    I = V / R
    R = V / I
    V = I * R

    If we know the value of two variables, we can use Ohm's Law to find the value of the third variable using the above formulas.

    Example 1:

    You have a battery with a maximum continuous discharge rate of 20 amps in your mechanical mod. You need to know if your O.5 ohm build is safe to use on this battery. Since we know more voltage causes more current, and our battery has a maximum voltage of 4.2 volts when fully charged, our maximum current flow will occur at 4.2 volts. So we use Ohm's Law:

    I = V / R
    I = 4.2 / 0.5
    I = 8.4 Amps

    So our build will draw 8.4 amps from our battery, which is well below the safe amount our battery can handle. So YES, we are safe running this setup.

    Part 3: Power (Watts)

    Power, measured in Watts, is the energy being used by your atomizer. More power generally produces more vapor, and may produce warmer vapor also.

    Power comes with its own formula, P respresenting power in Watts, which can be written in three ways:

    P = V * I
    V = P / I
    I = P / V

    Just like Ohm's Law, if we know the value of two variables, we can find the value of the third variable using the above formulas.

    Example 2:

    Your variable voltage device is set to 4.5 volts, you attach a 1.5 ohm atomizer, what power are you vaping at? First we must find current using Ohm's Law:

    I = V / R
    I = 4.5 / 1.5
    I = 3.0 Amps

    So our atomizer will draw 3.0 amps of current, now we can figure the resulting power:

    P = V * I
    P = 4.5 * 3.0
    P = 13.5 Watts

    So we are vaping at 13.5 watts using this setup.

    Part 4: Combination Formulas

    Ohm's Law and Power formulas can be combined to produce several useful formulas for vapers. These formulas can be arranged in an Ohm's Wheel:

    View attachment 414590

    Example 3:

    We can rework Example 2 using our new combination formulas. Your variable voltage device is set to 4.5 volts, you attach a 1.5 ohm atomizer, what power are you vaping at?

    P = V^2 / R
    P = 4.5^2 / 1.5
    P = 20.25 / 1.5
    P = 13.5 Watts

    So we arrived at the same answer using fewer steps than in Example 2.

    Example 4:

    You want to vape at 50 watts using your mechanical mod with a fully charged battery. What resistance coil should you put in your atomizer? We know voltage, 4.2 volts, and wattage, 50 watts, so we use a combination formula to find resistance.

    R = V^2 / P
    R = 4.2^2 / 50
    R = 17.64 / 50
    R = 0.35 Ohms

    So a 0.35 ohm build would give us 50 watts on a fully charged battery.

    Part 5: Further Reading

    Battery Specs & Safety:

    Battery Basics for Mods: IMR or Protected ICR? By Baditude

    Ohm's Law & Vaping Calculators:

    Steam Engine

    Please feel free to leave a comment if you have any suggestions or corrections.
  3. This blog post is aimed primarily at members from the USA; however, you can follow these steps anywhere you live.

    As you may already know, there is a concerted effort by powerful people, companies, and organisations out there to limit our rights to purchase, possess, and use electronic cigarettes.

    Here are 5 easy steps you can take to get involved and support our right to vape.

    STEP 1: Register To Vote

    If you can't or dont vote, you have no power. Politicians don't fear people, they fear voters. Being registered to vote is easy, free, and absolutely necessary. Rock The Vote has an easy voter registration site here:

    If you don't want to use Rock The Vote, just Google "register to vote". Register now so you're ready to vote in upcoming elections.

    STEP 2: Signup For CASAA

    It's easy and free to join CASAA and receive important Calls To Action about proposed federal, state, and local regulations. Please make sure you read the instructions on the first page at:

    Become a CASAA Member

    STEP 3: Take Action

    If you hear about proposed anti-vaping regulations, do something. Firing off some emails to your elected representatives or making a phone call only takes a few minutes of your time, but can make a world of difference.

    STEP 4: Be An Advocate

    Do what you can to spread the word about vaping rights and anti-vaping regulations. This is as simple as sharing a post on Facebook, or explaining to a friend the truth about vaping. Simple easy steps by a lot of people can make a difference.

    STEP 5: Support The Cause

    We need people in Washington and in our state capitals to work to protect our rights and fight against unreasonable regulations. We all have jobs, families, school, etc.... But by donating money to groups like CASAA we can have people out there working for us all the time. You can donate to CASAA here:

    Donate to CASAA

    I know some people will say their vote doesn't matter, or their voice doesn't matter. One vote or one voice may not make a difference, but there is power in numbers. So some of us doing something is way better than all of us doing nothing.
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