How Do I Keep My Builds Consistent

[hadewwken]

Got a question about my coils. I abide by the basics of building. Currently am building on my Praxis v2 while using Sony Vtc4's. I always making sure my batteries are charged before building and I always always always check my ohms while building with my ohm reader.

I have just been having trouble with keeping my builds consistent. Lately I have been rocking a dual coil, 4/5 wrap on 1/8" drill bit (always wrap on this size btw), 22 gauge, reading at 0.18 ohms (lowest resistance I will ever vape at). Building these coils and having them fire up consistently (power-wise) hasn't been a problem. They have always came out satisfying for me. Previously, however, when I use to be parallel crazy with my coils, I'd be building only with the hope that I would come out with a decent coil. Usually with these builds, I'd go single coil, 5/6 wrap, usually ranging from 0.32 ohms to 0.4. Despite the consistency in my resistance, I find that the ramp up time for my coils would always vary from slow to perfect. It was always a hit or a miss situation when I built these coils and would always be tearing out coils and putting in new ones till I got it right. I've been getting a little tired of the hot hot vape from the 22 gauge and I want to slap some 24 or 26 gauge back in my Samurai.

My question here is, how do I avoid a slow ramp up time for my builds and how do I keep them consistently good? Is it actually just a luck thing like how I described it ^ or is there something I'm not doing right?

Any advice is appreciated.

Thanks ECF

Also, since I am already posting this, got another question. I tried building a 22 gauge, 4/5 wrap dual sleeper coil reading at .19 today but when I was test firing, the wire trapped under the screw in the positive post kept glowing red hot and so I quickly pulled out the entire coil in fear of the what could happen. Is that what a short looks like or was it just something bad with the connection? I always make sure nothing glows red hot when test firing with wick and juice installed but never got to that point with that build. What might have happened here?

 

[Katmar]

I don't build, but I sure can bump this post up and hope you get an answer!!!!

Welcome and Happy Vaping!!

 

[Bunnykiller]

consistancy? regulated mod...

 

[Sgt.Rock]

Regulated mods won't cure unevenly heating coils or "hot legs".

Adjusting them after firing with tweezers or needle nose pliers may however...make sure not to fire while adjusting. Sometimes a slight squeeze is all it takes.

 

[BigCatDaddy]

Pulse, squeeze, pulse squeeze, pulse squeeze until they even out. No biggie!!

 

[Frenchfry1942]

I...pulse, squeeze, pulse, squeeze. The tighter I get the coil as a micro coil, the higher the ohms will be. It is a small amount, maybe a single ohm, but it does give me some flexibility as to the ohms I want. Some ohms readers are now registering to the hundredths of an ohm.

I, also, understand that readers can e off a tad. Life goes on...

 

[dice57]

For me it was with tension wrapped coils. Using a wire coiling gizmo, using tension wrapping. Makes for purrfect coils every time

​

Some time a pulse and a squeeze is necessary, but rarely.

 

[readeuler]

Got a question about my coils. I abide by the basics of building. Currently am building on my Praxis v2 while using Sony Vtc4's. I always making sure my batteries are charged before building and I always always always check my ohms while building with my ohm reader.

I have just been having trouble with keeping my builds consistent. Lately I have been rocking a dual coil, 4/5 wrap on 1/8" drill bit (always wrap on this size btw), 22 gauge, reading at 0.18 ohms (lowest resistance I will ever vape at). Building these coils and having them fire up consistently (power-wise) hasn't been a problem. They have always came out satisfying for me. Previously, however, when I use to be parallel crazy with my coils, I'd be building only with the hope that I would come out with a decent coil. Usually with these builds, I'd go single coil, 5/6 wrap, usually ranging from 0.32 ohms to 0.4. Despite the consistency in my resistance, I find that the ramp up time for my coils would always vary from slow to perfect. It was always a hit or a miss situation when I built these coils and would always be tearing out coils and putting in new ones till I got it right. I've been getting a little tired of the hot hot vape from the 22 gauge and I want to slap some 24 or 26 gauge back in my Samurai.

My question here is, how do I avoid a slow ramp up time for my builds and how do I keep them consistently good? Is it actually just a luck thing like how I described it ^ or is there something I'm not doing right?

Any advice is appreciated.

