RM4 Coil Build Discussion/Suggestion

[built4feel]

So I've just been doing single coil horizontal builds with 28g kanthal between 1.3 - 1.6 ohms (2mm-2.4mm diameter) and wicking with rayon. I'm definitely happy with the results and the ease of use. I wanna try duals coils or a vertical build next. I haven't found too many people discussing what styles or kind of builds they like for this particular atty. I will post a pic with my phone in a minute of my current coil.. The airholes on the AFC are slightly high off the deck, so I've been trying to find the right position, but Im thinking that vertical coils would be easier and more efficient. Any ideas and input are appreciated. Its a sooper doopper awesome atty! (and my first BF/Reo). Lots of vapor production and great flavor! I prefer the largest airhole in single coil mode BTW.

Probably over did it with the rayon a bit on this one...I used more so that it has a smaller chance of over sponking or leaking threw the airhole... works great though! Flavor on my last build was better, and it was centered on the deck better with better wicking.

 

[RSZ1]

My RM4 is incoming along with my first Reo (YESSSS!!!! FIST PUMP!) so I don't have much to add right now. I've been using rayon as well, and it looks to me like you might have a bit too much in there. BUT, the rayon tends to shrink down a bit after a few mils are put through it. If it's wicking good and no funky flavour, then it's good!

I do have a vertical build in a 454 right now, and seems to work ok. It seems as though horizontal coils wick better for me, since you have two ends of the wick feeding the coil instead of one.

Looking forward to sharing ideas once the RM4 gets here.

 

[el Jexican]

My current coil in the RM4 is a twisted 26 guage microcoil. 5 wraps around a 5/64th. Its like .35ohms. A full on dense and flavorful vape.

 

[BockinBboy]

Awesome setup!

I haven't experimented quite enough with the single coils on this atty yet to offer suggestions better than your current thoughts. I too am using rayon and finding it is at least as good as KGD, and in some regard, I'm liking the rayon better - but we know that's a whole different thread, haha! (Pun intended =P ). I think you are right, a tiny bit heavy on the rayon this time around - but there is a learning curve when you are getting the hang of a new wicking material.

Currently I'm running dual micro coils with 28g kanthal, 8/7 wrap, centered, ~1.5mm off the deck, 1.0 ohms, ~3/4 of largest air holes open - phenomenal vape. Took my time with this build getting it right at 1.0 ohms and tweaking the wicking just right, while experimenting with the rayon. I'm hoping the coils last a long time, because I fear trying to recreate it, LOL!

- Bboy

 

[built4feel]

Awesome setup!

I haven't experimented quite enough with the single coils on this atty yet to offer suggestions better than your current thoughts. I too am using rayon and finding it is at least as good as KGD, and in some regard, I'm liking the rayon better - but we know that's a whole different thread, haha! (Pun intended =P ). I think you are right, a tiny bit heavy on the rayon this time around - but there is a learning curve when you are getting the hang of a new wicking material.

Currently I'm running dual micro coils with 28g kanthal, 8/7 wrap, centered, ~1.5mm off the deck, 1.0 ohms, ~3/4 of largest air holes open - phenomenal vape. Took my time with this build getting it right at 1.0 ohms and tweaking the wicking just right, while experimenting with the rayon. I'm hoping the coils last a long time, because I fear trying to recreate it, LOL!

- Bboy

I like your style!

Can you help me understand how you got 1.0ohm dual micro coils with 28g and only 8/7 wraps?? I'm sorry, from my understanding it seems like you're only talking about one of the single coils. With the 28g, 8 wraps around a 1.5mm comes out to a 1ohm single coil... If you're doing a dual coil to total resistance would be halfed, and with that it would be a 0.5ohm coil, which is what I was planning on trying eventually... I hope Im not confusing anyone else, but I am utterly baffled..

edit: What diameter are you using to wrap those??

 

[supertrunker]

I only run duals on the RM4, because for single coils i have loads of RM2s and they are hard to beat. I use silica wick.

For the RM4 i make 2 coils each of 26g kanthal wrapped 4 times around a 2mm screwdriver. 0.25Ω all done. I line them dead centre of the airholes and that gives me enough room under the coil to tuck a little bit of the silica before i trim the ends.

Wide open airholes. Great vape!

Hard on batteries!

T

 

[vengaman]

I broke one of the negative legs on my RM4, so it looks a little different, but it just means I dual coil the old school way.

I wrap either 28g or 30g (depending on my mood and jooz). always dual, 9-11 wraps, middle airholes (usually). koh-gen-do cotton, and I wick with a single piece of cotton that I take round in a horseshoe kinda shape. I find this makes a really nice centre well - the juice comes up directly on the coils, and soaks everything you want it to a treat. never leaks and great vape. c1.04 ohm

edit: I wrap coils for all drippers on a 14g needle

 

[SoftSell]

Note: tapatalk destroys my pictures, but I will try. Sorry for the quality.
I started with 28ga kanthal 5/6 wrap dual coil on a 2mm screwdriver with organic cotton, max airflow, right around .7ohm and it was great. Then the screws would sheer my kanthal over and over again, even after sanding them down.
So I switched my build, first time with a single coil, buuuut here it is:
28ga/24ga twisted single coil kanthal, 5/6 wrap around 2mm, organic cotton, .4ohm. Heats up perfectly after a few pulses and adjustments, it's too hot for my liking with only one air hole, so I use both large air holes which cools it off nicely. Very even glow from centre to the outside, very respectable vapor production, with quite a bit of taste.
This is the set up that has converted a few friends to Reo Believers.

