Natural gas torch

Jewelry Discussion
1

Hi lovely Orchid people

I have been soldering for a long long time using butane and propane
table-top torches (the sort plumbers use with the disposable tanks)
I want to upgrade at last, and as I have natural gas almost to my
studio (in the basement of my home) it seems sensible to use it for
fuelling a torch.

I think I need oxygen (?) though ambient air would be more
convenient. Is a natural gas torch a special animal, or can I buy a
propane torch and use it with natural gas? Is the heat produced
sufficient for large and chunky cuff bracelet production, say if I
want to solder on bezels and other parts?

Any help and comments would be most appreciated.
Thanks, guys :slight_smile:
Janet

2

there are torches that can be used with city gas and ambient air, as
well as O2…depends on what you want. Don’t use that same hose used
for propane, etc. with other gasses. A butane torch will solder a
cufff bracelet and bezels just fine and you can even melt a small
amount of scrap with a bernzomatic/blazer/ hand held non-pencil style
torch. Smith’s ar too expensive- gentecs are cheaper. Hoke makes one
for use with city gas (orifices are a bit different) but they yuse
O2, there is a Purox that uses city gas and ambient air. as do a few
other manuf.'s. The plumber’s torch yuou are using isn’t a good habit
to get into - it’s too awkward for one thing. Bernzomatic makes a 50
dollar unit that uses disposable cannisters of fuel and O2 but they
are expensive- but you can melt anything with one of them and the
regulators are built in you can’t use different gasses though with
the same hoses, so just start with MAPP or Acetylene- other drawback:
the torch in question takes # oxy. tanks to 1 fuel gas. with the
butane it will accomplish everything you mention for far less outlay-
I always think you should have a back up torch in addition to
whatever the main one you have is- so that said, natural gas is
ideal. Don’t get sucked into having the always on pilot torch lighter
thing-y installed. I think they are dangerous and a waste not to
mention hazardous. open flame in a closed space= not good! Hard
lining the city gas into an ambient air set up is a great way to go,
however with the O2 “boost” you can do more than just solder when
you need to, say, cut steel for repairing a metal bench, etc. I think
your insurer would prefer the natural gas torch set up over tanks in
your space too. Some gas companies bawk at installing natural gas
lines for torches(i know you said they were existing) so see if any
plumber friend will do it for you, unless you are comfortable doing
it yourself. Ther was a thread a couple of years ago on Orchid about
this very subject and insurance. look for it in the archives. good
luck. rer

3

Hi Janet,

You will need to get the gas company to put on a different
regulator, as natural gas is pumped into a house at a low pressure,
something like 2 PSI.

We have guys that run back yard furnaces, they use natural gas (with
the special regulator), and forced air. Oxygen would make your torch
hotter, but with out the extra pressure you wont have much joy.

Regards Charles A.

4

Janet- We use natural gas in our shop/studio. It’s easy to plumb in
with black pipe, no boosters needed, and we use an oxygen bottle for
oxygen. We use a 1/4 inch copper that is soft/ lead soldered line for
the oxygen. We pipe to our benches where it’s hooked up to flexible
torch hoses. We also have home made pilot lights on each bench with
an individual cut-off valve so we don’t have to light it every time.

Plumbing is easy for metal smiths as long as you follow simple
safety rules and the proper pipe and connectors for each application.
No need to hire a $100.00 per hour plumber.

You will be pleased with the control you can get with gas and oxy.
We have cast up to 25 ozs of metal with our set up. Just check to see
that your torch will be suited for natural gas. Most are.

Have fun and make lots of jewelry.

