Rebuilding

[superhours]

Does anyone have any tips for rebuilding? I'm currently building a dual coil on the fogger v4.1 and I can't seem to get it to around the 1 or subs. My coils aren't as tight as everyone else I see either. What are the basics of building coils? I can't seem to find any video that shows/explains how building these coils work. I am grateful for any tips.

 

[State O' Flux]

Without any specific information about your wire and build... help will be difficult. For example, how are you measuring resistance?

An example build would be as follows: 28 gauge - 10/9 wrap on 2mm mandrel - 2mm legs = 1.4Ω per coil... or 0.7Ω if installed as dual coils in parallel.
If the legs are longer... say 3.5mm, then to get the same resistance, it would end up being a 9/8 wrap.
The length of wire - at 78.2mm contact to contact - doesn't change... but more leg means fewer coils.

Click on both my sig line hyperlinks... there's information there that will help you tremendously.

Cheers

 

[superhours]

Without any specific information about your wire and build... help will be difficult. For example, how are you measuring resistance?

An example build would be as follows: 28 gauge - 10/9 wrap on 2mm mandrel - 2mm legs = 1.4Ω per coil... or 0.7Ω if installed as dual coils in parallel.
If the legs are longer... say 3.5mm, then to get the same resistance, it would end up being a 9/8 wrap.
The length of wire - at 78.2mm contact to contact - doesn't change... but more leg means fewer coils.

Click on both my sig line hyperlinks... there's information there that will help you tremendously.

Cheers

I'm actually quite new to RBA and not too knowledgeable about this topic. I'm trying to achieve a 0.7ohm resistance with dual coils since the fogger only allows for dual coils. I'm thinking of using 24G kanthals for this..would that be a good idea? I believe mech mods are in "series" circuit therefore the resistance should add up which is why I think I should be using 24G Kanthal, but I could be wrong. Please input on this.
I was using a screwdriver..to wrap the coils but I'm not exactly sure what the size is. It just looked small enough to fit the building deck.
I don't exactly understand what you mean by legs. Could you please elaborate?

 

[iamthevoice]

The legs would be the straight bits sticking out of the coil on each side.

 

[State O' Flux]

I'm actually quite new to RBA and not too knowledgeable about this topic.
That's OK... which is why I suggest reading the information in the links - so you can learn.
I'm trying to achieve a 0.7ohm resistance with dual coils since the fogger only allows for dual coils.
I'm thinking of using 24G kanthals for this..would that be a good idea?
Not really. 24 gauge is better for deep sub-ohm. Using 24 gauge to obtain 0.7Ω would be two 21 wrap, 1.4Ω coils in parallel. The example I gave you in my first post is the best choice for the resistance you want in a dual parallel build.
I believe mech mods are in "series" circuit therefore the resistance should add up which is why I think I should be using 24G Kanthal, but I could be wrong. Please input on this.
You are misinformed. A mod is a power supply device. If we're talking a single battery tube mod - the mod has nothing to do with how you build an atty... other than matching resistance to battery maximum continuous current output - which are Ohm's law formula variables.
There are dual battery box mods that can be series or parallel... but that's a separate issue, and still has little to do with how you build an atty other than what I just said.
I was using a screwdriver..to wrap the coils but I'm not exactly sure what the size is. It just looked small enough to fit the building deck.
I don't exactly understand what you mean by legs. Could you please elaborate?
Legs are the unwrapped part of a coil on either end that go to the terminals... they are included in the determination of resistance, because the coil itself doesn't matter - only the length and thickness of wire determines resistance - the coil dimensions in between have no bearing on resistance.

There's a lot you don't know... and a lot you need to learn. You'll need to ask one question at a time... because I think you might be getting several things confused. Read the links I offered. ;-)

 

[UncleChuck]

Late to the party/please delete

 

[Maurice Pudlo]

Dual coils in series: (+)—////–////—(-)
Dual coils parallel: (-)—////—(+)—////—(-)

Use the calculator, place on an ohm reader in a fully assembled state to check ohms prior to firing, correct any build errors that don't come reasonably close to calculated expectations prior to firing. Use the calculator to check if your battery is capable of firing the coil you built with a margins of safety remain (20% is very reasonable, 1% is not). Do not use a build that does not return a stable reading on the ohms reader.

