Can't maintain a stable flame with my torch

[Muggins2003]

Hi All,

I am using a Little Torch with propane and oxygen. When I light the flame and introduce the oxygen the pressure on the oxygen gauge reduces and the flame moves from being blue in colour to orange (indicating lower amounts of oxygen). I have checked for leaks but haven't found any and have tightened all connections to the point that they can't be tightened any further. The issue still remains and I haven't a clue how to fix it.

Just wondering if anybody would have any ideas? I've never replaced by oxygen tank before and don't really know the signs of when I should replace it but I've no problem increasing the pressure on the oxygen tank so not sure that it's emptying...........

Thanks for your help!

[Goldsmith]

May I ask what sort of oxygen regulator you are using? a standard regulator has two dials, one to regulate the pressure to the torch and the other to let you know how much is left in the cylinder. Like this model; http://www.amazon.co.uk/Oxygen-Gauge..._sim_sbs_diy_3

James

[Muggins2003]

I have a similar regulator. There's 2 dials. I didn't realise the other dial was to read what's left in the cylinder. I can now confirm that the cylinder isn't empty.

[Goldsmith]

Forgive me if I am stating the obvious, I take it you know that the central knob between the dials on the pressure gauge controls the pressure on the line to the torch. If the dial on the pressure line to the torch decreases when you turn on the oxygen and the knob on the torch, try turning the central pressure regulator knob clockwise and see if the outlet dial pressure increases. I use an oxygen setting of between 5 and 10 bar when using my little torch, the smaller the nozzle the lower the pressure needed. When I have finished soldering I always turn the pressure regulator knob off before turning off the oxy bottle knob.
I hope this all makes sense.

James

[Muggins2003]

Thanks James - that all makes sense. I use a size 7 tip and use 0.5 bar (maximum setting on regulator is 6 bar) and this is consistent with the instructions I have for the regulator and torch. I thought the function of the regulator was to ensure that the pressure of the oxygen stayed stable rather than having to turn the central knob in the middle of trying to solder. When I use similar equipment in the jewellery school I attend, the level of oxygen doesn't change in the flame unless I turn up or down the oxygen by moving the green nozzle on the torch. Apologies if I'm missing something obvious.........