oxy/propane brazing using a Sapphire 3 or Dh torch

[interlinkm74]

Hi,

I have a BOC Saffire 3 torch. I've just been told that mixer on a Sapphire 3 is set up for acetylene and does not mix properly for propane.

Its been suggested I get a Saffire lite or DH torch Since I have an oxygen and propane set up and i'm not switching to an oxy acetylene account.

My question is has anyone brazed with a standard Sapphire 3 torch and tips or got a comparision with a Sapphire lite or DH torch? Is it just about changing the mixer

Thanks

 

[migman123]

A Saphire 3 should work fine with oxy propane for brazing. I could be wrong but I've only ever seen a propane specific mixer for type5 torches and I've used loads of different oxy acetylene torches with oxy propane at work for heating seized bolts and brazing without any problems

 

[interlinkm74]

Thanks for thoughts. Sounds like its working just fine for you. Having done a bit of research now i'm kind of going to go with a propane specific mixer and nozzle. That way I know i'll be maximizing the lower temp of propane by getting the most efficient flame.

 

[sardine]

The standard tips are tricky to use with propane, you have to add the oxy very very slowly or it blows out the flame. A right PITA.

 

[brightspark]

they work ok but as said above. a bit finiky to set

 

[bambuko]

propane specific mixer and nozzle

Care to share the details?
I am using bog standard mixer and nozzles on my lightweight oxy-propane brazing setup, but if there is an improvement possible, I'd love to know.

 

[brightspark]

the mixer is just 2 in to one conection on the torch

 

[premmington]

I use a standard type5 torch with oxy-propane. You just need a bigger nozzle.

I do thou, use a propane regulator and orange propane hoses.

The propane mixers I have seen, are for big BTU pepperpot heating nozzles.

 

[bambuko]

the mixer is just 2 in to one conection on the torch

I know that much
I was just puzzled - what's the difference between mixer sold as "propane specific" and the "usual mixer"
With oxy-propane being as temperamental as it is (I use all nozzles from 1 to 13 for brazing, but mostly 3, 5 and 7) any trick that makes it easier is welcome.

... I do thou, use a propane regulator...

What makes a regulator into "propane regulator"?

 

[migman123]

I know that much
I was just puzzled - what's the difference between mixer sold as "propane specific" and the "usual mixer"
With oxy-propane being as temperamental as it is (I use all nozzles from 1 to 13 for brazing, but mostly 3, 5 and 7) any trick that makes it easier is welcome.


What makes a regulator into "propane regulator"?

I'm not sure but I think the propane mixers may have larger gas holes to allow higher flow to feed those propane super heating nozzles. The propane regulators also go up to higher outlet pressures than acetylene and apparently the diaphragm in a propane regulator is designed for use with lpg.

 

[interlinkm74]

Talking about regulators I was going to use my propane bottle regulator (with arrestor) one of those red ones which goes 0- 4 bar. Is 4 bar enough though?

In terms of the difference I understand that the mixer chamber size is different to allow the propane to flow properly and the preferred nozzle is a rosebud type multi jet nozzle, 1 centre orifice with smaller preheat flames surrounding the central orifice.

 

[migman123]

Talking about regulators I was going to use my propane bottle regulator (with arrestor) one of those red ones which goes 0- 4 bar. Is 4 bar enough though?

In terms of the difference I understand that the mixer chamber size is different to allow the propane to flow properly and the preferred nozzle is a rosebud type multi jet nozzle, 1 centre orifice with smaller preheat flames surrounding the central orifice.

0-4 bar is fine that's the same as I use at work.

 

[interlinkm74]

I know that much
I was just puzzled - what's the difference between mixer sold as "propane specific" and the "usual mixer"

I just read this on the wiki page about oxy/propane so though i'd copy this in. Seems as if the mixers are different.

'Propane often gets unfair criticism because it really needs changing the torch (from an equal pressure torch to an injector torch) and not just changing the tip to get the best performance. Most torches are equal pressure and designed for gases, such as acetylene, which are lighter than oxygen. Propane is a great deal heavier and runs much better through a low-pressure injector torch with a setting from a few ounces to about two pounds per square inch when cutting.'