Cutting large pipe

I have a 3’ long, 3" diameter copper pipe that is 14gauge. I secured
it in my vice with a piece of wood inside surrounded by a towel to
help keep it from collapsing (although it would take quite a bit of
force to collapse this). The pipe was part of a steam pipe used in
an electric plant that was replaced.

I used a punch to create a few holes and tried with my hack saw to
saw through this. It scratched the surface literally but didn’t make
any progress. Without having to buy a special cutter for $150 to use
one or two times, is there something else I can use, maybe a special
blade for my circular saw, machine shop?

Wondering if anyone else has found an answer for cutting large
diameter pipe.

Regards,
Dinah

Have you tried to anneal the piece yet?

Hi Dinah,

3" diameter isn’t that big really, try 6" diameter 1/4" wall
thickness steel pipe, so a softer smaller diameter pipe shouldn’t be
an issue. FYI, I cut this pipe with a hack saw the first time, a
small angle grinder the second time, a monster angle grinder
(commonly called a wrist breaker) the third time, and a chop saw the
last time. The chop saw was the one I felt safest using.

Firstly, remove the wadding, that’s going to make your life a hell.
14 gauge copper wont collapse easily.

Buy a hacksaw blade designed to cut non-ferrous metals. They have
very large teeth so that the blade wont get clogged.

That’s if you want to cut by hand.

I would recommend alternatives :-

  1. If you have an angle grinder, or a friend may have one, a cutting
    disk will make short work of this job.

  2. A friend with a chop saw could be handy.

  3. If you don’t have friends with tools, and you don’t want to buy
    them. Go to a steel or metal store and ask them to cut the metal for
    you.

Regards Charles A.

find a machine shop with or rent a horizontal band saw.

Without having to buy a special cutter for $150 to use one or two
times, is there something else I can use, maybe a special blade for
my circular saw, machine shop? 

Hi, Dinah. Rent. Go to your local tool rental shop - Some Home
Depots have a rental department - and rent a large pipe cutter. Then
do all your cutting on one rental, obviously. I’d think maybe
$10-$20/day for something like that. Plus you’ll get perfect edges
every time…

Hi Dinah,

If I were you, I’d take the pipe to a plumbing shop & ask them to
cut it. Most plumbers have the tools & expertise to cut it…

Dave

Dinah,

After forever making crooked cuts with a hack saw or rather scary
adventures with a metal cutting table saw a 4" x 6" metal band saw
was acquired. A delightful machine even if only used rarely, I still
giggle watching it. Clamp in the stock (up to 4" x 6" and flip the
switch. Runs without attention although I stay in the room. Not much
noise, very accurate cuts and you don’t end up with one arm larger
than the other.

Saw, shipping and a good US blade was ~$350, more than your $150. A
local machine shop should have one if you only want a few cuts (bring
coffee, donuts and a smile when they aren’t busy). Otherwise buy the
best hacksaw blades you can find. There really is a big difference
between dollar store ones and premium US bi metal blades.

Recent jobs included large chunks of Al bar, accurate 45 degree
angles on 2" brass tube, and making thin wax slabs from a large
block.

jeffD
Demand Designs
Analog/Digital Modelling & Goldsmithing
http://www.gmavt.net/~jdemand

1) If you have an angle grinder, or a friend may have one, a
cutting disk will make short work of this job. 2) A friend with a
chop saw could be handy. 

Abrasive cutoff tools don’t work so well on non ferrous soft metals
like copper or aluminum, not that you can’t do it but it will be
much more difficult than cutting steel with one. A band saw is a much
better solution.

If you don't have friends with tools, and you don't want to buy
them. Go to a steel or metal store and ask them to cut the metal
for you.

possibly the best solution

James Binnion
James Binnion Metal Arts

If the tube was copper I might suggest a large wheel type tube
cutter as used by plumbers but this stuff seems altogether too tough
for that. Are you sure its copper or some alloy that looks like
copper? I have never encountered copper that resists cutting the way
you describe it. Perhaps it’s some form of bronze or cupro-nickel
alloy such as monel. I know monel has been used for boiler tubes.

You may need to try annealing it first. This seems like a big ask for
such a massive length of tube. Maybe an abrasive cutoff disk on an
angle grinder could do the trick. They are usually relatively
inexpensive. It will give you a rough finish on the cut though but
at least if you get it into workable size pieces for annealing.

Perhaps you need to buy a new hacksaw blade? It should certainly cut
a copper pipe, although it will take some time for one that big.