Read a metric boatload on this forum, the advice and help is simply amazing.

Maurice

 

[superhours]

There's a lot you don't know... and a lot you need to learn. You'll need to ask one question at a time... because I think you might be getting several things confused. Read the links I offered. ;-)

Okay okay so I'm kind of playing around with the coil wrapping calculator and I think I kind of figured a little bit out.
The length and thickness of the wires affect the resistance. Thicker and longer = more resistance. Thinner/shorter = less resistance.
I'm still not sure how to do the math to get .7 ohms from two 1.4 ohm wires.
I'm thinking the equation is R=1(1/x + 1/x) (remembered it from Physics, so long ago lol)
Also seem like the bigger the diameter, the less the coils but would it be same to assume that the length of the wire when stretched out is still the same?
I also have questions on techniques on how to properly wrap the wire. Anything I should know?

 

[Susan~S]

Also seem like the bigger the diameter, the less the coils but would it be same to assume that the length of the wire when stretched out is still the same?

Not sure what you are asking. Could you clarify?

I also have questions on techniques on how to properly wrap the wire. Anything I should know?

Check out this blog post from Baditude. There are many links including video links on wrapping coils towards the bottom of the post: Information Resources for Your First RBA

 

[UncleChuck]

Almost there:

Thicker wire = Less Resistance
Shorter wire = Less Resistance

Thinner wire = more resistance
Longer wire = more resistance

The math for a dual coil is pretty easy assuming the resistance of the two coils match. Just take whatever TOTAL resistance level you want to achieve, and double it, that's the required resistance of EACH coil. In your case you said you want a total resistance of .7, so if you double .7 you get 1.4 ohm, the required resistance of each coil.

 

[Maurice Pudlo]

Dual coils in series: (+)—////–////—(-)
Dual coils parallel: (-)—////—(+)—////—(-)

Use the calculator, place on an ohm reader in a fully assembled state to check ohms prior to firing, correct any build errors that don't come reasonably close to calculated expectations prior to firing. Use the calculator to check if your battery is capable of firing the coil you built with a margins of safety remain (20% is very reasonable, 1% is not). Do not use a build that does not return a stable reading on the ohms reader.

Read a metric boatload on this forum, the advice and help is simply amazing.

Maurice

On the Fogger parallel dual coils look like this:
////|
(-) (+)
|////



You can cut and paste this link into your browser for another video.
https://www.youtube.com/watch?v=e6SMJD8AcM4

Maurice

 

[superhours]

Thanks for all your help! I'm ordering wires right now. I'll update when I get them and using this new knowledge, do a build and see how it goes.

 

[superhours]

Just reporting in here, I got the coils to work! 2mm diameter at 7/8 wraps for .57 or so, fluctuation of course. Don't know what's up with the tank though. It keeps leaking and gurgling. Others don't seem to have this problem. Maybe mine is just defective.

 

[Hoopie]

If your ohm reading is fluctuating on the same meter, check your deck screws and if your coils are clear of touching the deck/posts/etc.

I can't say why it's leaking and gurgling but it most likely is your wicking. You could watch this video and see if it helps.
https://www.youtube.com/watch?v=gk_Zre35Eho

 

[TornadoAlley]

Just reporting in here, I got the coils to work! 2mm diameter at 7/8 wraps for .57 or so, fluctuation of course. Don't know what's up with the tank though. It keeps leaking and gurgling. Others don't seem to have this problem. Maybe mine is just defective.

You most likely have it wicked improperly. Let me dig up the vid of how I wick it. Also, make sure you have a tiny o-ring on the top piece of the chimney.
Edit; The video above is how I wick mine, also read up on battery safety so you don't hurt anyone including yourself!!