[David Gardiner]

Like Bill said if your guages are knackered get them fixed or get new ones. It would be dangerouse to use them in that sort of condition. The correct setting for a tip of the size used for welding ally in 18 or 16g (1.2mm or 1.5mm) is as I said. If that can't be judged because the guages are old and not working its time to fix them.

If you were to have the settings at pressures of ten pounds or over you would have a lot of problems, you would tend to blow holes and your torch would emit a loud hissing sound, this is not correct. In fact that would be the case at anything over the correct settings getting worse as the pressures go up. If you could just guess at it you would not need the guages you would just have a valve.

For cutting 1/4 inch steel you would only need 25 lb of oxygen pressure! much less for the accetylene.

The main difference in single or two stage regulators is the ease of setting up and the stability of the flame, with single stage regulators, especially cheap ones they tend to need to be adjusted more regularly to keep the flame correct. not a real problem its just nice not to have to when you weld several hours every day like I do.