Problem with Subtank RBA

[doveman]

I'm having a weird problem with my Subtank RBA. One evening, after working normally all day, it started firing for only 0.3s and then cutting out. Even though I'd only changed the coil a few days before, I thought I'd fit a new one but that didn't help and it was reading as "shorted" or "low resistance" but the coil certainly wasn't making contact with anything it shouldn't.

Then I found even with no coil at all, it would fire briefly and a puff of vapour would come out of, or from somewhere near to, one of the screw holes in the posts (I'd removed the screws completely at this point)! I thought the post that has a bit of play to it might be shorted to the other, fixed, post by gunk where the gap between them should be, so I cleared that area with a thin blade until I could see a clear gap but that didn't help. Testing it again yesterday, still without a coil fitted, I noticed that it fires for 0.3s and reads 0.6-0.7ohm whilst producing a puff of vapour! If I fire it again straight away it doesn't always produce a puff but if I leave 5-10s between it seems to.

I've been using my Nautilus for a few days as I had a new atty for that lying around but it seems to have worn out/got gunked up already and doesn't taste great anymore. I then switched to using one of the used Subtank OCC coils I kept, which was OK for a few days but now the juice is leaking a lot, so I might have to resort to my old Spinner and mini Protank to keep me going but that's going to be a pain after using my Cloupor mini with larger/better tanks, so if I can fix my RBA somehow that would be nice. I've ordered a new mini RBA Plus from FT www.fasttech.com/products/0/10014112/2390700-authentic-kangertech-subtank-mini-rba-plus-coil and some OCC coils from Amazon but both could take a while to get here (obviously the OCC coils should get here first but I haven't received confirmation of dispatch yet).

[Greg]

If it's firing with no coil in then clearly you some kind of short or at least low resistance path. Based on what you've said I'd suggest you strip the RBA down to its component parts and clean them all thourougly and check none of your insulators have melted.

[DiscoDes]

I think you may have a short somewhere in your RBA base, as the Nautilus works fine (have you tried other atomisers?) it would not appear to be your device.

They are pretty cheap to replace, or put a wanted advert in the Classifieds section, there is a good chance that someone will sell you one if you wnt to get one quickly.

[doveman]

May 29, 2016 9:46:18 GMT Greg said:

If it's firing with no coil in then clearly you some kind of short or at least low resistance path. Based on what you've said I'd suggest you strip the RBA down to its component parts and clean them all thourougly and check none of your insulators have melted.

Thank. I didn't realise the RBA could be stripped down but after reading your post I looked into it and found the bottom post with the holes in it unscrews, so I stripped it down and gave everything a quick wash.

It's sort of working now. Without the coil it showed "Check atomiser" as expected and with the coil it fires now but cuts out after 2-3s. I've got two Cloupor minis and have set both to 4v/20w. When I fire it, the readout shows 0.51ohm and 3.20v. On my older, black, Cloupor the tank worked straight away but on my newer, silver, one I had to loosen the screw on the Cloupur by a couple of turns (it's fully tightened on the black one) to stop it showing "Check atomiser", which is a bit strange as it worked before with the screw tightened.

At least I can get some hits with it now though, even if they only last 3s and don't have to keep using the leaky OCC coil or the bad tasting Nautilus 

[doveman]

May 29, 2016 9:47:06 GMT DiscoDes said:

I think you may have a short somewhere in your RBA base, as the Nautilus works fine (have you tried other atomisers?) it would not appear to be your device.

They are pretty cheap to replace, or put a wanted advert in the Classifieds section, there is a good chance that someone will sell you one if you wnt to get one quickly.

The Subtank and the Nautilus are the only two tanks I have that fit the Cloupor but as you say, the Nautilus works so the problem was clearly the RBA.

Thanks for the tip, I might look for someone selling a s/h one as it will be a while before the RBA I ordered from FT (along with a Crius tank, so I'll have another tank I can use if I run into problems in future) get here.

[Get Off My Cloud]

Might not be a clean contact between the base positive pin and the RBA positive pin.

[Greg]

May 29, 2016 11:12:19 GMT doveman said:

May 29, 2016 9:46:18 GMT Greg said:

If it's firing with no coil in then clearly you some kind of short or at least low resistance path. Based on what you've said I'd suggest you strip the RBA down to its component parts and clean them all thourougly and check none of your insulators have melted.

Thank. I didn't realise the RBA could be stripped down but after reading your post I looked into it and found the bottom post with the holes in it unscrews, so I stripped it down and gave everything a quick wash.

It's sort of working now. Without the coil it showed "Check atomiser" as expected and with the coil it fires now but cuts out after 2-3s. I've got two Cloupor minis and have set both to 4v/20w. When I fire it, the readout shows 0.51ohm and 3.20v. On my older, black, Cloupor the tank worked straight away but on my newer, silver, one I had to loosen the screw on the Cloupur by a couple of turns (it's fully tightened on the black one) to stop it showing "Check atomiser", which is a bit strange as it worked before with the screw tightened.

At least I can get some hits with it now though, even if they only last 3s and don't have to keep using the leaky OCC coil or the bad tasting Nautilus 

I guess before you took the RBA apart the centre screw was a little loose or the crud under the insulator prevented it being tightened up. Now it's all clean and tight the centre post of the RBA is likely a little less prominent and therefore shorter which in turn means your 510 positive pin is less prominent / shorter. Hence the need to loosen clouper 510 

[decoy]

few annoying things about subtank rba

the bottom of the rba head seems a smidge shorter than the occ coil and can cause the sorta probs your getting
take the rba outa the base and push the 510 up in the base(its not fixed so go gentle or it will pop out)

the deck is smaller than you think if you build your coils to big or high it will short out on the chimney

the centre pin in the rba can come lose causing probs like your getting
tighten the centre pin making shure the top part of the deck is positioned right and check it by fitting to the base with no coil fitted (you should get a no atty message if you get atty short or low you need to re aline the deck)

when removing the legs from the coil don't snip them off as this can leave a stump of wire sticking out and it may not touch the sides when cool but when in use it expands and causes a short
if using 0.3 or less wrap round the screws and rock it back and forth to snap it off and 0.4 and above seems to clamp ok passing it strait throw and rocking it to snap off

I discovered most of this when trying to use ni200 in the sodding thing hope it helps

[doveman]

Well I got fed up with it again this afternoon as it started only firing for anywhere between 0.3-2s before cutting out again, so I took it apart again and examined it properly. As you can see in this photo, it seems like part of the insulation ring has burnt away. I thought it might just be crud on top of the ring but I carefully scraped it away to find there was no ring left in that area. Happily though, after scraping the crud away, it's working normally again now and fires for as long as I hold the button Still I'll be glad when I receive the extra RBA atty and the Crius tank so that I have some alternatives in future.


Thanks for all the advice guys, it will help me setup my coils better, diagnose any future problems quicker and maybe even help me avoid damaging any more hardware.

[tim]

May 29, 2016 22:57:43 GMT doveman said:

Well I got fed up with it again this afternoon as it started only firing for anywhere between 0.3-2s before cutting out again, so I took it apart again and examined it properly. As you can see in this photo, it seems like part of the insulation ring has burnt away. I thought it might just be crud on top of the ring but I carefully scraped it away to find there was no ring left in that area. Happily though, after scraping the crud away, it's working normally again now and fires for as long as I hold the button Still I'll be glad when I receive the extra RBA atty and the Crius tank so that I have some alternatives in future.

That damage was caused by something shorting. Maybe a bit of wire from clipping the coil legs. Make sure you collect your off-cuts of wire. You never know where they might end up.

At least you weren't using a mech. That might have got a bit tasty.....