Good question! Coil ramp-up time is related to two things: The wattage applied to the atomizer, and the total mass of metal that you've got to heat up. Thankfully, there's a very very good calculator that can help you get a handle on whether a build will heat up sufficiently quickly. Here's a great blog post by State O' Flux on two important parameters: http://www.e-cigarette-forum.com/fo...ne-basic-use-advanced-features-part-deux.html

Let's look at your build on Steam Engine.

Some pertinent stats
Wattage: 80W
Coil mass: 184mg
Heat Capacity: 86 mJ/K
Heat Flux: 245 mW/mm^2

So, these are some pretty hefty coils. But the good news, as far as lag goes, is that you're hitting them with a comparably high wattage, 80 watts assuming the atomizer gets hit with 3.8 volts after voltage drop (I think that's a pretty reasonable voltage drop with the incredibly low load of 0.18 ohms, but maybe you can whip out a multimeter to see what it actually is).

The mass/heat flux is a big part of the equation. The heat flux is just a measure of how much energy (measured in Joules = watt seconds) you need to raise the temperature of the coil by 1 Kelvin = 1 degree Celsius = 1.8 degrees Fahrenheit, and it's proportional to the mass of the coils.

Now, all these numbers are kind of meaningless in a vacuum, but if you compare the stats for different builds, you can get a sense of what works. The above build works, as does mine:

Here's my build on Steam Engine.

The stats
Wattage: 40W
Coil mass: 77mg
Heat Capacity: 35.45 mJ/K
Heat Flux: 148 mW/mm^2

So, let's look at some ratios. For your build, the ratio of Wattage to Heat capacity is around 80/85 ~ 0.94. For my build, the ratio is around 40/35 ~ 1.14. So as long as your wattage is pretty close to, or exceeds, the heat capacity, things look good.

Another ratio: For your build, the ratio of Heat Flux to Heat Capacity is 245/85 ~ 2.88. For my build, this ratio is 145/35 ~ 4.14. So it looks like as long as your heat flux is about 3 times as much as the Heat capacity, things will work out well.

I would try to go and plug some of your old builds into Steam Engine, to see how the numbers/ratios look. I bet you'll find that for the ones that took too long to heat, these ratios were out of sync; too much heat capacity for the power.

Also, since I am already posting this, got another question. I tried building a 22 gauge, 4/5 wrap dual sleeper coil reading at .19 today but when I was test firing, the wire trapped under the screw in the positive post kept glowing red hot and so I quickly pulled out the entire coil in fear of the what could happen. Is that what a short looks like or was it just something bad with the connection? I always make sure nothing glows red hot when test firing with wick and juice installed but never got to that point with that build. What might have happened here?

That sounds like a hot leg. Aside from dry burning and pinching the coils together, Super X had a great suggestion of running something metallic length-wise through the coils. It'll make kind of a grating 'nails on chalkboard' sound, but it really fixes hot legs; I don't know why. I try to always heat up my brand new coils without wick, to see how they look. Hot legs will give you terrible burnt tastes, and forgetting to eliminate them just got me the other day, in fact.

 

[drunkenbatman]

dice57 & Redeuler have you covered, as I was just going to mention the importance that tension can play in consistency once the coils start firing and oxidizing. I use a little jig that helps with it, but it doesn't have to be a specific gizmo -- before that I was using two screwdrivers, as you can accomplish a lot by wrapping the loose end of a piece of kanthal around something and pinching it so you can pull as you wrap around something.

 

[hadewwken]

Wow just woke up to see the post lol thank you everyone for all your tips! I really appreciate it, I think I'll give it another go with 24 gauge today and will let yall know how it went. Thanks again everyone

 

[HecticEnergy]

Good question! Coil ramp-up time is related to two things: The wattage applied to the atomizer, and the total mass of metal that you've got to heat up. Thankfully, there's a very very good calculator that can help you get a handle on whether a build will heat up sufficiently quickly. Here's a great blog post by State O' Flux on two important parameters: http://www.e-cigarette-forum.com/fo...ne-basic-use-advanced-features-part-deux.html

Let's look at your build on Steam Engine.

Some pertinent stats
Wattage: 80W
Coil mass: 184mg
Heat Capacity: 86 mJ/K
Heat Flux: 245 mW/mm^2

So, these are some pretty hefty coils. But the good news, as far as lag goes, is that you're hitting them with a comparably high wattage, 80 watts assuming the atomizer gets hit with 3.8 volts after voltage drop (I think that's a pretty reasonable voltage drop with the incredibly low load of 0.18 ohms, but maybe you can whip out a multimeter to see what it actually is).

