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Acetylene & soot


#1

Hi everyone - In one of the recent posts it was mentioned that a
torch using acetylene would only produce soot if there wasn’t a
correct mix of fuel and air. I have a Smith Little Torch
Oxy/Acetylene setup, and when I first light the torch I get tons
of soot everywhere. I always assumed this was inevitable but if
someone tells me there’s a way to avoid it I’d very happily listen!

Best,
Jessica in San Francisco, busy a-sawin’ and a-soldering and a-filin’…


#2

Regarding lighting an acetylene torch without producing soot…Just
open the oxygen valve a little before you light the torch. You may
then readjust the torch for your job. You will soon get a feel for
the correct amount to open the valve to eliminate soot and still
light the torch. And remember that with oxygen open the gax mixture
can be expolsive so light the torch very soon after opening the
valve. G


#3

i have been reading the posts about acetylene and soot with great
interest as I recently purchased an acetylene Smith torch
(Silversmith), with a handy heat torch tip to use in casting. I
am used to my ancient and trusy old Prestolite, and was
flabergasted at what happened when I lit the Smith torch intending
to use the handy heat tip for melting some silver prior to casting…
I thought I was following all the directions (vague as they were)
faithfully, but got a foot or more of flame shooting out the torch
tip, a huge cloud of soot, and the tip got too hot to
hold—sizzling hot. I immediately shut it off at the torch and
my friend who was casting with me, quickly shut down the valve on
the tank. I did contact Smith via email, and got some assistance,
but not enough so that I feel comfortable using the torch. Can
anyone give me specific instructions on how to light it. I was
told to give the key 2 full turns, then to open the knob on the
torch tip, then to light it. Is this correct?. My old prestolite
was so simple, I just set the valve on the B setting, and left it
there, Then when I needed to use the torch, just gave the tank key
a quarter turn, opened the knob on the tip, lit it, adjusted the
flame and that was it. Not so with the Smith. what am I doing
wrong:?.

thanks for all your help. Alma


#4

Hi Alma,

I suspect that the instructions depend on the type of regulator
you’re using. I’m also assuming you’re using the acetylene/AIR (vs.
acet/OXY) setup for that Smith torch. If so, I have the same torch,
and these instructions apply – if not, then ignore them!

If you’re using acetylene/air, 2 turns of the tank key is WAY too
much – which could lead to exactly the symptoms you’re describing.

I also have a flashback arrestor installed (which is always a good
idea) between the regulator and the hose leading out to the torch.
The flashback arrestor does reduce the flow of gas, by as much as
25%, so you may have to turn on the gas a little more than you’re
used to doing with your Prestolite if you have it. BUT … other
than that, your settings should be the same.

I turn my tank key about 1/3 of the way, turn the regulator knob
about 2/3 of a turn, then turn the knob on the torch tip just enough
to be able to QUIETLY hear the gas, and finally use the sparker to
light it. If set up correctly, you shouldn’t see soot, a yellow
flame, or anything other than a steady blue flame. The larger the
torch the louder the “pop” when it lights, but it shouldn’t sound
like a car backfiring, either. The torch tip shouldn’t overheat.

As I said, if you’re not on an acetylene/air system, then there may
be something else going on in your setup, and IGNORE these comments!

Karen Goeller @Karen_Goeller


#5

Alma, try using the same procedure on the Smith as you did on the old
Prest-O-Lite. A quarter-turn on the B tank should give you enough
gas to work with. Then turn the knob on the Smith just enough to get
a smooth gas flow before lighting it. After that, adjust the flame
as needed. If the flame is too yellow or sooty,you may have to alter
the air adjustment on your regulator till you get the correct flame.
Also make sure the torch tip is correctly inserted
into the handle. Hope this helps. Dee


#6

Alma, do you have OXYGEN hooked up to your Handy Heet (SMITH) torch?
It’s supposed to be an acetylene/ambiant air torch. Or are you using
a Smith Mini Torch with a Handy Heet tip? I don’t think you should
be doing that!!!


