How efficient is your mech setup?

[VforVape]

Out of curiousity, I decided to see how efficient my setup was by charging the batteries to 4.2v and vaping 3.5mls, remove the batteries and put them back on the charger to see how much voltage they used. Here's my setup:

Mod: MCV Cherry Bomber, all contact points freshly polished with Autosol
tank: Zeus X dual-coil, 2x 0.4 Ni80 simple wire for a build of 0.2ohms, wicked with Muji cotton
Batteries: 2x Sony VTC5A
Charger: Nitecore D4 Digicharger
Millilitres/0.1v: 0.21875mls

I know this isn't really quite accurate, given that batteries tend to hit differently at each voltage point so please do give your inputs on how I can improve on my little experiment. Thanks!

 

[Ben85]

Not a bad experiment but until you have more comparisons, that as a result doesn’t really mean much. Would be keen to hear how you get on with different rigs, or with that mod but with a different rda for example.

You also need to fix things like airflow, have consistent wicking etc as those could affect results.

 

[Falconeer]

As a mech user - I'll be watching this thread with great interest.

Do let us know how it goes!

 

[Izan]

Out of curiousity, I decided to see how efficient my setup was by charging the batteries to 4.2v and vaping 3.5mls, remove the batteries and put them back on the charger to see how much voltage they used. Here's my setup:

Mod: MCV Cherry Bomber, all contact points freshly polished with Autosol
Tank: Zeus X dual-coil, 2x 0.4 Ni80 simple wire for a build of 0.2ohms, wicked with Muji cotton
Batteries: 2x Sony VTC5A
Charger: Nitecore D4 Digicharger
Millilitres/0.1v: 0.21875mls

I know this isn't really quite accurate, given that batteries tend to hit differently at each voltage point so please do give your inputs on how I can improve on my little experiment. Thanks!

Hi and welcome,
You may be interested in this thread on voltage drop.
How do you measure voltage drop in a mechanical mod?

Cheers
I

 

[bombastinator]

@Mooch did a bunch of videos on this entitled “minding your mechs”. Very early in his series of videos. Starts at video #2 to maybe #6? I found #2 particularly disturbing because he was having so much trouble getting consistent measurable results. Apparently doing something as simple as varying the amount of pressure used to attach an atty to the mod can drastically affect resistance and in turn what power level you are vaping at. Goes to allowing room for slop into your build on a mech as it may not actually be the level you think it is.

 

[t8kiteasy]

Out of curiousity, I decided to see how efficient my setup was by charging the batteries to 4.2v and vaping 3.5mls, remove the batteries and put them back on the charger to see how much voltage they used. Here's my setup:

Mod: MCV Cherry Bomber, all contact points freshly polished with Autosol
Tank: Zeus X dual-coil, 2x 0.4 Ni80 simple wire for a build of 0.2ohms, wicked with Muji cotton
Batteries: 2x Sony VTC5A
Charger: Nitecore D4 Digicharger
Millilitres/0.1v: 0.21875mls

I know this isn't really quite accurate, given that batteries tend to hit differently at each voltage point so please do give your inputs on how I can improve on my little experiment. Thanks!

A little off topic but how did you eliminate the cherry bombers auto fire problem to get an accurate read ??
Or did you fix the auto fire problem??

 

[sonicbomb]

The voltage drop just within an unregulated device will increase exponentially the lower the coil resistance. The point is that any measurement of a device is only relevant for comparison if you use exactly the same coil. Also this method does not take into account the battery's internal resistance or voltage drop. So unless you are able to measure this value independently what you will get is the sum voltage drop of that device, at that resistance, with that particular battery.

You can measure the voltage drop by putting a resistance/volt meter across the positive and negative posts of a setup, loaded with a coil as it needs to be measured under load. Measure the voltage and subtract it from the voltage that was in the battery. The difference is the voltage drop.

eg.

Stingray x clone loaded with dual coils at 0.25 ohms

Battery voltage 4.2 volts
Measured voltage 3.68 volts
Voltage drop 0.52 volts

Using Ohms law this setup produces a theoretical 70 watts, what you actually get at the coil is 54 watts.
This equates to a 77% efficiency which in my experience is really good for a mech.

 

[dom qp]

The voltage drop just within an unregulated device will increase exponentially the lower the coil resistance. The point is that any measurement of a device is only relevant for comparison if you use exactly the same coil. Also this method does not take into account the battery's internal resistance or voltage drop. So unless you are able to measure this value independently what you will get is the sum voltage drop of that device, at that resistance, with that particular battery.

You can measure the voltage drop by putting a resistance/volt meter across the positive and negative posts of a setup, loaded with a coil as it needs to be measured under load. Measure the voltage and subtract it from the voltage that was in the battery. The difference is the voltage drop.

eg.

Stingray x cone loaded with dual coils at 0.25 ohms

Battery voltage 4.2 volts
Measured voltage 3.68 volts
Voltage drop 0.52 volts

Using Ohms law this setup produces a theoretical 70 watts, what you actually get at the coil is 54 watts.
This equates to a 77% efficiency which in my experience is really good for a mech.

I need to buy a voltmeter. 23% loss is pretty staggering. That has huge implications on builds and battery safety.

I build my mech coils on regulated mods using ~3.7V to see how it would hit after voltage drop. Seems pretty similar in my experience and that seems to be pretty similar to the results you got with the stingray.