The mass/heat flux is a big part of the equation. The heat flux is just a measure of how much energy (measured in Joules = watt seconds) you need to raise the temperature of the coil by 1 Kelvin = 1 degree Celsius = 1.8 degrees Fahrenheit, and it's proportional to the mass of the coils.

Now, all these numbers are kind of meaningless in a vacuum, but if you compare the stats for different builds, you can get a sense of what works. The above build works, as does mine:

Here's my build on Steam Engine.

The stats
Wattage: 40W
Coil mass: 77mg
Heat Capacity: 35.45 mJ/K
Heat Flux: 148 mW/mm^2

So, let's look at some ratios. For your build, the ratio of Wattage to Heat capacity is around 80/85 ~ 0.94. For my build, the ratio is around 40/35 ~ 1.14. So as long as your wattage is pretty close to, or exceeds, the heat capacity, things look good.

Another ratio: For your build, the ratio of Heat Flux to Heat Capacity is 245/85 ~ 2.88. For my build, this ratio is 145/35 ~ 4.14. So it looks like as long as your heat flux is about 3 times as much as the Heat capacity, things will work out well.

I would try to go and plug some of your old builds into Steam Engine, to see how the numbers/ratios look. I bet you'll find that for the ones that took too long to heat, these ratios were out of sync; too much heat capacity for the power.



That sounds like a hot leg. Aside from dry burning and pinching the coils together, Super X had a great suggestion of running something metallic length-wise through the coils. It'll make kind of a grating 'nails on chalkboard' sound, but it really fixes hot legs; I don't know why. I try to always heat up my brand new coils without wick, to see how they look. Hot legs will give you terrible burnt tastes, and forgetting to eliminate them just got me the other day, in fact.

This^

I use 28ga mostly because I want more battery life and good ramp up time. I also mostly prefer flavor over hefty clouds. I do around Net .8ohms on my dual coils or 1.2-1.6 on my single coils. I generally use 3/32 ID though sometimes 5/64 or 7/64 depending on wire gauge and what my target build is at. much smaller than that and the wire is too much of a PITA to work with IMO. (29ga would probably be fine, but I've got some 32ga that is super thin and way too springy.
For clouds I build around Net .2ohm duals with 24ga or .4ohm duals with 26ga (3/32 or 7/64 ID)
I dont use a jig or anything, but I keep tention on the wire by hand as I'm wrapping it - Pinch one end of the lead between your thumb and the drill bit, grab the other end of the wire tightly, leaving about a foot or two between where you hold it with your free and and the end pinched against the drill bit. Pull tight and wrap. As you wrap, the hand doing the wrapping (not the drill bit hand) should not be perfectly perpendicular to the drill bit after the first wrap. Lean it toward the coil a bit. keeping tension on the wire as you wrap will keep your wraps from over lapping, but will make sure they are right next to each other. If I want to tighten it down more, I'll grab a pair of plyers and pull the leads (both at the same time) while the coil is still on the rod. That, or mount the coil and pull the rod away from the posts (seems like unnecessary wear and tear on the atty IMO). I use this method to wrap parallel coils do and they seem to come out easier.
I've read that the pinch pulse method causes extra wear on attys (especailly clones with low quality insulators) so I have been torching my coils while they are pinched in some tweezers (26 or 18ga) or a pair of pliers( 24ga). Then I mount it. Seems like there is a lot less pinch/pulsing that way. Also the "strum" technique seems to work for alot of people too - either on the inside like SXMXDrifter or just take a flat head screwdriver or your tweezers to the top of the coil and scrape it across the top of the coil. I'm not sure what it actually does, but it seems to make it require much less pinch and pulse (I use top of the coil method).

 

[Bunnykiller]

most wire we use as coil material is conductive before it is heated to a point of glowing... if you make a coil and dont "glow" it the wire that is in contact with the next wrap is capable of conducting current, therefore allowing for a shorter circuit to occur. Once the coil is heated to the "glow" point, the wire oxidizes and creates an "insulative" coating on it thus insulating it from each wrap. It may take a few sessions of "glowing" the coil to create the oxidation required to insulate...

what I have noticed, is when I make a new coil and check for ohms, it is usually lower before I "glow" it, once it has been "glowed" the ohms fall into the expected range...