Why do my claptons lose 0.2 ohms when adding half a wrap?

[sida]

I use 0.8 fused claptons in my MTL tanks. I have some prebuilt coils from 3 different brands, all rated 0.8 ohms.

The coils all come with the legs facing the same way but my tanks require them to be opposite so I always add an additional half a wrap. When I've finished the build the reading is always roughly 0.6 ohms. This happens regardless of the tank, mod, or which of the 3 coil brands I use.

I've never tried the coils unmodified as I don't have tanks that take both legs in the same direction. I assume the result of 0.6 is because I'm adding half a wrap but shouldn't more wraps increase the resistance? Why do I always end up with 0.6?

 

[Crispycritters]

It could be that adding half a wrap compresses the coil between the posts because of the extra width and causes a 'hot spot' where the current takes a short cut and doesn't go through a wrap or two - this will lower the resistance the mod can read..

it could be the coils aren't really 0.8 ohms even though they are labelled as such - generally the real resistance when fitted, glowed, strummed and bedded in will vary somewhat from their rated resistance - although normally not as much a variation as you are currently getting..

if adding half a wrap makes the coil compress between the posts, try removing half a wrap.

 

[sida]

It could be that adding half a wrap compresses the coil between the posts because of the extra width and causes a 'hot spot' where the current takes a short cut and doesn't go through a wrap or two - this will lower the resistance the mod can read..

it could be the coils aren't really 0.8 ohms even though they are labelled as such - generally the real resistance when fitted, glowed, strummed and bedded in will vary somewhat from their rated resistance - although normally not as much a variation as you are currently getting..

if adding half a wrap makes the coil compress between the posts, try removing half a wrap.

I've tried with coiloligy, vandy vapes and fallout coils. What really throws me is the fact that I get the same result regardless of the coil brand or mod or tank, even in my boro tanks I get the same result as my tanks with bigger decks. I do tend to squeeze the coils a bit when dry firing, I wonder if I'm causing a short cut there? Though it's still odd to me to have it happen every single time. I'll try removing half a wrap on the next build and maybe try without any squeezing to see what happens, thanks.

 

[LordOdin]

I use 0.8 fused claptons in my MTL tanks. I have some prebuilt coils from 3 different brands, all rated 0.8 ohms.

The coils all come with the legs facing the same way but my tanks require them to be opposite so I always add an additional half a wrap. When I've finished the build the reading is always roughly 0.6 ohms. This happens regardless of the tank, mod, or which of the 3 coil brands I use.

I've never tried the coils unmodified as I don't have tanks that take both legs in the same direction. I assume the result of 0.6 is because I'm adding half a wrap but shouldn't more wraps increase the resistance? Why do I always end up with 0.6?

I generally have to do the same, i did a build yesterday with a 1.0 ohm Clapton, after i had added the half wrap it came out at 1.02 ohms so the opposite of what happened to yours, i have had to take wraps off and they usually go roughly the same but in the opposite direction.

 

[zouzounaki]

space the coils and you’ll not have any problems

 

[Simon G]

I use 0.8 fused claptons in my MTL tanks. I have some prebuilt coils from 3 different brands, all rated 0.8 ohms.

The coils all come with the legs facing the same way but my tanks require them to be opposite so I always add an additional half a wrap. When I've finished the build the reading is always roughly 0.6 ohms. This happens regardless of the tank, mod, or which of the 3 coil brands I use.

I've never tried the coils unmodified as I don't have tanks that take both legs in the same direction. I assume the result of 0.6 is because I'm adding half a wrap but shouldn't more wraps increase the resistance? Why do I always end up with 0.6?

"I've never tried the coils unmodified"

They might be 'rated 0.8ohms' but obviously they are actually 0.6ohms....

what's that philosophy principle .... occam's razor?

Adding half a wrap isn't going to add much resistance and it certainly isn't going to take it away.

 

[Simon G]

.... either that or they are 0.8ohm coils and your mod reads them as something else.

either way, who cares? It's fine.

 

[LemmysCodPiece]

The more mass you add to a conductor the less the resistance will be.

 

[wraith]

Could it just be that the 0.8 is before you cut the length down by fitting it?

The effective resistive length is between the post clamps/screws.

If you lose 20% length that would take it from 0.8 to 0.6.

 

[zouzounaki]

The more mass you add to a conductor the less the resistance will be.

that’s not right. resistance decreases as cross sectional area increases, not mass.