#7

the torch I am having problems with does not have a separate Oxygen
tank. It just has the one tank which contains acetylene It is a
"B" tank and has one regulator on it. . The Torch outfit is
called Silver Smith Acetylene and Air Soldering kit. It is exactly
like the kit shown in the Rio grande catalog on p. 341. In
additiion I purchased the Handi-heet tip to use for casting. I got
my outfit from our local welding supply shop, and was assured by
them that I could use the Handi-Heet tip with my set-up. i then
conctact smith to verify this and was told that it was o.k. to
use the handi-heet tip with my hoses and tank. However, as i said
in my earlier post, when I lit it I got tons of black soot billowing
out, a huge foot long flame, and torch tip became too hot to hold.
It was actually sizzling hot. We shut everything down, and I sent
an email to smith regarding the problem. The answer was not helpful.
Hence my plea to you orchidians for some assistance. I must not
be operating it correctly. According to the instructions which I
followed carefully, I turned the regulatoradjusting knob to the
left (counter clockwise) in order to release the spring tension. i
then opend the tank valvewith the tank key–giving it the
recommended 1/4 to 1/2 turn. I then turned the regulatoradjusting
knob to the right two turns to obtain working pressure. I then
opened the torch valve, lit it, and kaboom, out shot the soot and
flame. What did I do wrong???/ thanks for your offer to help.
Alma


#8
    Prest-O-Lite.  A quarter-turn on the B tank should give you
enough gas to work with.   Also make sure the torch tip is
correctly inserted into the handle. 

Alma, Dee’s advice above is excellent. Also, be sure that your
torch tip is real clean. I remember in one class having a torch tip
that burned and smoked and we discovered that some sort of small bug
had “nested” inside the torch tip! Yuk! but once cleaned out,
everything was fine again. Also if you don’t have one, do get a flash
back arrestor.

Kay


#9

I am not familiar with the Smith torch… does it produce a roaring
noise when running right and an intense blue flame? I have used a
Turbotorch which is air Fuel type that creates a lot of turbulence
to get a hotter and more intense flame. On that type there is a
removable orifice inside the tip that is removed from the bottom.
When there is even a little debris on or in that orifice the air
pattern is bad and the torch will behave like yours did. I have
successfully cleaned them out with the proper sized drill bit (It
must be the exact size) or you can get replacement orifices (?)

Dan
Wellman


#10

Alma, I don’t know if this will help, but once or twice in the past
I’ve installed a tip on my Prestolite which did not have the little
screw in filter in it and got the same results you did. The
Prestolite is the same sort of setup you describe, a “B” tank with a
single stage regulator. Lok in the base of the tip and see if there
is a little metal screen looking thing. If not, and the gas is
unimpeded directly from the regulator through the tip, you’ll get
the heavy black soot etc. and I believe it’s a serious danger.
Jerry in Kodiak


#11
 I then turned the regulatoradjusting knob to the right two turns
to obtain working pressure. I then opened the torch valve, lit it,
and kaboom, out shot the soot and flame. What did I do wrong???? 

Sounds to me as though you

1.turned the adjusting knob too far (too much pressure) and/or

  1. opened the torch too far before lighting it. Start with way less
    gas, and sneak up on the right settings!

HTH
–Noel


#12
     According to the instructions which  I followed carefully,  I
turned the regulatoradjusting knob to the left (counter clockwise) 
in order to release the spring tension. i then opend the  tank 
valvewith the tank key--giving it the recommended  1/4 to 1/2 turn.
  I then turned the regulatoradjusting knob to the right two turns
to obtain working pressure. I   then opened the torch valve, lit
it, and kaboom, out shot the soot and flame.  What  did I do
wrong????/   thanks for your offer to help. Alma 

Alma, You’ve got exactly the same setup as I have. And from your
description of your actions, I think I know the issue. Releasing the
spring tension on the regulator is opening the pressure completely to
flow too much gas into the line, making your mixture way too rich in
fuel.

Here’s my operating procedure for startup (which I’ve done with all
the tips and not had any problem) and shutdown. I do, by the way,
have a flashback arrestor installed, so step 3 of startup is a bit
further than I’d turn without the arrestor in place.

STARTUP

  1. Make sure torch knob is off, and turn regulator adjusting knob to
    the right as far as it will go (don’t force it) to close it down.

  2. Turn tank key about 1/3 turn counter-clockwise. (you should see
    pressure indicator on the regulator move)

  3. Turn regulator adjusting knob ALMOST 1 turn counter-clockwise.

  4. Put on a torch tip, open torch knob for a couple of seconds to
    allow acetylene to flow down the tubes, then light.

SHUTDOWN

  1. Turn tank key firmly clockwise (you need to give it a decent
    amount of pressure to make sure it’s really off).

  2. Open torch knob fully, pointing into ventilation system, to
    bleed all gas out of the lines. Keep open until you don’t hear any
    gas, and until the regulator’s pressure gauge is indicating no
    pressure.

