I finally dug out the $2 garage sale Craftsman (really Harris)
oxy-acetylene cutting torch. It came with a cutting head of unknown size
which I just cleaned out and #7 torch tip.

It passes the soapy leak test when pressurized, and the o-rings appear ok.

I've not used one of these before but have run into a problem.

I set the acetylene until the flame is not a smoky mess. Then I add oxygen
at the cutting attachment valve (It's wide open on the torch handle) then
I push the cutting lever and the flame gets really vicious. When let go of
the cutting lever, the thing goes BANG and the flame goes out.

What might be going on here? I've got a new set of torch side flashback
preventers to attach before I play with this more.

The welding forums go on about how this is backfire vs. backflash and that
the torch is leaking air or the O2 pressure is too low or something is
broken. It's all vague.

I had the O2 as about 10PSI at the regulator and the acetylene around 5.
Not sure if these are correct-ish.

Suggestions?

"Cydrome Leader" wrote in message
...
I finally dug out the $2 garage sale Craftsman (really Harris)
oxy-acetylene cutting torch. It came with a cutting head of unknown size
which I just cleaned out and #7 torch tip.

It passes the soapy leak test when pressurized, and the o-rings appear ok.

I've not used one of these before but have run into a problem.

I set the acetylene until the flame is not a smoky mess. Then I add oxygen
at the cutting attachment valve (It's wide open on the torch handle) then
I push the cutting lever and the flame gets really vicious. When let go of
the cutting lever, the thing goes BANG and the flame goes out.

What might be going on here? I've got a new set of torch side flashback
preventers to attach before I play with this more.

The welding forums go on about how this is backfire vs. backflash and that
the torch is leaking air or the O2 pressure is too low or something is
broken. It's all vague.

I had the O2 as about 10PSI at the regulator and the acetylene around 5.
Not sure if these are correct-ish.

Suggestions?


Acet around 5 is OK , bump that O2 pressure to more like 20-25 and try
again . The preheat flame should not change when you depress to oxy feed to
start a cut . To set acet pressure open the torch valve all the way ,
increase pressure until the flame starts to pull away from the head then
back off until it comes back . Should be no smoke/soot from it if properly
adjusted . Oxy pressure is going to vary with the tip size and thickness cut
, but 20-25 is a good place to start .
--
Snag
I got this info from somewhere on the net , probably either here or SEJW ,
and while I don't recall the author I did respect his opinion .

"Terry Coombs" wrote in message
...

"Cydrome Leader" wrote in message
...
I finally dug out the $2 garage sale Craftsman (really Harris)
oxy-acetylene cutting torch. It came with a cutting head of unknown
size
which I just cleaned out and #7 torch tip.

It passes the soapy leak test when pressurized, and the o-rings
appear ok.

I've not used one of these before but have run into a problem.

I set the acetylene until the flame is not a smoky mess. Then I add
oxygen
at the cutting attachment valve (It's wide open on the torch
handle) then
I push the cutting lever and the flame gets really vicious. When
let go of
the cutting lever, the thing goes BANG and the flame goes out.

What might be going on here? I've got a new set of torch side
flashback
preventers to attach before I play with this more.

The welding forums go on about how this is backfire vs. backflash
and that
the torch is leaking air or the O2 pressure is too low or something
is
broken. It's all vague.

I had the O2 as about 10PSI at the regulator and the acetylene
around 5.
Not sure if these are correct-ish.

Suggestions?


Acet around 5 is OK , bump that O2 pressure to more like 20-25 and
try again . The preheat flame should not change when you depress to
oxy feed to start a cut . To set acet pressure open the torch valve
all the way , increase pressure until the flame starts to pull away
from the head then back off until it comes back . Should be no
smoke/soot from it if properly adjusted . Oxy pressure is going to
vary with the tip size and thickness cut , but 20-25 is a good place
to start .
--
Snag
I got this info from somewhere on the net , probably either here or
SEJW , and while I don't recall the author I did respect his opinion
.