Jo Haemer
timothywgreen.com

5

Hi Janet,

I had the good fortune to use natural gas torches with compressed air
for a while and they were great. They were large torches with a very
large flame, probably 12" or so. I suspect a fairly good size
compressor was necessary for these large torches, but with smaller
torches, perhaps one of the small portable compressors might work. I
was using them for annealing large pieces that I was raising into
vessels and some brazing of smaller 2 to 4 oz silver boxes. What I
liked about them was that, because of the cooler flame temperatures
(compared with acetylene) but larger flame area, it was much easier
to sneak up on the desired temperatures of the pieces and hold those
temps for a while. Also, being able to adjust the fuel/air mix with a
larger flame area meant that a large bushy, less oxidizing flame
could be used to lessen the chances of the dreaded stain in
sterling. If I had natural gas available I’d consider it. The only
drawback might be if one had difficulty in isolating the noise from
the compressor.

Cheers,
Dennis Fisher

6

If you want to do it safely you should install a natural gas
compressor to boost the pressure to the point where the NG will be
like any other torch fuel gas. Natural gas is supplied to your house
at about 1/2 psi otherwise listed as 7-8 inches of water pressure.
This is too low a pressure to use a flash arrestor which is the
safety device that prevents you driving a flame back down your gas
supply line by accident.

That said there are folks who have used NG straight out of the wall
for years with no problem but the local fire marshals and insurance
companies are typically not thrilled with that type of setup.

James Binnion
James Binnion Metal Arts

7

If you want to do it safely you should install a natural gas
compressor to boost the pressure to the point where the NG will be
like any other torch fuel gas. Natural gas is supplied to your house
at about 1/2 psi otherwise listed as 7-8 inches of water pressure.
This is too low a pressure to use a flash arrestor which is the
safety device that prevents you driving a flame back down your gas
supply line by accident.

That said there are folks who have used NG straight out of the wall
for years with no problem but the local fire marshals and insurance
companies are typically not thrilled with that type of setup.

James Binnion
James Binnion Metal Arts

8

Here in NY pretty much all the shops in the jewelry district run
natural gas and oxygen. Plenty of heat for everything except maybe
casting platinum. And only one bottle to worry about refilling.
You’ll also find the Hoke torch at most benches.

Elliot Nesterman

9

Janet, I can’t comment on natural gas, but I do large and chunky
cuff bracelets (in brass, copper, and nickel-silver) all the time
with my acetylene (no oxygen added) torch.

Judy Bjorkman

10

I use natural gas, but have chosen to use a gas booster (from G-tech,
the small ones are about $1500 US). The natural gas supplied by the
gas company is at such a low pressure that it can’t push through a
flashback arrestor safety valve. For me that was a worry and so the
price of the booster was worth it. The booster is basically an air
compressor for natural gas with an internal safety valve. The
additional flashback arrestor prevents the freak occurrence of
ignited, pressurized gas from going backwards, out your gas line and
causing damage or a fire. It’s not needed with your stove or water
heater because in that case you are not combining the natural gas
with pressurized oxygen. The benefit is that I can turn up the
pressure for casting with a torch. I know a lot of people don’t use
gas boosters. I wish they would, just for the sake of safety. I
believe boosters are required in the city of New York if you are
using natural gas.

Mark

11

First let me say that I represent G-TEC Natural Gas Systems - we
build small natural gas Torch Boosters that are designed for jewelry
torches. the commercial will come at the end of this message.

Anytime a torch uses fuel gas and oxygen OSHA, local fire codes and
common sense require a flashback arrestor on the torch. Many jewelers
don’t use flashback arrestors saying, “I’ve been doing this for XX
years and I’ve never had a problem” - many people do dangerous things
and live to tell the tale. But some have accidents and you don’t want
it to be you.

12

I’ve had this setup in my basement studio for years and have never
been disappointed or had a problem with my G-Tec unit. I use the
Smith Little torch and purchased an a

13

Thanks so much for everyone who contributed their comments to my
query on natural gas torches. You’ve all been extremely helpful, and
helped me to come to a decision on it all. Thanks again people!

Janet

14

First let me say that I represent G-TEC Natural Gas Systems - we
build small natural gas Torch Boosters that are designed for jewelry
torches. the commercial will come at the end of this message.