 

[sonicbomb]

<deleted>

 

[bombastinator]

I like to get to the coil what I dial-in, and for it to stay there. It's why I don't use mechs anymore.
Also I like to vape around 70 watts and getting that on a single battery mech is an exercise in frustration. The losses are ridiculous and it means using a battery with a very low mAh rating.

Oooh! Oooh! Totally non-topical, but @Lordron's_Drag found a drip tip with a picture of you on it. “D” I believe. Why has no one told me of this??!?!

 

[sonicbomb]

Oooh! Oooh! Totally non-topical, but @Lordron's_Drag found a drip tip with a picture of you on it. “D” I believe. Why has no one told me of this??!?!

That's not me, you know we're clones right?

 

[MacTechVpr]

@Mooch did a bunch of videos on this entitled “minding your mechs”. Very early in his series of videos. Starts at video #2 to maybe #6? I found #2 particularly disturbing because he was having so much trouble getting consistent measurable results. Apparently doing something as simple as varying the amount of pressure used to attach an atty to the mod can drastically affect resistance and in turn what power level you are vaping at. Goes to allowing room for slop into your build on a mech as it may not actually be the level you think it is.

Nahhh, you just didn't say that.

Tehnsioned Contact Micro Coil, MacTechVpr

• MacTechVpr
• Jun 25, 2015
• coil contact tensioned

Good luck.

 

[bombastinator]

Nahhh, you just didn't say that.

Tehnsioned Contact Micro Coil, MacTechVpr

• MacTechVpr
• Jun 25, 2015
• coil contact tensioned

Good luck.

I did think mooch said that, and I did disturb me. I was corrected by @sonicbomb and it’s not quite as bad as I thought apparently. Still don’t like it much.

 

[sonicbomb]

The RX Machina responded well to a good mash

 

[bombastinator]

The RX Machina responded well to a good mash

Or to a no less than perfect one anyway. The difference between perfect and not quite perfect was like 50%. I need to watch that whole series end to end again.

 

[suprtrkr]

I have a simpler outlook on life. I don't build anywhere near the limits, and I measure my mech efficiency by the vape I get.

Of course, I also don't have a milliohmmeter. If I did, I'd probably measure it within an inch of its life.

Call me Old Skool...

 

[Walee]

I've only tested one mod in a similar fashion. I measured the voltage across the batteries at the same time I measured the voltage across the coil while firing the device. This was a simple device with only a mosfet. The voltage developed across the mod+atty was negligible. The difference between batteries under load however varied greatly. I apologize but it's been a minute since I did the test and don't remember any specifics regarding measurements.

 

[MacTechVpr]

I did think mooch said that, and I did disturb me. I was corrected by @sonicbomb and it’s not quite as bad as I thought apparently. Still don’t like it much.

Perhaps your instincts aren't as wrong as you think. And I posted a t.m.c. to validate you and affirm the proposition that uniformity is the solution. A classic tell for me looking at a lot of high mass coils which when oxidized are uniform in end turn color. When this happens they're often gold which to me suggests very high temp relative to the rest of the coil. Obviously the makers think they've wound/installed a great build. And it's going to vape at a temp commensurate to mass. However, those outbound segments will likely go disproportionately hot, as they did when they were oxidized in burn in. The point being pressure (or strain) applied in installation certainly created the imbalance in those segments no matter how pretty it played inside-out. But we don't ordinarily watch our winds in operation.

My criticism here is about some of the assumptions made about proper installation and as you say, the pressure applied.

Good luck.

p.s. Do see now the [contact] pressure being talked about in the video. Had been quite a while since I'd seen it.

 

[VforVape]

A little off topic but how did you eliminate the cherry bombers auto fire problem to get an accurate read ??
Or did you fix the auto fire problem??

To eliminate the auto-firing issue you just have to paint the area around the atomizer but I got the black painted box so there's no auto-fire issue in my case. There are tons of videos out there describing the auto-fire issue and how to solve it, so do go search if you're looking for a solution.

 

[VforVape]

The voltage drop just within an unregulated device will increase exponentially the lower the coil resistance. The point is that any measurement of a device is only relevant for comparison if you use exactly the same coil. Also this method does not take into account the battery's internal resistance or voltage drop. So unless you are able to measure this value independently what you will get is the sum voltage drop of that device, at that resistance, with that particular battery.

You can measure the voltage drop by putting a resistance/volt meter across the positive and negative posts of a setup, loaded with a coil as it needs to be measured under load. Measure the voltage and subtract it from the voltage that was in the battery. The difference is the voltage drop.

eg.

Stingray x clone loaded with dual coils at 0.25 ohms

Battery voltage 4.2 volts
Measured voltage 3.68 volts
Voltage drop 0.52 volts

Using Ohms law this setup produces a theoretical 70 watts, what you actually get at the coil is 54 watts.
This equates to a 77% efficiency which in my experience is really good for a mech.

Gee I had no idea vdrop would be so massive on mechs.. guess it's time to get a suitable resistance/volt meter that would fit across the +ve/-ve posts of my setup and see how it performs. I think I've seen vdrop in action though, but on my CoilMaster Tab V2 ohm meter when firing a build on it. Eg. the voltage will start out at 3.89 on the digital readout but drop to 3.14 when the fire button is pressed. I guess it's to be expected, given that it's just a ....ty protected mod.