Proper rosebud tip settings

[Nate Zukas]

For all the rosebud tip users here, could you guide me on a correct mixture settings. Wanting to use the rosebud for the broader heat and hopefully fewer filler entry points compared to a larger regular tip. My question is individual small coned flames or all the cones into a large flame? Pics below showing the two and my smith torch. Gas settings 20 on the oxy and 5 on the acetylene. Played around with both settings on a thick scrap piece of steerer tube, a lot faster heat up and definitely broader heat and both setting seem pretty easy to control the heat.
Thanks, NATE

DSCN0598 by Nate Zukas, on Flickr

DSCN0597 by Nate Zukas, on Flickr

DSCN0596 by Nate Zukas, on Flickr

DSCN0595 by Nate Zukas, on Flickr

[Eric Estlund]

I use it closer to one (although those individual cones look a little washed).

[Nate Zukas]

Hard to capture with the point and shoot but is this what your talking about?

DSCN0602 by Nate Zukas, on Flickr
Thanks! NATE

[claritycycler]

General google rosebud info:

https://www.google.com/search?q=Prop...hrome&ie=UTF-8

from one of the sites, FWIW:

QUESTION: I just purchased an oxygen/acetylene set up after stick/mig welding for a number of years in order to bend certain structures. Gas is a whole new beast. I was looking for instructions on how to adjust the flame for a rosebud (heating) tip. Thank you for any help you can offer!

ANSWER: Running a rosebud tip on acetylene has some real problems.
Acetylene tanks can produce a lot of gas, but not quickly, because they store their gas dissolved in acetone to stabilize it.
Extracting this gas from the acetone can't happen quickly.
This poses a problem with rosebud tips.
Rosebud (or multi-flame) tips come in a variety of sizes.
The medium to large rosebuds require a higher volume of gas than an acetylene tank can produce continuously, so they tend to backfire and "pop".
The problem is magnified if you are using a smaller acetylene tank, like those owned by most hobbyists and homeowners.
So if you are stuck with acetylene as your fuel gas you will be limited to only the smallest of rosebud tips
You can overcome this if you run several acetylene tanks in a manifold, all feeding to one regulator.
Obviously this is not a solution for a homeowner or hobbyist.

What I recommend is to run a rosebud tip on oxygen and PROPANE.
A little known fact is that you can attach an acetylene regulator onto any propane tank.
Even the small 5 gallon (20 lb.) BBQ bottles have internal threads in the valve head that accept a standard acetylene regulator.
This gives you access to a few other options as to oxy/fuel gas applications.

Because Propane is stored in a liquid form, it expands to a gas quickly, and in high volumes.
Even the largest rosebud tip can be fueled by a BBQ bottle without a problem.

Using oxygen with propane is a great combination for rosebud tips, but also works great for cutting.
When oxygen and acetylene burn the highest heat is at the tip of the inner blue cones, and this flame is just around 5800 degreesF.
Steel melts around 3100 degreesF so there is more than enough heat to melt steel.
This works well for welding, but for all other applications LP gasses, like Propane, actually work better.
When you burn oxygen with propane the highest heat is actually 3/4" to 1-1/2" from the tip.
This means you have more heat further from the tip, which works much better for cutting heavy plate steel than acetylene.
Also LP gases don't burn as hot as acetylene (between 5100 and 5500 degF) so you have less trouble with over heating the steel, leading to rounded cut edges and over melting of thin steel.
You will need propane cutting tips, since they are quite different from acetylene cutting tips.

The one thing you can't do with propane, or any LP gas, is weld.
When LP gasses burn with oxygen they infuse too much hydrogen into the flame to allow gas welding of steel, and the welds would end up quite brittle.

Back to your original question about adjusting a rosebud tip...
You need the fuel gas to be roaring, loud with no soot showing, before you add oxygen.
The flame should pull back to the tip as you add oxygen, until you have a ring of small blue cones.
Rosebuds are LOUD when adjusted correctly.

[Eric Estlund]

Yup- they roar. Any multiport tip for the AW1A will be smallish in the scheme of these things- you'll be ok (but may need to up your flow rate).

[Nate Zukas]

Thanks for your help Eric!
claritycycler , Thanks for the info also, big help. Got a good roar going on now with very nice small blue cones.
Thanks y'all! NATE

[Eric Estlund]

Now just keep it moving...