flame fluctuations

[LAJ]

I have a Knight Bullet Burner that I'm running with an M20 oxycon. I just got these both used so this is a new problem for me. I was previously on a minor with a 5LPM oxycon.

I'm having extreme (at least I think they're extreme) flame fluctuations with my new set up. You know how oxycons make those iron lung kind of sounds? Well, my flame changes in time with the sounds. There doesn't seem to be any way to control it. I didn't have this with my previous set up. Has anyone else experienced this? Any suggestions as to what I can do to "tame the flame"? Any help would be greatly appreciated.

[Dasi]

My machines are doing the same thing. I wish I had an answer for you.


I have a Knight Bullet Burner that I'm running with an M20 oxycon. I just got these both used so this is a new problem for me. I was previously on a minor with a 5LPM oxycon.

I'm having extreme (at least I think they're extreme) flame fluctuations with my new set up. You know how oxycons make those iron lung kind of sounds? Well, my flame changes in time with the sounds. There doesn't seem to be any way to control it. I didn't have this with my previous set up. Has anyone else experienced this? Any suggestions as to what I can do to "tame the flame"? Any help would be greatly appreciated.

[pam]

Hi Lea, is this with the inner ports only, or just when they are both open? If it works fine with the inner ports only open, then it is probably not getting enough oxygen for the outer flame.

Wale has this description on its website regarding an OG20.
(Center Fire) performs to capacity
(Outer Fire) run a neutral flame with candles at 3-4mm

I'm not sure what the difference is in the OG20 and the M20, but perhaps that may help a little.

If the torch is not running at capacity on just the inner rings, then I would contact the manufacturer of the concentrator. Perhaps they can help you.

[Lisi]

I had the "breathing flame" too, so I use a small holding tank to regulate the pressure flow from the machine. But I have a generator that no one else seems to have but me - an Airsep AS-12A, which is 15lpm at 18psi. I don't know of the company that you bought yours from sells small holding tanks or not, but I would check with them.

I also have a 5lpm concentrator and it doesn't ever "breathe" like that. I suppose now that you have a machine with a higher pressure output, that's what you are seeing.

[LAJ]

Thanks Pam & Lisi. Yeah, it's just the inside ports, at least I think it's only the inner ports. I haven't used the outer ones yet. I spoke with ABR earlier today. They gave me the contact info for the manufacturer. They suggested that I turn the flow down a bit, which I will try next time I torch, probably not till early next week :cry:. They said that if that didn't work, I'd have to send it in for them to look at it. I'm hoping the downward adjustment is all that's needed. I'll keep you posted.

[kbinkster]

What is likely going on is that you are using all the oxygen that the machine has built up in its internal storage tank and are running on the fly - meaning that as soon as each cylinder purges it's oxygen, it is being used up. There is a brief pause between when the first seive cylinder purges its oxygen and when the second one does. This pause is what causes that breathing and flame fluctuation. It is something that can happen with any two seive cannister concentrator when the internal storage tank is exhausted. Of course, if it is really a really extreme pause, there may be something going on with the machine. It could be because of the high pressure, or there could be something else. Talk to UO and see what they say.

You may not have had this issue with your previous set-up if you weren't pushing your Minor very hard. Or, it could just be that your centerfire is using quite a bit more oxygen - even if you're not pushing the torch. Knight says that the Bullet's centerfire uses up to 50 CFH (about 25 LPM) for its maximum flame. The M20 puts out 10 LPM. The Minor uses about 7 LPM. 25 to 10 is a lot different than 7 to 5 (if that makes sense). I need to test my Bullet Burner to see what it actually uses. I'm having a hard time believing that it actually goes through that much oxygen. But, then again, that's what the manufacturer is reporting.


As far as reducing the fluctuation... If it turns out that your unit is functioning fine and there's nothing UO can do, then you can do one of two things. You can get an external storage tank like Lisi suggested or you can get a second unit to supplement your first. If you go with an external storage tank, that will eliminate the fluctuations until you empty that tank. If you get a second unit of some kind, it will reduce the fluctuation and you will have more volume to feed your torch. Of course, you can hook two together and add a storage tank of you really want to power the torch even better. But, if you feel that your machine is not up to par, you may not want to invest in another.

If you reduce the flow at the machine, you will be putting less strain on the machine, no doubt, and that may help some of the breathing (and the purity will likely improve, too). But, you will not be able to have as large a flame. If you push the torch to where it is demanding that oxygen and you empty that internal storage tank, you could still have a breathing issue, just maybe not as severe.

[LAJ]

Thanks Kim for the great advice. I did lower the flow on the the concentrator and the fluctuations have stopped. The only thing is that I really like working hot so I opened up the outer flame too, which gave me the desired amount of heat, at least it seemed to. I am thinking of building myself a holding tank like the one in Trey's tute.

I have another question, I thought I read somewhere that the O2 hose should not run very far from your torch. I torch in my garage & therefore I'm working with a 25' hose to accomodate my propane tank which is stored outside. The hoses I have are linked as I think they all are. Correct me someone if I am wrong about this. I would have to separate it all the way practically to get a shorter connection to my oxycon. Could someone please post here with regards to this. I really don't want to separate out my hose if there's no need.

[artwhim]

Lea, Trey's tut is so easy to follow. I really noticed a difference once the holding tank was installed. It was a pretty cheap power boost.

[LAJ]

Thanks Kathy. Do you know if it's true that you have to keep the O2 line short? I REALLY don't want to have to separate out my hose which has the O2 & propane part attached, KWIM? I think they're all like this.

[pam]

Lea,
Basically the farther you have to push the oxy or propane, the more power you need to do it. At the Gathering we have run 100 foot hoses, but there is some drop in pressure and you have to compensate for that by turning the pressure up slightly. I'm not sure why you don't want to separate your hoses, but you would probably get slightly more oxy pressure at the torch if the hose was shorter.

[LAJ]

Thanks Pam. the only reason is that I'm nervous that I might cut through the hose accidentally & nicking it when I separate them, that's all. They look thick & all, but was just a bit leery about doing it. Though if I do separate them, I could leave the O2 one attached & not have to detach it each time so might have to get up my courage & try it.

[ginko]

Lea, you should be able to hold the red hose in one hand, the green in the other and just pull the hoses apart. Then you can cut one hose without risking the other.

[Hayley]

Lea - if I am understanding correctly of what you want to do, the hoses peel apart from each other by hand easily, there is not need to cut them. I have my oxycon to the left of my torch and the propane outside to my right - so the first thing I did upon getting the hoses was to peel them apart to about six inches from the torch connection.

[LAJ]

REALLY??? They peal apart? I was using an exacto knife to separate them out. I feel like such a dufus ](*,). That would sure make it easier.