blowtorch

Hello all.

I have a cheap magnum propane blowtorch. I made a little hearth to silver solder a tiny boiler and as the boiler got red just about ready to put the solder on the torch goes out. I am using it in a little shed. do you think i need to use it outside or do the hearth a bit different so it does not suffocate. the boiler was the corner.

Thanks

Henry

Was the shed door open or closed ?

You need to let the hearth breathe a bit - the burner had used all availible oxygen, hold torch further away for better results.

I think it may have been open but it is only a small shed.

If there was a lack of oxygen in your shed I think you would be physically aware. Sounds to me like a nearly empty gas canister. Regards, Michael.

I will have to have an experiment and see if it keeps going when i hold it outside ect. i think it may be lack of oxygen in the immediate area. i was thinking of putting a tube around the burner so it draws air nearer to my hand (further away from heat)

If the canister is not empty, the answer may well lie in your description of the torch - cheap!

Such torches can starve themselves of air as the cylinder tilts and becomes horizontal. The flame goes out.

What does the company that has your money say?

Regards

Keith

If the canister is not near empty or freezing, the answer is more likely in the mode of operation. Poster says ‘it suffocates’. Until that point, it would appear that the burner operates fine. Expensive burners are usually those with often not-needed extras.

The smaller burner has got air holes in the side and the bigger one i put on has air holes in the back and they both go out as soon as the boiler goes red so maybe it has got to do oxygen in that area. i did have the torch horizontal all the time when i was using it.

I find my torch goes out if I get it too near the back of the hearth. Moving the workpiece forward of the hearth normally does the trick.

I've had the same problem as Vic with Sievert torches. I think the combustion products get bounced back towards the torch and dilute the incoming air supply. A cyclone burner, which has the air input closer to the handle, helps but even this has problems in a confined area like firebox.

Rod

Yes mines a Sievert torch as well Rod. I use refractory bricks as a temporary “hearth” so maybe the reflected heat doesn’t help either. As I say though, moving the work away from the back of my hearth usually does the trick.

Thanks for the help everyone. i will just try putting a tube on the burner to see if it helps.

i turned the adjustable regulator down a bit and that seems to help a lot.