Since s.e.j.w hasn't helped I'll repost this he

I bought an old Victor portable welding kit with a J28 torch, 2-W-J
welding tip and Uniweld 17-15 rosebud, which apparently consume
acetylene much too fast for the MC tank in the carrier. According to
Victor only a size 000 tip is within spec, but which size tip do
people really use for light welding like thermocouples and auto body
rust repair?

http://victortechnologies.com/IM_Upl...B)_Jul2011.pdf

jsw

On Mon, 14 Apr 2014 20:02:24 +0000 (UTC), Cydrome Leader
wrote:

I finally dug out the $2 garage sale Craftsman (really Harris)
oxy-acetylene cutting torch. It came with a cutting head of unknown size
which I just cleaned out and #7 torch tip.

It passes the soapy leak test when pressurized, and the o-rings appear ok.

I've not used one of these before but have run into a problem.

I set the acetylene until the flame is not a smoky mess. Then I add oxygen
at the cutting attachment valve (It's wide open on the torch handle) then
I push the cutting lever and the flame gets really vicious. When let go of
the cutting lever, the thing goes BANG and the flame goes out.

What might be going on here? I've got a new set of torch side flashback
preventers to attach before I play with this more.

The welding forums go on about how this is backfire vs. backflash and that
the torch is leaking air or the O2 pressure is too low or something is
broken. It's all vague.

I had the O2 as about 10PSI at the regulator and the acetylene around 5.
Not sure if these are correct-ish.

Suggestions?

O2 should be 15+, acety is correct

Sounds indeed like you have a leak somewhere in the head.

...put your finger over the end of the torch tip, turn on the gas..o2
then Acet.....then stick the entire thing into a bucket of water and
look for the bubbles.

Harris is pretty good torch stuff, Ive got several...and they work
nicely.

Ive seen the backfire before on a torch with a bad tip and a bad seal
around the torch tip body. Check inside the torch handle for a ding
in the sealing area..and check for the same inside the head of the
torch where the tip goes in. And are you sure..sure you have the
right tip? Some are close...some of the old National Carbonic tips
look almost identical..but dont fit perfecticly

Gunner









--

"
I was once told by a “gun safety” advocate back in the Nineties
that he favored total civilian firearms confiscation.
Only the military and police should have weapons he averred and what did I think about that?

I began to give him a reasoned answer and he
cut me off with an abrupt, “Give me the short answer.”

I thought for a moment and said, “If you try to take our firearms we will kill you.”"

---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

Gunner Asch writes:

On Mon, 14 Apr 2014 20:02:24 +0000 (UTC), Cydrome Leader
wrote:

I had the O2 as about 10PSI at the regulator and the acetylene around 5.
Not sure if these are correct-ish.

Suggestions?

O2 should be 15+, acety is correct

I'm using a Craftsman cutting torch bought in 1967. Never had the
problem you describe. But I do usually run it at 5 Acet/15-20 Oxy.

FWIW, the regulators for this set died years ago, repair guys
disclaimed being able to get parts. The roech handle, cutting and
weldeing heads just go on and on.

--
Mike Spencer Nova Scotia, Canada

Mike Spencer wrote:

Gunner Asch writes:

On Mon, 14 Apr 2014 20:02:24 +0000 (UTC), Cydrome Leader
wrote:

I had the O2 as about 10PSI at the regulator and the acetylene around 5.
Not sure if these are correct-ish.

Suggestions?

O2 should be 15+, acety is correct

I'm using a Craftsman cutting torch bought in 1967. Never had the
problem you describe. But I do usually run it at 5 Acet/15-20 Oxy.

I suspect this one is from 1983, and I'd be the second owner. I bought
hoses for it as I didn't have any B sized ones, and I already had
regulators.

FWIW, the regulators for this set died years ago, repair guys
disclaimed being able to get parts. The roech handle, cutting and
weldeing heads just go on and on.

They were doing railroad work by me so I asked the workers for some of
those large plates the rails sit on. They seemed to have problems hearing
me until I explained I want them to practive with a cutting torch. They
they just started to hand them over the fence. It was sort of amusing.