Edit: picture apologies

 

[muzichead]

I like your style!

Can you help me understand how you got 1.0ohm dual micro coils with 28g and only 8/7 wraps?? I'm sorry, from my understanding it seems like you're only talking about one of the single coils. With the 28g, 8 wraps around a 1.5mm comes out to a 1ohm single coil... If you're doing a dual coil to total resistance would be halfed, and with that it would be a 0.5ohm coil, which is what I was planning on trying eventually... I hope Im not confusing anyone else, but I am utterly baffled..

edit: What diameter are you using to wrap those??

It would seem he is not running micro coils... To get the 1.0Ω resistance for duals he would have to have 5/32" ID coils. You are correct in that a dual micro, (1/16" ID), would be .5Ω on a 8/7 wrap....

 

[muzichead]

Note: tapatalk destroys my pictures, but I will try. Sorry for the quality.
I started with 28ga kanthal 5/6 wrap dual coil on a 2mm screwdriver with organic cotton, max airflow, right around .7ohm and it was great. Then the screws would sheer my kanthal over and over again, even after sanding them down.
So I switched my build, first time with a single coil, buuuut here it is:
28ga/24ga twisted single coil kanthal, 5/6 wrap around 2mm, organic cotton, .4ohm. Heats up perfectly after a few pulses and adjustments, it's too hot for my liking with only one air hole, so I use both large air holes which cools it off nicely. Very even glow from centre to the outside, very respectable vapor production, with quite a bit of taste.
This is the set up that has converted a few friends to Reo Believers.

You would have to do an awful lot of sanding to get the stainless screws flat on the bottom. It would be best to use a file to do it....

 

[built4feel]

Softsell, and to anyone who may still have the older style screws for their posts, Rob has corrected that issue and all RM4 comes with the updated allen head screws. They are also on the website for purchase. IMO they are the best post screws I've had on an RDA. The allen head wrench is kind of annoying but it works! I'd suggest you get some, because those old, bigger things look hazardous!

Thanks so much for the input guys! Gets me all pumped to try out a new build!

 

[SoftSell]

You would have to do an awful lot of sanding to get the stainless screws flat on the bottom. It would be best to use a file to do it....

Yes, you are correct. I did in fact use my files, with limited success. They are much flatter with dull ends, but shear the kanthal 8 out of 10 times. Now it does work occasionally, but the postholes are to small for my go-to dual coil build. This single coil ^^^^ has been on par with quite a few dual coil builds as far as flavour AND vapor production to my surprise. Hard to squeeze in the Rm4 though....
Edit: I ordered a second reo last night, with new rm4 screws.

 

[vengaman]

Softsell, and to anyone who may still have the older style screws for their posts, Rob has corrected that issue and all RM4 comes with the updated allen head screws. They are also on the website for purchase. IMO they are the best post screws I've had on an RDA. The allen head wrench is kind of annoying but it works! I'd suggest you get some, because those old, bigger things look hazardous!

Thanks so much for the input guys! Gets me all pumped to try out a new build!

yeah but shipping some screws to AUS will wait until my next order I got the RM4 real early on. quickly ground the screw heads to a reasonable size and easily softened the edges of the bottom of them on said grinding wheel.

with the exception of my Rose v2 atty, everything I have is Philips headed so I am happy with them after the slight modifications.
fully agree, those snugged up new allen screws do look much neater though....now you got my OCD twitching again !

 

[muzichead]

If you filed them flat and still are shearing off your wire, you are tightening your post screws way too tight...

 

[SoftSell]

If you filed them flat and still are shearing off your wire, you are tightening your post screws way too tight...

Right. I've built atomics prior to the rm4, along with a number of other rda/rba/rta coils. I've never had this issue before. If I don't tighten enough, the screws loosen quickly over a short period of time and/or not making a quality connection.
Back to the files I suppose....

 

[BockinBboy]

I like your style!

Can you help me understand how you got 1.0ohm dual micro coils with 28g and only 8/7 wraps?? I'm sorry, from my understanding it seems like you're only talking about one of the single coils. With the 28g, 8 wraps around a 1.5mm comes out to a 1ohm single coil... If you're doing a dual coil to total resistance would be halfed, and with that it would be a 0.5ohm coil, which is what I was planning on trying eventually... I hope Im not confusing anyone else, but I am utterly baffled..

edit: What diameter are you using to wrap those??

I'm sorry, yes you are right... It's exactly 1.0 ohm per coil. I just meant I spent time getting that right on so both coils are exactly 1.0 ohms *each* and firing as evenly as possible. Ohm reader reads out .50 for duals. It's a pretty warm vape with great flavor.

- Bboy

 

[SoftSell]

Keeping to the subject at hand, although it's hard to capture I good vapor picture, here is a 2 second pulse with my build

 

[built4feel]

Just an update; I'm liking the ~0.7ohm build I got in mine,- duals of 28g with a 2mm ID and 8 wraps. Probably the best flavor and vapor production I've gotten with it so far. Heats up fast and even.

Coils in line with airholes- 3/4 largest duals

 

[BockinBboy]

That's pretty close to the build I have going... I think I used a 16gauge needle to wrap it to get the .5 ohms, but my blunt needles are all in a small box and I'm certain the color coded caps have gotten switched around =\
My calipers tell me the needle is 1.62mm OD though

Your wick amount through the coil looks great for rayon from what I can tell.

Might try yours next with a 2mm for a slightly cooler vape, as I want to try a couple juices that would be better with a little less heat... But I'm really digging the heat for my current juice.

- Bboy