Formula for calculating ohms when recoiling dual coil heads

[toots]

Mar 28, 2014 15:53:19 GMT erik514 said:

Mar 28, 2014 13:24:42 GMT toots said:

Hehe, just found out the formula for calculating the ohms when recoiling dual coil heads, and it is easy peasy to work out

Ok, all you do is this:

Example: Using 2 x 2.50 ohm coils

Formula: 2.50 + 2.50 = 5 divided by 4 = 1.25 ohms

How easy is that. I had no idea how to work it out but now I do, and hopefully this will help anyone else out like me starting to rebuild their dual coils

I've got ready made ones coming from FT so I thought I'd better find out how to actually work it all out for myself, instead of relying on other people to tell me which ones to get. I also know a few of us on here have just started to buy these ready-made coils and some of us will be re-coiling dual coil heads.

It's the right answer but just divide the resistance of the coil by 2. Each coil is 2.5 so 2.5/2=1.25

Ok, but what if you need to use 2 different resistances then???? For example a 2.5 and a 2.0 - what is the result then, and what is the method/formula?

[toots]

Mar 28, 2014 21:54:40 GMT stonethecrows said:

toots, I've got a load of them coming from ft, too. I can't be doing with all that twinding/bending/twisting all the time. Might as well some other bugger do it for me:).

Yeah, me neither, I'm all for simplicity. Watched some youtube videos on making up them coils, some made it look fairly easy but some made it look pretty difficult. Nah, all that faffing about, forget it, much easier when you can just buy them ready-made.

Went out and bought myself 2 pairs of the smallest pliers I could find today, just so I can pull them heads apart easily, nice little diddy ones, just right for my hands (only got childsize hands lol). Hubby said I could use his pliers, but the flippin size of them though was ridiculous for my size hands.

[stonethecrows]

These are nice and cheap and good quality, toots. Good for tweaking things. Careful though, they are bloody sharp with their pointy ends! www.fasttech.com/product/1195700

[toots]

Mar 28, 2014 22:24:06 GMT stonethecrows said:

These are nice and cheap and good quality, toots. Good for tweaking things. Careful though, they are bloody sharp with their pointy ends! www.fasttech.com/product/1195700

I saw some of those when I was looking for my pliers in the shop. Wondered what the hell they were, now I can see they are in fact tweezers weird looking things. I've got some normal tweezers, hopefully they will suffice as those at FT look a bit lethal.

[stonethecrows]

Thought I best get some of my own, because, the wife went ape chit when I mislaid hers, for her. Never realised a pair of tweezers could mean so much to her .

[dave]

Just keep it simple toots and use coils of the same resistance - dual coil atties work best that way

You will find though that you will need to use a bit more voltage with dual coils at 1.25 ohms, say, than you would with a single coil of the same resistance.

[toots]

Mar 28, 2014 23:12:50 GMT dave said:

Just keep it simple toots and use coils of the same resistance - dual coil atties work best that way

You will find though that you will need to use a bit more voltage with dual coils at 1.25 ohms, say, than you would with a single coil of the same resistance.

I always have mine set on the wattage on my vtr so would I need to up that you reckon.

Actually, I only normally use the iclear 30s's on the vtr and they are dual coils at 2.0 ohms so if I put my new aerotank or protank 3 on the vtr once I've recoiled them at 1.25 ohms would I need to up the wattage?

[Adam78]

Mar 28, 2014 22:09:52 GMT toots said:

what if you need to use 2 different resistances then???? For example a 2.5 and a 2.0 - what is the result then, and what is the method/formula?

yinyang already posted it.

Mar 28, 2014 14:07:06 GMT @yinyang said:

Rt = (R1 x R2) / (R1 + R2)

To put it another way.

Take the resistance of Coil 1 and multiply it by the resistance of Coil 2 and note down that number.

(2.5 x 2.0) = 5

Then you take the resistance of Coil 1 and add it to the resistance of Coil 2 and note down that number.

(2.5 + 2.0) = 4.5

Then you divide your first number by your second number to get the total resistance of your dual coil.

5 / 4.5 = 1.1ohm

Resistance of your dual coil would be 1.1ohm

[toots]

Thanks Adam78 - got it now