Subtasks mini rba help.

[Zeusvapes]

Been having supply shortages locally on.. 5 ohm coils.

Local shop recommend. 5x1mm flat kanthal a1. I was looking for 28guage but the didn't have it.

My first attempt came in at 2 ohms.

Second at 1.2.

Both wraps were 5 coils. The first a larger diameter than the second.

Wraps are consistently firing and heating from the inside to outside of the tube.

2 questions.

1) how can I get lower ohms? I only want close to..5 nothing lower

2) with the current 1.2 build I find the airflow lacking considerably. This is on the wide open setting. Should I be using less cotton?

Thanks all.

I'm keep the wattage low and my voltage down near 3.5 as I start this new rba experience.

 

[Retro138]

I use 26 guage kanthal a1, 5 wrap on a 2.5 mm rod and get 0.5 ohms. Cut the wick it so it's just long enough to touch the rba deck, rabbit ear it and gently fluff it down into the chamber. Prime it and test fire, put everything together,fill tank with max VG juice and it hits like a champ.

Spaced coil btw, and it did take some time for me to get this down pat. I'm talking a half day of making coils.You'll get it.

 

[edyle]

Been having supply shortages locally on.. 5 ohm coils.

Local shop recommend. 5x1mm flat kanthal a1. I was looking for 28guage but the didn't have it.

My first attempt came in at 2 ohms.

Second at 1.2.

Both wraps were 5 coils. The first a larger diameter than the second.

Wraps are consistently firing and heating from the inside to outside of the tube.

2 questions.

1) how can I get lower ohms? I only want close to..5 nothing lower

2) with the current 1.2 build I find the airflow lacking considerably. This is on the wide open setting. Should I be using less cotton?

Thanks all.

I'm keep the wattage low and my voltage down near 3.5 as I start this new rba experience.

1: getting lower ohms is easy.
use less wraps or use thicker wire.
But is that what you actually want.

Use steam engine coil calculator

2: is the cotton blocking the airflow?

 

[Zeusvapes]

Thicker wire..... Can I twist 2 lengths of the flat together to form a single thicker strand?

" is that what you want?".... I believe so. With the lower ohms, max vg max airflow and low nic%... Running about 3.7 volts I blow huge clouds all day repeatedly.

Even with the stock 1.5 occ coils the vapor wasnnt on par with the. 5

 

[Zeusvapes]

Just checked the Calc. Thank you!

 

[edyle]

Just checked the Calc. Thank you!

over on the right there is a wattage box; that's important.
look for when the flame icon is green. blue is cold and red is hot. green is good

 

[Spencer87]

Ima move this o'er to New Members for you, Much more traffic there, and simple solutions is for the vapers just looking to get started with Vaping.

 

[Zeusvapes]

Regarding the little flame. Every combo I come up with. Using a target of.. 5 gives me a red flame at 10watts..

For example. Kanthal a1 flat ribbon. 5x1 target. 5ohms.

Even 28guage kanthal is red at 10 watts. 5 ohms.

 

[Stratsworth]

Regarding the little flame. Every combo I come up with. Using a target of.. 5 gives me a red flame at 10watts..

For example. Kanthal a1 flat ribbon. 5x1 target. 5ohms.

Even 28guage kanthal is red at 10 watts. 5 ohms.

The number of wraps is too low for a single strand of .5 x .1 ribbon or 28G to reach .5Ω, no matter what the inner diameter may be (2-3mm). One or two wraps - no bueno. To reach .5Ω safely you'll need a thicker gauge of wire.

I've had a number of builds on the Mini RBA+ and my favorite is a spaced 5 wrap 26G 2.4mm ID that comes out on the high end of .6Ω. You definitely want to aim for 5+ wraps like you've been doing.

The limited airflow could be a large ID build that's too low to the deck, but that's conjecture since I've never experienced it in any of my RBAs. Check it against another coil and see if the problem persists. If it was merely too much cotton stuffed in the coil you'd be getting dry hits.

 

[Zeusvapes]

Rebuild. Achieved 1ohm on 4 wraps.

Next at 3 wraps and a diameter of 5/16ths.. Hits 8ohm 3volts at 10 watts.

Getting there.


3 wraps if looking top down. 5 if your looking bottom up. ( the tails)

 

[Zeusvapes]

Airflow issue was too much extra cotton coming off the deck and up over the coil obstructing airflow and causing more liquid to be sacked into the chamber..

Can I double up the ribbon to a get a higher gauge?

 

[thailand]

Maybe a "parallel build"...or whatever its called. Hopefully the other members know the correct term.
Essentially, 2 strands of wire, side by side, and build 4-5 wraps with that. It should, in theory, halve the ohms, since you are using 2 coils. So, if you're at 1 ohm, this should yield 0.5 ohms with the same diameter and wraps.
Again, hopefully another member can mention the correct terminology.

 

[BShady]

I would suggest trying "stacking" the wire two pieces thick. If you cut 2 pieces of wire and lay them one on top of the other (so, instead of ----- being your wire, it looks like ======) and then wrap your coil you should be able to resolve most of these issues. Stacking .5x.1mm Kanthal A1 into two layers and wrapping it 4 turns around a 2.5mm mandrel without leaving space between the turns (what some call a "micro" coil) should give you a resistance of just above .5 ohms and will allow you a much greater range of adjustment for your power output without overheating the coil.

 

[Zeusvapes]

Shop let me trade the flat in for some kanthal round 28guage. Using 4 spaced wraps and a 2mm diameter I was able to hit.. 7.... I'm okay with it for now and it allows me a more variable range on my wattage than the flat did...

Previously my range was 8-12 watts hiring between 2-3.7 volts.

Now I can 8-24ish watts with a range of 2-4 volts without burnt hits.

Is there a preferred wattage for 80vg/20pg juice?

 

[edyle]

i'm using 28 gauge 10 wraps on 3.5mm diameter 2.6 ohms and usually vape it at 4.3 to 4.5 volts;;;; (might be mean instead of rms)

 

[Zeusvapes]

i'm using 28 gauge 10 wraps on 3.5mm diameter 2.6 ohms and usually vape it at 4.3 to 4.5 volts;;;; (might be mean instead of rms)

Is this producing heavy flavor and vapor? Or one or the other?

 

[Zeusvapes]

Alright I. Just wanted to update. In browsing through the dedicated sub tank mini builds thread I found some gold. Someone commented on the method to twist strands of kanthal was a drill and pair of pliers....... Boom!!!!!!!!!

Spun 2 strands of 28. Wrapped 4 times and hit. 4 ohms. With3mm diameter. Perfect!...

Could runs great. Making the next a 5 wrap and hoping for. 6 ohm build.@ 3mm Dia.


Thanks for all the help!!!!

 

[edyle]

Is this producing heavy flavor and vapor? Or one or the other?

i think what i like about it is it's harder to end up with a dry wick burnt taste all of a sudden.
it vapes best when i'm chain vaping

my 1.2 ohm 28 gauge give a more immediate puff, but if the wick gets too dry it gets some burn and will be burnt till i change wick.

 

[vincom]

if on the 1st version of the mini rba, dremmel out the juice channels, it will hit harder, be able to handle higher watts and less to no burnt/dryish hits