How to bend
Metal Pipe
TFS: Tube Bending Basics 1 - What You Need to Know
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81,000 welcome to another episode of the
fabricator series with yours truly
so strut tower braces bash bars roll
cages roll bars and miscellaneous pieces
of to all have one thing in common when
you get to fabricating all of these
they're all going to need to be bent so
that's we're gonna go over right now a
2-bit in basics
[Music]
a lot of people tend to get confused -
versus pipe now both of them are around
in shape both of them having wall
thicknesses they're identifying size and
both of them have the same number to
identify their actual size or reference
so in this case we have inch and they
have two then we have inch and a half
pipe let's start with the tube tube is
measured on the outside diameter or the
actual size that it is and it also has
an identifying wall thickness was the
actual measurement that it measures out
to so in this case this is an inch and a
half OD with a 120 wall which means it's
an eighth of an inch thick pipe on the
other hand this is based on measured on
its inside or nominal inside diameter so
the outside of this is about 1.9 inches
round and the wall thickness is referred
to as a schedule so in this case its
inch and a half scheduled for T now
since this is pipe and it's measured on
the inside diameter that means I can
actually take this ancient have tubes
live inside of the inch and a half pipe
both of them are inch and a half that's
what the rare or referenced as but both
of them don't actually measure to inch
and a half only tube does and only two
is used for making roll cages now that
we've got the differences in materials
figured out let's talk about the bender
this is very very popular to do when
trying to save some money in bending all
of your materials there are two benders
and there are pipe benders now one is
really not supposed to be used with the
other one for a couple of reasons let's
just go over real quick the tubing
bender when you stick your tube into the
bender itself and you lock it down the
tube will actually be pulled or drawn
around this bond of this die itself go
through here and I'll actually pulled
bent around it now most tubing benders
will actually sell pipe size dies and
you can do the exact same thing with but
one way to identify the pipe is by
looking at how it's set up in which case
that is usually set up with a hydraulic
press and a little bending shoe right in
the middle of it that presses up against
the center of the pipe itself and what
that will do is eventually form and kind
of wrap it around there now while that
does work for pipe as a material it's
actually terrible for
there are millions of hacks and tweaks
and ways to try and get tube to work in
a pipe vendor but take it from me save
yourself the time and hassle by a tubing
bender if you plan to bend tubing all
righty so three words that people
typically get confused with regarding
bending dies
center line radius Center meaning the
center of something line meaning in
reference point and radius meaning half
of a circle which if you pay attention
in geometry class you know that the full
circle is diameter half the circle is
radius so in this case we have our diet
and each die has its own size that it
bends this one is Eames and 1/2 this one
is one-inch each one also has its listed
centreline radius this inch and a half
die is a four and a half inch radius for
centerline radius this one-inch die is a
3-inch centerline radius what does all
of that mean well let's actually break
this one down centers meaning a
reference point in this case it's the
center of the tube itself so this
section here would be the center of it
this section also the center of it this
section any point at least within this
tube or at least within the points where
it actually starts at the bend itself to
create that radius is the point where
it's going to be reference so anywhere
in here all of this is your centerline
of course my hand a little squiggly on
this one but you get the idea
line meaning the actual point of
reference were measured at so again when
I traced around so a centerline which is
this area and radius meaning half of the
circle so we'll show you want to die
here every die obviously centered since
this is a semicircle or it is round we
have a center point which is right here
in the middle of it and to the center of
the actual tube itself where the bend is
that distance between the center point
here and the center point of the tube is
your centerline radius okay so the
larger the number you have for the
centerline radius the more gracious or
more gradual your bend is going to be
the smaller the number the tighter the
menu
do you you're gonna end up with okay so
this is where a lot of people ask me and
I'll tell you every single time the same
way what size died do I get when it
comes to bending stuff like cages or
bash bars or whatever the case is now
the answer that one really is entirely
up to you theoretically you're supposed
to measure out what exactly you need for
each one now say roll cages for instance
you're not allowed to have too tight of
a bend and of course you don't want to
have to gradual of a bend because you
know there are some areas inside of like
a chassis or the body of a car where you
know the tube might not fit if it's you
know a th centerline radius that'd be
kind of ridiculous so most rules will
specify the general rule of thumb and a
general rule of thumb for identifying a
centerline radius is diameter times
three so no matter what the bend radius
is or whatever the rulebook specifies
