Coils

[johnboy]

Good day all,
If I wind more coils onto silica wick do it increase or decrease the Oms, Thanks.

[Deleted]

More coils (of the same diameter), with the same type of wire, increases resistance (ohms).

The wire we use is known as resistance wire. It has a set amount of resistance (ohms ) for a given length. So the longer the piece of wire the higher the resistance ( more ohms ) as long as the coils are not touching.

Summary if you want to increase the resistance you need a longer piece of wire. You can increase the number of coils, or you could increase the diameter of each coil (don't forget the silica will need to be touching the coils so you need thicker silica or double up the silica if you increase the diameter of the coils)

[babs]

allaboute-cigarettes.proboards.com/thread/32391/microcoil-cotton-guide?page=1&scrollTo=575580 sorry don't make coils yet myself but this has a chart on wraps and oms it might help

[johnboy]

Cornersruns ------Babs , That was quick thanks,

[giles]

Just one thing to add - if you make dual coils, then the resistance goes down - two identical coils wired in parallel (the normal way) have half the resistance of one of them by itself. Which is why dual coil attys like the iclears use a lot of juice.

[2risky]

Here is some science, for which I apologize in advance.

Resistance in a wire is proportional to its length and inversely proportional to the cross sectional area of the wire. It also depends on the material the wire is made from.

Assuming the same material, to increase resistance you would need to make the wire longer and/or decrease its cross section (ie use a thinner wire).

Specifically
R = (r x L)/A
where R is resistance,
L is length,
A is cross-sectional area
r is known as the resistivity of the material, often denoted by the greek letter rho, but not in this case due to the difficulty of finding it on a qwerty keyboard.

So extra coils = higher resistance.