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View Full Version : Paraffin/Kerosene blowtorch preheating



Rowan Patel
03-23-2007, 06:40 PM
I've been wanting one of those old fasioned blowtorches which run on paraffin/kerosene for a while now. I want to see what fuel costs are like compared to propane and if it gets hot enough and is cheaper to run I'll try using it for brazing.

I bought one on ebay a few weeks ago (http://cgi.ebay.co.uk/Antique-Brass-Paraffin-Blowlamp-Blowtorch-by-Veritas_W0QQitemZ200082778901QQihZ010QQcategoryZ14 61QQrdZ1QQcmdZViewItem) and it finally came on Monday. I have read the liquid fuel blowtorches need to be preheated and my dad says they will need to be too. I know that some blowtorches have a tray underneath the torch head which you light some flammable liquid in to preheat the head. Mine doesn't have a tray on it though. I don't think it used to have one which has fallen off because there were many other blowtorches on ebay which were identicle to mine, and none of these had a tray either. If it does indeed need to be preheated there must have been some way which people used to preheat this type of torch. However I can't see any obvious way of preheating it. If anybody knows how to preheat the type of torch shown on the ebay link please tell me.

Thanks Rowan

Anon
03-23-2007, 10:17 PM
The blackened cylinder on the top should contain the mechanism for vaporizing the fuel. My guess would be to try to light it with a propane blowtorch, and heat the flame end of the vaporizing mechanism until it catches.

Rowan Patel
03-27-2007, 05:43 PM
I'll give it a go thanks, I would like to find a way to preheat without propane though and there must be someway they used to get these torches going because they are from a time when people didn't use propane torches. I suppose I could make a tray and attach it under the torch head...

Funes
03-28-2007, 08:25 AM
I've never got any I've bought to run - the pump part's often knackered. They were preheated by pouring meths into the indentation in the top and lighting it. A parafin soaked rag works too.

Some of the more dubious ones ( from a safety point of view ) ran on petrol and developed pressure by preheating to start the petrol boiling - I've never fancied firing one of those up.

Rowan Patel
03-28-2007, 04:55 PM
They were preheated by pouring meths into the indentation in the top and lighting it.

Thanks :D thats what I wanted to know.

It says on the ebay bid 'can still be used for its original purpose' so I'm hoping that it should work. If you pump the plunger the tank is pressurised and you can here a hiss as air escapes from the pipe which the fuel comes out of. I can't here a hiss of escaping air any where else around the fuel tank so I think it is ok.