"Jon Danniken" wrote:

Is my concern for the longevity of a stainless steel burner tip warranted?

I don't think so. Look at oxy/act equipment, far higher temperatures and the tips are
made of what looks to be copper to me.

The burning happens outside the tip with MAPP.

Wes

I'll offer some more description about the screw-on disposable tank-type
MAPP torch I've been using. The MAPP gas is meant to mix and burn within the
burner tube on all of them of this type that I've seen.
I know this seems weird, but the opening in the bigger mixer/burner "tip"
that I have is about 3/8" diameter. The last 2" of tube is where the
combustion begins.

I don't have any experience with a refillable cylinder, regulator and hose
type MAPP/air torch. I dunno if the construction has any similarities to the
screw-on type torch.

The orifice/jet is located at the base of the tube at a venturi (with
considerably larger air holes than a propane torch) where the gas flow draws
in air, then there is a twisted helix of sheet metal within the tube, which
I think is intended to swirl the mix to ensure that the air and the MAPP gas
are mixed.

Combustion begins to take place within the burner tube (in the last 2" of
length), which is why the end of the tube glows. Most of the flame that
exits the tube is blue, and extends quite a ways past the tube end,
especially when the regulator valve adjustment is close to wide open.

The smaller mixer/burner "tip" looks more like a conventional cutting torch
tip, only at the end, except the fluted center is set back inside about 1/8"
from the end of the stainless steel tube.
For this smaller tube, the combustion takes place outside/just beyond the
end of the fluted insert, so there is no red glow from the smaller tube/tip.

It should be mentioned here again, that connecting a MAPP gas tank to a
regular propane torch won't result in the same heat output as when MAPP gas
is used with a MAPP torch.
I haven't measured the temperature or heat output, but the performance is
about the same as just using propane, when using a propane torch.
As mentioned above, the air intake holes/ports at the venturi are much
larger on a MAPP torch, suggesting that the gas/air balance is a lot
different.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Wes" wrote in message
...
I don't think so. Look at oxy/act equipment, far higher temperatures and
the tips are
made of what looks to be copper to me.

The burning happens outside the tip with MAPP.

Wes

On 2009-03-07, Wild_Bill wrote:
I'll offer some more description about the screw-on disposable tank-type
MAPP torch I've been using. The MAPP gas is meant to mix and burn within the
burner tube on all of them of this type that I've seen.
I know this seems weird, but the opening in the bigger mixer/burner "tip"
that I have is about 3/8" diameter. The last 2" of tube is where the
combustion begins.

[ ... ]

It should be mentioned here again, that connecting a MAPP gas tank to a
regular propane torch won't result in the same heat output as when MAPP gas
is used with a MAPP torch.

O.K. I don't have a genuine MAPP torch.

I haven't measured the temperature or heat output, but the performance is
about the same as just using propane, when using a propane torch.

Hmm ... my own experience, using the same torch, but starting
with a tank of propane, and then switching to a tank of MAPP, that I
could do small silver soldering with the MAPP, but not with the propane,
which suggests a bit more heat available from the MAPP -- whether it is
a higher flame temperature, or just better transfer of energy to the
workpiece remains to be seen. The workpiece was not surrounded by
firebrick (I don't have any, yet), and it had to be clamped in a drill
press vise, with the second part held on with some copper wire while the
silver solder flowed.

As mentioned above, the air intake holes/ports at the venturi are much
larger on a MAPP torch, suggesting that the gas/air balance is a lot
different.

It might simply be that the MAPP torch in question is designed
to burn more fuel per unit time, so it needs more air for that.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

I'm fairly certain that this particular model of MAPP torch that I've been
using has a higher fuel delivery/burn rate than any propane torch I've used,
since the length of the blue flame extending from the swirl chamber/tip is
much larger diameter, longer and louder than with any propane torch.

I suspect that there are many variations in the designs of all the available
portable torches. I see some propane torches at stores now with huge burner
heads on them (over 1" diameter), when years ago, they all looked about the
same.

I haven't looked, but I would doubt that there are any readily available
specifications available for orifice sizes or CFH cu-ft/hour rates for these
portable torches.

My original reply was YMMV, as I would expect that there are many
differences in portable torches, especially related to cool-looking and
cheaper to manufacture products.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"DoN. Nichols" wrote in message
...
On 2009-03-07, Wild_Bill wrote:
I'll offer some more description about the screw-on disposable tank-type
MAPP torch I've been using. The MAPP gas is meant to mix and burn within
the
burner tube on all of them of this type that I've seen.
I know this seems weird, but the opening in the bigger mixer/burner "tip"
that I have is about 3/8" diameter. The last 2" of tube is where the
combustion begins.

[ ... ]

It should be mentioned here again, that connecting a MAPP gas tank to a
regular propane torch won't result in the same heat output as when MAPP
gas
is used with a MAPP torch.

O.K. I don't have a genuine MAPP torch.

I haven't measured the temperature or heat output, but the performance is
about the same as just using propane, when using a propane torch.

Hmm ... my own experience, using the same torch, but starting
with a tank of propane, and then switching to a tank of MAPP, that I
could do small silver soldering with the MAPP, but not with the propane,
which suggests a bit more heat available from the MAPP -- whether it is
a higher flame temperature, or just better transfer of energy to the
workpiece remains to be seen. The workpiece was not surrounded by
firebrick (I don't have any, yet), and it had to be clamped in a drill
press vise, with the second part held on with some copper wire while the
silver solder flowed.

As mentioned above, the air intake holes/ports at the venturi are much
larger on a MAPP torch, suggesting that the gas/air balance is a lot
different.

It might simply be that the MAPP torch in question is designed
to burn more fuel per unit time, so it needs more air for that.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---