"Cydrome Leader" wrote in message
...
I finally dug out the $2 garage sale Craftsman (really Harris)
oxy-acetylene cutting torch. It came with a cutting head of unknown
size
which I just cleaned out and #7 torch tip.

It passes the soapy leak test when pressurized, and the o-rings
appear ok.

I've not used one of these before but have run into a problem.

I set the acetylene until the flame is not a smoky mess. Then I add
oxygen
at the cutting attachment valve (It's wide open on the torch handle)
then
I push the cutting lever and the flame gets really vicious. When let
go of
the cutting lever, the thing goes BANG and the flame goes out.

What might be going on here? I've got a new set of torch side
flashback
preventers to attach before I play with this more.

The welding forums go on about how this is backfire vs. backflash
and that
the torch is leaking air or the O2 pressure is too low or something
is
broken. It's all vague.

I had the O2 as about 10PSI at the regulator and the acetylene
around 5.
Not sure if these are correct-ish.

Suggestions?

This is the Harris gas welding and cutting manual:
https://www.google.com/search?hl=en&....0.a4TNmmcPg2I

On Monday, April 14, 2014 3:02:24 PM UTC-5, Cydrome Leader wrote:
I finally dug out the $2 garage sale Craftsman (really Harris)

oxy-acetylene cutting torch. It came with a cutting head of unknown size

which I just cleaned out and #7 torch tip.



It passes the soapy leak test when pressurized, and the o-rings appear ok.



I've not used one of these before but have run into a problem.



I set the acetylene until the flame is not a smoky mess. Then I add oxygen

at the cutting attachment valve (It's wide open on the torch handle) then

I push the cutting lever and the flame gets really vicious. When let go of

the cutting lever, the thing goes BANG and the flame goes out.



What might be going on here? I've got a new set of torch side flashback

preventers to attach before I play with this more.



The welding forums go on about how this is backfire vs. backflash and that

the torch is leaking air or the O2 pressure is too low or something is

broken. It's all vague.



I had the O2 as about 10PSI at the regulator and the acetylene around 5.

Not sure if these are correct-ish.



Suggestions?

You probably have 6920 cutting tips (most common) on your torch. Make sure that the tip is clean (use a cutting tip cleaner). Regulator pressure depends upon the tip number that you're using (stamped on tip barrel). See:
http://www.harrisproductsgroup.com/~...onCUTTING.ashx

wrote:
On Monday, April 14, 2014 3:02:24 PM UTC-5, Cydrome Leader wrote:
I finally dug out the $2 garage sale Craftsman (really Harris)

oxy-acetylene cutting torch. It came with a cutting head of unknown size

which I just cleaned out and #7 torch tip.



It passes the soapy leak test when pressurized, and the o-rings appear ok.



I've not used one of these before but have run into a problem.



I set the acetylene until the flame is not a smoky mess. Then I add oxygen

at the cutting attachment valve (It's wide open on the torch handle) then

I push the cutting lever and the flame gets really vicious. When let go of

the cutting lever, the thing goes BANG and the flame goes out.



What might be going on here? I've got a new set of torch side flashback

preventers to attach before I play with this more.



The welding forums go on about how this is backfire vs. backflash and that

the torch is leaking air or the O2 pressure is too low or something is

broken. It's all vague.



I had the O2 as about 10PSI at the regulator and the acetylene around 5.

Not sure if these are correct-ish.



Suggestions?

You probably have 6920 cutting tips (most common) on your torch. Make sure that the tip is clean (use a cutting tip cleaner). Regulator pressure depends upon the tip number that you're using (stamped on tip barrel). See:
http://www.harrisproductsgroup.com/~...onCUTTING.ashx

That looks about right. The cutting tip I have is apparently stamped "1",
so the chart indicates 35-40 PSI for the oxygen.