  3. Shut torch knob completely.

  4. Turn regulator adjusting knob counterclockwise as many turns as
    it takes to feel the spring tension release.

Hope this helps!
Karen Goeller
@Karen_Goeller


#13

Hi Alma,

 I got my outfit from our local welding supply shop, and  was
assured by them that I could use the Handi-Heet tip with  my
set-up.

Probably the quickest way to find out what the problem is, is to
turn the gas off at the tank, remove the regulator from the tank &
then take the whole thing back to the welding supply you got it
from.

If they’re like most places, they’ll be more than happy to help you.
They don’t want any unhappy customers.

From your description of the problem, it sounds as if there may be
some kind of obstruction in the air passage. As the torch is
designed, the air passage is large enough to prevent the sooting
that you’re encountering.

Dave


#14

Thanks to all who sent in suggestions about the soot and excessive
flaming of my handi-heet torch. I contacted Smith equipment again,
and found the problem is that although both the Silver smith and
handi heat torches are similar, I do need a different regulator
for the handi-heat torch tip. In other words, I am not getting
enough gas flow with the regulator I have been using which came
with my Silver smith kit. Thanks again to all of you. Alma


#15
        the torch I am having problems with  does not have a
separate Oxygen tank. It just has the one tank which contains
acetylene   It is a "B" tank  and  has one regulator  on it. .
Prest-O-Lite.  A quarter-turn on the B tank should give you enough
gas to work with. Also make sure the torch tip is correctly
inserted into the handle. 

Hi, I don’t know this particular torch but two things occur to me -
first I wonder if this is a problem with setting up a pressure
regulator. The Acetylene pressure needs to be regulated to just a few
psi - the foot-long flame seems a bit excessive. Secondly, is the
acetylene cylinder upright - it must be as the acetylene is dissolved
in acetone which can get blown out if the cylinder isn’t vertical
(dangerous as you effectively have a flame thrower!!) I would suggest
that, for your own safety, you find someone locally who uses an
acetylene torch - maybe a garage, and ask them to take a look at
your setup.

Best wishes,
Ian
Ian W. Wright
Sheffield, UK


#16

Hello,
I am having an issue with acetylene soot and found this old thread. Hoping someone will be able to help me trouble shoot. I have an acetylene/oxygen system (smith little torch) and have tried using both gases as well as acetylene solo, both with abundant amounts of soot while operating the torch. It gets everywhere which is pretty aggravating. How do I substantially reduce the soot while using acetylene? It’s there whether or not I use the oxygen. I plan to shift to propane eventually, but for now I’m stuck with what I’ve got.
Thanks!
Andrea


#17

Hi Andrea,

If you have natural gas in your studio you will find that it is cleaner than either acetylene or propane, half the cost of either gas and you’ll never run out of fuel! A G-TEC TB-15 Torch Booster will help you get great performance from your Little Torch. http://www.safe-t-gas.com/AdvantagesJM.html

Ed Howard
Sales/Marketing Manager
G-TEC Natural Gas Systems
ehoward@gas-tec.com
Visit www.safe-t-gas.com for jewelry manufacturing and glass lampworking applications


#18

Andrea,

You seriously should get an exhaust system to catch and vent your fumes and soot. I built one and have no issues whatsoever. You’re probably inhaling what you see as soot everywhere, and that’s not good for your lungs. I’m an oxt-acetylene girl with a Smith little torch, too.

Eileen


#19

Hi Andrea,

Aside from my well document mishaps I use a Smith Little Torch with propane, not acetylene. I used acetylene in a Prestolite torch for decades. This is what I brought to jewelry making from building commercial fishing boats. The soot worms in the air are a problem with acetylene but solvable. When you light the torch open the Propane/Acetylene valve a small bit but also crack the O2 side by just a tiny bit. Less than the gas valve. You’ll get a few pops of gas until you find the right mix. But this technique will significantly limit the soot production. There is a learning curve to just the right amount of O2 to add.

I suspect you may hear this technique has its detractors. Even at least one Youtube tutorial has you opening the gas and lighting it first and then adding the O2. The method I have described is how I light the torch and it works fine. I just have to remember it is a Little Torch and not a Victor pattern cutter.

Don Meixner

---- Andrea Shipley orchid@ganoksin.com wrote:


#20

Poops, my torch is a prestolite.

Eileen