Kanger coil DIY issue

[CallmeB]

I'm having the most annoying problem. I use the coil wrap calc to calculate my warps but when I measure them my ohm meter readings are all over the place. I just wrapped a 5 turn coil 1/16th inch diameter with 32 gauge A1 kanthal and get a reading of 3.5 ohms!? ...? I'm not sure I trust my meter. It's a $10 multi tester, and it does fine for normal things like measuring continuity and voltages, but I think it is just not accurate enough to read this. What do you guys think? The calc said I'd have had to have wrapped 11 turns to get 3.5 ohms. I expect some variance, but a 2x more resistance is a bit much.

 

[umanbean]

Your multimeter leads (wires & probes) have a resistance of their own.

Touch the two probes together, note the resistance, then subtract that from your measurement of the coil. That should get you a lot closer.

Some (more expensive) meters have the ability to be "zeroed" while touching the leads together. The digital ones that zero out have a button, the analog ones have a little potentiometer (dial) so you can dial the needle to zero.

HTH

 

[3mg Meniere]

I bought two, and couldn't figure out how they work. You might be better off with one of these Ohm Meter by HCIGAR - ecigExpress , or an APV like Vamo.

 

[BigCatDaddy]

I'm having the most annoying problem. I use the coil wrap calc to calculate my warps but when I measure them my ohm meter readings are all over the place. I just wrapped a 5 turn coil 1/16th inch diameter with 32 gauge A1 kanthal and get a reading of 3.5 ohms!? ...? I'm not sure I trust my meter. It's a $10 multi tester, and it does fine for normal things like measuring continuity and voltages, but I think it is just not accurate enough to read this. What do you guys think? The calc said I'd have had to have wrapped 11 turns to get 3.5 ohms. I expect some variance, but a 2x more resistance is a bit much.

That build should get you a 1.6Ω or so coil. I would suggest just getting an ohm meter so you know for sure. If you do get one, just know that a lot of them will give you a number when you turn them on. Mine sez 1. I have to subtract that from the display to get the correct Ω's. So, if I get a 1.7 on the meter, it's really a 1.6Ω build.

 

[DavidOck]

The low end DMMs usually have low end test leads, with very small wire inside. And the chromed tips may be another high resistance spot. You can dress them down with an emery board, rolling the tip across like you're sharpening a pencil. Zeroing the reading, as mentioned, is very important. Just like Kanthal, the smaller the wire diameter, the higher the resistance. I have one that's 0.4 Ω...

That said, how are you measuring? After full assembly? Or before putting it back in the base? Are you holding the test leads firmly on it? Variations in pressure can change the reading.

Is your assembly correct? I inadvertently ran the positive lead through the hole on the positive pin once, and got randomly changing readings... and haven't forgotten that yet

 

[Unforeseen]

Moved to Assorted APV Discussions - Clearomizers

 

[CallmeB]

Alright I should have specified that I am not new to using a multimeter. I just don't use one on a daily basis so I can't justify spending 100's on a Fluke. I just think my multimeter is crap. Might be the connectors. I am measuring after assembly. I'll eventually get one of those ohm meters just for measuring e cig coils, but for the time being I think I will just stick to guessing. Worst that can happen is I end up having to use more voltage. I'll know immediately if the ohms are too low. I'm using an evod varriable voltage battery so it won't even fire below a certain ohm and if I get massive hot coils at 3.3 I'll know it's too low. Thanks for the help.

 

[DavidOck]

Actually, the worst that can happen is that the battery goes into thermal run-away in your hand. And you get to be the media's current "argument" about how unsafe e-cigs are. Yes, your Evod battery is sold as having short protection, as are most regulated mods, but it's not something I'd want to use as my FIRST line of defense.

I can certainly understand not wanting to shell out big bucks for a Fluke, and yes, it's possible your current low end DMM is flakey. But when, on the lowest Ω setting, when you short the leads the reading should stabilize at some value. Solid and steady pressure between the tips is important. If it doesnt', yes, maybe a bad meter, leads, or connections. Or possibly even just a low battery inside the meter.

 

[twgbonehead]

Why not shell out $35-40 for an MVP, or ~28 for a VV V3? Both are more accurate than my $5 HF meter.....