I did finally unscrew it from the torch head and there are half shiny
metal/half dark looking surfaces where the tip mates with the head. I'm
going to assume this is no good and it needs to be cleaned or corrected
somehow. Links to the photos are below:

the torch itself

http://www.panix.com/~presence/torch.JPG

the mating surfaces of the tip

http://www.panix.com/~presence/tip-seat.JPG

On Tuesday, April 15, 2014 6:05:44 PM UTC-5, Cydrome Leader wrote:
wrote:

On Monday, April 14, 2014 3:02:24 PM UTC-5, Cydrome Leader wrote:

I finally dug out the $2 garage sale Craftsman (really Harris)



oxy-acetylene cutting torch. It came with a cutting head of unknown size



which I just cleaned out and #7 torch tip.







It passes the soapy leak test when pressurized, and the o-rings appear ok.







I've not used one of these before but have run into a problem.







I set the acetylene until the flame is not a smoky mess. Then I add oxygen



at the cutting attachment valve (It's wide open on the torch handle) then



I push the cutting lever and the flame gets really vicious. When let go of



the cutting lever, the thing goes BANG and the flame goes out.







What might be going on here? I've got a new set of torch side flashback



preventers to attach before I play with this more.







The welding forums go on about how this is backfire vs. backflash and that



the torch is leaking air or the O2 pressure is too low or something is



broken. It's all vague.







I had the O2 as about 10PSI at the regulator and the acetylene around 5.



Not sure if these are correct-ish.







Suggestions?



You probably have 6920 cutting tips (most common) on your torch. Make sure that the tip is clean (use a cutting tip cleaner). Regulator pressure depends upon the tip number that you're using (stamped on tip barrel). See:

http://www.harrisproductsgroup.com/~...onCUTTING.ashx



That looks about right. The cutting tip I have is apparently stamped "1",

so the chart indicates 35-40 PSI for the oxygen.



I did finally unscrew it from the torch head and there are half shiny

metal/half dark looking surfaces where the tip mates with the head. I'm

going to assume this is no good and it needs to be cleaned or corrected

somehow. Links to the photos are below:



the torch itself



http://www.panix.com/~presence/torch.JPG



the mating surfaces of the tip



http://www.panix.com/~presence/tip-seat.JPG

Maybe try cleaning the mating surfaces with some fine steel wool. Check for daylight between the mating surfaces or mark the mating surfaces with a colored marker to see how they seal.

On Wed, 16 Apr 2014 06:45:26 -0700 (PDT),
wrote:

On Tuesday, April 15, 2014 6:05:44 PM UTC-5, Cydrome Leader wrote:
wrote:

On Monday, April 14, 2014 3:02:24 PM UTC-5, Cydrome Leader wrote:

I finally dug out the $2 garage sale Craftsman (really Harris)



oxy-acetylene cutting torch. It came with a cutting head of unknown size



which I just cleaned out and #7 torch tip.







It passes the soapy leak test when pressurized, and the o-rings appear ok.







I've not used one of these before but have run into a problem.







I set the acetylene until the flame is not a smoky mess. Then I add oxygen



at the cutting attachment valve (It's wide open on the torch handle) then



I push the cutting lever and the flame gets really vicious. When let go of



the cutting lever, the thing goes BANG and the flame goes out.







What might be going on here? I've got a new set of torch side flashback



preventers to attach before I play with this more.







The welding forums go on about how this is backfire vs. backflash and that



the torch is leaking air or the O2 pressure is too low or something is



broken. It's all vague.







I had the O2 as about 10PSI at the regulator and the acetylene around 5.



Not sure if these are correct-ish.







Suggestions?



You probably have 6920 cutting tips (most common) on your torch. Make sure that the tip is clean (use a cutting tip cleaner). Regulator pressure depends upon the tip number that you're using (stamped on tip barrel). See:

http://www.harrisproductsgroup.com/~...onCUTTING.ashx



That looks about right. The cutting tip I have is apparently stamped "1",

so the chart indicates 35-40 PSI for the oxygen.



