What could be causing dry hits?

[Glytch]

So I've been using a rebuildable ECR head for my Melo III for about 3 weeks now. I've been through many different variations of wire, ID, spacing, wicking etc and I thought I'd found the right way to wick this thing but alas today I'm getting sorta dry hits again.

When I say sorta dry hits I mean that when I chain vape the third pull or so starts tasting kinda dry. It's not a complete dry hit but I can taste it's starting. There are air bubbles during draws though.

I started using Kanthal A1 28g but changed to SS316L 26g. I'm doing 6 or 7 wraps, 3mm ID, spaced coils which ohm out at around 0.4 to 0.5 ohms. I'm wicking using some standard organic cotton purchased from SAVapeGear. The coils glow evenly from the inside out and I'm fluffing the cotton out on the outside of the wicking holes.

I started off leaving too little cotton on the outside of the wicking holes and eventually figured out that I need to leave more on the outside. I've even kept the two outer layers of cotton aside for my next wicking to measure less or more depending on the previous wicking. I've even tried pushing some cotton down into the inside of the coil.

This week I got it spot on and thought I'd found the perfect amount of wicking material. Cut the exact same amount based on the outer pieces I'd kept aside. But the sorta dry hits persist.

Vaping at around 27.5w and doing direct lung for about 3 - 4 seconds each. If I draw for longer the hit starts becoming dry.

My question is really what causes dry hits? Cotton to tight in the coil? Too much cotton on the outside of the wicking holes? Too little cotton on the outside? Not enough surface area on the coil? Too much surface area on the coil? Do I need to rebuild the coil every time, or can I just rewick?

For those with experience with rebuildable heads how often do you rebuild? How often do you rewick the same coil?

Any advice would be appreciated.

 

[Glytch]

I also sometimes get a sizzle from the coil for about 0.5 to 1 second after I release the fire button.

 

[Glytch]

Ok. Scoured the forums for other posts and @Andre is the man with all the experience. He recommends in a thread (that I can't be bothered to link to right now) that the ECR doesn't handle sub-ohm particularly well. Someone else also recommended stuffing the cotton into the wicking holes and leaving only a little on the outside.

Did 7 wraps with 28g Kanthal at 2.5mm spaced coils and ohmed out at 1.52. Stuffed the cotton all the way in and it's wicking perfectly.

I would like sub-ohm vapour production and flavour so I'll try 26g SS and see how close I can get with it still wicking properly. Going to try 3.0mm spaced.

@Andre do you think spaced coils help with the wicking? Have you managed to get anything lower than 1ohm working consistently? If so what wire did you use?

Thanks

 

[Sarx]

Would also love to know how different types of cotton compare in terms of wicking speed....

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[Andre]

I remember you said you like to go sub-ohm for faster ramp up time. I have never gone below 0.8 Ohms on the ECR. Usually around 1.0 Ohms, vaping at max 25 W, mostly around 20 W. Typically using 27 g Kanthal, contact coil on a 2.5 mm mandrel. Have not tried spaced. Have not had a dry hit.

What I did have is some juice in that groove above the hidden air slots, which I hated. For my last wicking I added 2 very thin, rolled pieces of cotton to either side of the coil. Pressed them in there like in a U-form against the sides of the ECR, making sure they do no go directly underneath the coil or on either side of the coil to impair the air flow. The tails of those thin pieces I put into the wick grooves and cut them with the wick proper. Now on about my 10th tank (2 ml Melo tank) and that groove has not seen any moisture. Maybe this can help with your problem.

 

[Glytch]

I remember you said you like to go sub-ohm for faster ramp up time. I have never gone below 0.8 Ohms on the ECR. Usually around 1.0 Ohms, vaping at max 25 W, mostly around 20 W. Typically using 27 g Kanthal, contact coil on a 2.5 mm mandrel. Have not tried spaced. Have not had a dry hit.

What I did have is some juice in that groove above the hidden air slots, which I hated. For my last wicking I added 2 very thin, rolled pieces of cotton to either side of the coil. Pressed them in there like in a U-form against the sides of the ECR, making sure they do no go directly underneath the coil or on either side of the coil to impair the air flow. The tails of those thin pieces I put into the wick grooves and cut them with the wick proper. Now on about my 10th tank (2 ml Melo tank) and that groove has not seen any moisture. Maybe this can help with your problem.

Hidden air slots?

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[Clouder]

@Glytch another thing to consider, which I had on my subtank sometimes, When you chain vape, you have to keep in mind that your wick has to have enough time to soak up juice, I noticed that, I vape the cotton dry when taking loooooong drags and then BOOM! A dry hit from hell!

 

[Andre]

Hidden air slots?

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Jip, the air slots are hidden behind the part at the bottom, which you turn for more of less air.

 

[Glytch]

Jip, the air slots are hidden behind the part at the bottom, which you turn for more of less air.

Right. Got it. Also had that slight leaking. I'll give it a try. Thanks.

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[Glytch]

Ok. So I think I finally nailed this thing.

I tried 28g kanthal five spaced wraps which ohm'd out at 1.2 and no dry hits but sacrificed vapour production and flavour. I've been vaping that for about a week. Played around with wicking and learnt a thing or two.

Today I did 11 wraps of SS316L 26 gauge (no spaces) and wicked it slightly differently. I used the same amount of cotton and fluffed it out as per usual. What I didn't do was push the excess cotton on the outside into the wicking holes like I usually do. Instead I juiced it and flattened it out around the outside of the ECR head so it was nice and flat on the outside.

Vaping happily at 0.75 ohms with no leaking, no dry hits, a decent amount of vapour and good flavour.

I've also found that you need to make sure that the lead that goes through the centre of the rubber grommet is not touching the inside wall of the coil housing. If this happens I get a weird hissing noise when I fire the coil. I bend the inside lead inwards to make sure it isn't touching. This seems to yield better performance (probably because the coil isn't shorting ).

Hope this helps someone reading this thread.

 

[notna]

This thread seems glytchy, probably due to the absence of pix..

Maybe I'm just tired today but I have difficulty conceptualizing the lead that goes through the centre of the rubber grommet somehow touching the inside wall of the coil housing...

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[Glytch]

This thread seems glytchy, probably due to the absence of pix..

Maybe I'm just tired today but I have difficulty conceptualizing the lead that goes through the centre of the rubber grommet somehow touching the inside wall of the coil housing...

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Are you trolling or are you genuinely interested?

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[notna]

Are you trolling or are you genuinely interested?

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Both. Had a bit of a giggle at the pun I made, but also interested to see exactly what you've done.

I have 2 of those ECRs I haven't used yet but am going to have to as soon as I run out of commercial coils for my Melo, so your trials represent valuable info.

 

[Glytch]

Both. Had a bit of a giggle at the pun I made, but also interested to see exactly what you've done.

I have 2 of those ECRs I haven't used yet but am going to have to as soon as I run out of commercial coils for my Melo, so your trials represent valuable info.

Right. I will post pics next time I build.

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[Mark121m]

Dry can be caused in my experiance by wicking to thick and or too much.

I have no experiance with a melo iii

But most tanks hate over wicking.
I still get it wrong in my goblin mini at times

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