John
Indiana

Thank you to all of you great people who emailed me with
suggestions. I took a chance and took it up to a friend of mine who
is a farrier. He had a saw for cutting iron and steel in his
blacksmith shop-along with a gigantic old Buffalo Forge to die for.

http://startingboxdesignsco.blogspot.com/ photos of before and after
in first blog post

Kind regards,
Dinah

Abrasive cutoff tools don't work so well on non ferrous soft
metals like copper or aluminum 

In my research for fabbing an alum manifold I discovered they do
indeed make specialized aluminum cutting abrasive chop saw blades.
But one needs the chopsaw first. A decent one will exceed the $150.

I would advise against a circular saw on tubing, scary thought,
kickback and all!!!

But I’m wondering if the piece in question really is copper, the
hacksaw seemingly just about scratched it and who would use copper
for steamfitting??? I’m dubious.

In my research for fabbing an alum manifold I discovered they do
indeed make specialized aluminum cutting abrasive chop saw blades.
But one needs the chopsaw first. A decent one will exceed the
$150. 

Yes they do but most folks have the iron and steel blade and you get
results like the OP shows on her blog, horrible rough cuts and large
burs

James Binnion
James Binnion Metal Arts

It would used in low pressure hot water systems. Dinah did e-mail me
off line, I visited her site, nice work, and especially nice piece
of metal. She has a good pic of the original piece of pipe. All,
IMHO.

My friend, the farrier, has a chop saw and uses it for solid steel
and iron, and copper when necessary, since he makes corrective shoes
out of 1/4" thick steel, which is the thinnest he cuts with this,
some pieces are solid 4" diameter.

That’s what we used. We placed the tube on the table, the end of it
was on an adjustable stand to keep it level. It is copper, and the
pieces annealed easily. It was used in a plant in VA for a heating
system. They upgraded and disassembled the system and sold off the
scrap.

The pipe is 3/32" thick. I was able to drill for the rivet designs
on one bangle, and hammer into wood for the anticlast bangle, and
hammer and stamp. On the anticlast I had to anneal between each round
but did not consider this was anything other than copper, but maybe
it is. If it is something different, I would love to know what it is,
that would be fun.

Kind regards,
Dinah

I would highly caution any one using an abrasive cutoff wheel on any
power tool use a wheel specifically made for soft metals. Using a
wheel for steel on soft metal has the potential to load up in the
pores and explode. I have seen this happen first hand. I was a
designer in a fab shop. One of the men in the aluminum shop needed a
new wheel and could not find one.

He got one from the steel shop. It quickly loaded up and he pushed
harder on it. It heated up and exploded. A trip to the emergency
room was required to remove bits of wheel from various parts of his
body. So whether you beg, barrow, steal, rent or buy be sure it is the
right wheel.

As to saw blades there are ones made for soft metals. One made for
hard steel can load up. This can be brushed away and go at it again
but very frustrating and can break a blade. Be sure to use the right
tools and be safe.

Rick McC

Abrasive cutoff tools don't work so well on non ferrous soft
metals like copper or aluminum, not that you can't do it but it
will be much more difficult than cutting steel with one. A band saw
is a much better solution. 

That’s why you buy disks for non-ferrous metals. It’s the same as
you don’t cut non-ferrous metals with blades designed for ferrous
metals.

I didn’t think I had to spell that out, but it seems that I will
have to in the future.

A band saw is a better solution, or so I am lead to believe, but as
I don’t have one I only outlined methods I’ve used.

If you don’t have friends with tools, and you don’t want to buy
them. Go to a steel or metal store and ask them to cut the metal
for you.

possibly the best solution 

Funnily enough it works out to be the cheapest solution also.

Regards Charles A.

Perhaps it's some form of bronze or cupro-nickel alloy such as
monel. I know monel has been used for boiler tubes. 

Didn’t think of that, what if it’s a weird aluminium bronze, then
it’d be a royal pain :frowning:

Charles A.

Yes they do but most folks have the iron and steel blade and you
get results like the OP shows on her blog, horrible rough cuts and
large burs 

That’s why it’s important to have the right blades for the job.

Regards Charles A.

Using a wheel for steel on soft metal has the potential to load up
in the pores and explode. I have seen this happen first hand. Be
sure to use the right tools and be safe. 

You mean the wheel shattered.

Wheels shattering can happen if you don’t know what you’re doing.
Never pick up any power tool that you don’t know how to use. A lot of
people “think” that a large angle grinder is the same as a small
angle grinder. A large angle grinder needs respect, if the disk
jambs, a lot of nasty things can happen, the lease being that both
your wrist get broken.

Disk selection is very important as you have outlined. A bit of
research, and asking questions is always advised.

Regards Charles A.