Anytime a torch uses fuel gas and oxygen OSHA, local fire codes and
common sense require a flashback arrestor on the torch. Many jewelers
don’t use flashback arrestors saying, “I’ve been doing this for XX
years and I’ve never had a problem” - many people do dangerous things
and live to tell the tale. But some have accidents and you don’t want
it to be you.

As James Binnon noted natural gas pressure in most places is < 1 psi
and all UL Listed flashback arrestors need at least 1 psi pressure
for gas to flow through them, otherwise they block gas flow and you
can’t light the torch.

The purpose of the flashback arrestor is, in the case of a
flashback, to extinguish the fire in the torch hose. Many jewelers
have checkvalves and believe they are protected but all a checkvalve
does is prevent high pressure gas from flowing in the wrong direction

  • if you have a flashback the 5,000F flame will melt the checkvalve!

Jewelers in NYC who want to use city natural gas are required to
have a pressure booster to raise pressure enough so that flashback
arrestors can be used effectively. There is more about
what is required, as well as explanations of flashbacks, flashback
arrestors and checkvalves on our website here:
http://www.ganoksin.com/gnkurl/ep8035

Another consideration is the right working gas pressure for a torch.
People using acetylene and propane for bench torches normally set
pressure between 3-8 psi yet jewelers use city natural gas at 1/4
psi. I don’t think there are any jewelers setting their acetylene or
propane torches at 1/4 psi - the flame would pretty weak.

We’ve found that jewelers who have installed our Torch Boosters much
prefer the flame on their torches when they can set gas pressure
higher than what the utility offers. Our customers include everyone
from Tiffany & Co., Jared, The Galleria of Jewelry, colleges and
universities, independent retailers and individuals in home studios.
They have found that with higher pressure natural gas they get the
full performance that their torch is designed to give - they are
surprised and pleased.

An earlier comment mentioned the noise of a natural gas compressor
but our units are pretty quiet - you can see and hear one on a
YouTube video if you Google “TB-15/30 Video” and look for the one
that says “by GTECNGS”. It will also show how they are installed and
work.

If you are going to be at the MJSA Expo in NYC next week I will be
in the Gesswein exhibit - please stop by and I will answer any
questions you have.

I’ll also be happy to tell you how G-TEC Torch Boosters are used in
making the Super Bowl’s Vince Lombardi trophy, baseball’s
Commissioner’s Trophy for the World Series winner, and others!

Ed Howard
Sales/Marketing Manager
G-TEC Natural Gas Systems

15 
I think I need oxygen (?) though ambient air would be more
convenient. Is a natural gas torch a special animal, or can I buy
a propane torch and use it with natural gas? Is the heat produced
sufficient for large and chunky cuff bracelet production, say if I
want to solder on bezels and other parts?

Janet - I’ve used natural gas for 20 years. Like you, I had the
connection in the house and I had a proper plumber add a connection
for me. I had recently taken classes at our community college and
they used natural gas with compressed air. Our air compressor was
really noisy so I’ve always used compressed oxygen. Four years ago I
got fed up with the very low residential pressure of ng and installed
a natural gas concentrator - a G-Tec unit. I don’t like the fan noise
of the concentrator, but I really like everything else. I can run two
torches - when teaching - and have pressure to spare.

My torch of choice for residential pressure is a Meco with
ventilated tips.

The regular tips are ok, but the ventilated ones really put out
heat. The flame produced was designed for glass workers so there is a
warm surround on a hot center flame. The tips are not easy to find,
but worth the search - I’m still looking for a new #3 ventilated tip.
The Meco is particularly suited for low pressure gas because of some
internal design - but I don’t remember the particulars.

To answer your questions - you do need either compressed air or
compressed oxygen with natural gas. Because of its low pressure, you
need a torch rated for ng. And in line with the current thread about
medical oxygen concentrators, I too found the noise and the variable
pressure annoying and sent the unit back. A big tank of compressed
oxy lasts forever, or almost forever.

Our school set up with ng and compressed air was more than
sufficient to solder or anneal vessels. It would work just fine for
heavy silver jewelry.

Just get the right torch - for that mixture, we used a Hoke torch.

Judy Hoch