I did finally unscrew it from the torch head and there are half shiny

metal/half dark looking surfaces where the tip mates with the head. I'm

going to assume this is no good and it needs to be cleaned or corrected

somehow. Links to the photos are below:



the torch itself



http://www.panix.com/~presence/torch.JPG



the mating surfaces of the tip



http://www.panix.com/~presence/tip-seat.JPG

Maybe try cleaning the mating surfaces with some fine steel wool. Check for daylight between the mating surfaces or mark the mating surfaces with a colored marker to see how they seal.
Water based only. NOTHING containing any oil or flamible materials
near oxygen.

On Wednesday, April 16, 2014 8:23:05 PM UTC-5, Clare wrote:
On Wed, 16 Apr 2014 06:45:26 -0700 (PDT),

wrote:



On Tuesday, April 15, 2014 6:05:44 PM UTC-5, Cydrome Leader wrote:

wrote:



On Monday, April 14, 2014 3:02:24 PM UTC-5, Cydrome Leader wrote:



I finally dug out the $2 garage sale Craftsman (really Harris)







oxy-acetylene cutting torch. It came with a cutting head of unknown size







which I just cleaned out and #7 torch tip.















It passes the soapy leak test when pressurized, and the o-rings appear ok.















I've not used one of these before but have run into a problem.















I set the acetylene until the flame is not a smoky mess. Then I add oxygen







at the cutting attachment valve (It's wide open on the torch handle) then







I push the cutting lever and the flame gets really vicious. When let go of







the cutting lever, the thing goes BANG and the flame goes out.















What might be going on here? I've got a new set of torch side flashback







preventers to attach before I play with this more.















The welding forums go on about how this is backfire vs. backflash and that







the torch is leaking air or the O2 pressure is too low or something is







broken. It's all vague.















I had the O2 as about 10PSI at the regulator and the acetylene around 5.







Not sure if these are correct-ish.















Suggestions?







You probably have 6920 cutting tips (most common) on your torch. Make sure that the tip is clean (use a cutting tip cleaner). Regulator pressure depends upon the tip number that you're using (stamped on tip barrel). See:



http://www.harrisproductsgroup.com/~...onCUTTING.ashx







That looks about right. The cutting tip I have is apparently stamped "1",



so the chart indicates 35-40 PSI for the oxygen.







I did finally unscrew it from the torch head and there are half shiny



metal/half dark looking surfaces where the tip mates with the head. I'm



going to assume this is no good and it needs to be cleaned or corrected



somehow. Links to the photos are below:







the torch itself







http://www.panix.com/~presence/torch.JPG







the mating surfaces of the tip







http://www.panix.com/~presence/tip-seat.JPG



Maybe try cleaning the mating surfaces with some fine steel wool. Check for daylight between the mating surfaces or mark the mating surfaces with a colored marker to see how they seal.

Water based only. NOTHING containing any oil or flamible materials

near oxygen.

No seals in danger of burning here. Any fuel content of markings from magic marker would probably be negligible, but I agree to keeping the mating surfaces clean.

On 4/14/2014 1:02 PM, Cydrome Leader wrote:
I finally dug out the $2 garage sale Craftsman (really Harris)
oxy-acetylene cutting torch. It came with a cutting head of unknown size
which I just cleaned out and #7 torch tip.

It passes the soapy leak test when pressurized, and the o-rings appear ok.

I've not used one of these before but have run into a problem.

I set the acetylene until the flame is not a smoky mess. Then I add oxygen
at the cutting attachment valve (It's wide open on the torch handle) then
I push the cutting lever and the flame gets really vicious. When let go of
the cutting lever, the thing goes BANG and the flame goes out.

What might be going on here? I've got a new set of torch side flashback
preventers to attach before I play with this more.

The welding forums go on about how this is backfire vs. backflash and that
the torch is leaking air or the O2 pressure is too low or something is
broken. It's all vague.

I had the O2 as about 10PSI at the regulator and the acetylene around 5.
Not sure if these are correct-ish.

Suggestions?

Leave acet at 4 for life unless cutting more than 1" thick. Min 20 O2
unless using extra small tips. For what you have in it, take it in, and
have it rebuilt, and be sure the rest of your life. An on fire fire
spewing torch isn't a fun think. DAMHIKT.

Steve