they almost always follow that one so at
bare minimum when you get a die and you
intend to bed roll cages for example out
of that specific size diameter times
three is a safe centerline radius to
purchase now if you're doing the math
inside of your head make sure that you
get your numbers right so if everything
is based off of the center you've got to
know that if you've been less than 180
like this piece you'll know that the
center line radius is four and a half
inches not only leads from Center to
Center which means from Center to Center
you have nine inches wide now if you go
all the way to the outside of each bed
you'll know you have a ten a half inch
wide Bend total getting the inside of
that Bend will be seven and a half
inches so just make sure that you do
your math correctly and know that when
you get a half-inch centerline radius
that you'll know your total width the
total inside measurements
[Music]
a little bit about the dies with
centerline radius let's actually break
down the nomenclature of the bender
itself this is my bender it is a G B
squared model 3 a lot of people will ask
me how I like it and in all honesty I'm
actually you could probably consider
this a step down to what I used to use
which was the tube shark and honestly I
believe in this mechanical bender here
or a manual bender it's I have a lot
more control out of all of my bends and
actually I really prefer it over the you
know big heavy expensive models so this
isn't actually a great bender and a lot
of people would say how would you rate
this for let's say beginner to advanced
is is exceptional it actually really it
has done everything for roll cages the
tube chassis and everything in between I
love it so this section right here the
main section right here is your frame
link this is essentially what holds
everything to at the stand holds your
ratcheting assembly your ratchet arm all
of it goes on to the framework itself
all right next up we have the drive link
in this section here when we plant the
dyad and we swing this along here this
is what's actually going to move the die
around and make our bend then have our
die this one being my inch-and-a-half
die with a four and a half inch Center
no one reads pin goes in the middle
holds everything together now notice
that these two swing independently of
each other so we have our drive pin now
each die has its own contour its own
profile cut into it now the idea behind
this is it will hold the walls together
and not allow the outside of it to crush
inward and not course let the inside
kink now every manufacturer will have
their own die profile that they cut of
course you have to have the follower now
the follower is for the outside of the
tube to keep that same profile cut into
it when we set the die in here or the
follower in here along with its pin you
now have the ability to throw a tube
inside of there and start bending it
gravel am I gonna have to
with our TBA also has a pin and we'll
lock it in there normally that would be
in there very tight take this and you'll
start bending little by little and go
all the way around now if you've watched
any of my other videos where I reference
a lot of bugs to bending or I do a lot
of tube bending you'll see me do two
things and when I before I start my Bend
one of them is setting my dial to zero
but that is after I set the preload now
you notice that in here we have a little
bit of looseness okay before the tube
actually starts to contact the die and
the follower that's preload when you're
set to zero and it's ready to start its
Bend immediately when that happens you
set your die right on your zero mark and
then you make your bed of course this
follows around the pin will follow
around and you eventually stop wherever
your Bend angle is that you need to make
[Music]
now there was one more question that I
receive a lot from viewers and whatnot
when they write in and ask about bending
so here it is you'll see a lot of
manufacturers JT squared in particular
also does this they sell dies in 90
degrees and 180 degrees which one should
you buy Wow that choice is entirely up
to you because they are two different
prices and of course 180 degree is
normally more expensive than the 90
degree now how often do you actually end
more than 90 degrees well if you're in
the off-road industry and whatnot like I
build a lot of parts for those and they
tell you like shock hoops and stuff like
that they start around 120 degrees and
go up to 180 so it really all depends on
if you're planning on doing that some
model benders for example they're a
little bit difficult to make a 180
degrees worth of a bend
I agree doc because you have to make
them back-to-back and made that
transition in between there's almost
always something a little bit of a gap
in between there because it's very very
hard to set that up now which one should
you buy what that choice is entirely up
to you but if you ask me personally I
always say go ahead and go with the
hundred eighty degree because you just
don't know when you're going to need to
bend more than 90 degrees now we get to
the fun part this is before we can
actually start bending anything there
are two things that you need to know or
at least one that you really need to
know on the other one you should always
have on hand because there is an easy
method dependent the first thing you
need to know is your cost of material
per Bend
or how much material it takes you to
make let's say a 90 degree bed or
anything in between including 180
degrees any Bend that you make on it you
need to know how much material it
actually uses throughout that bed in any
one of these beds or any Bend that you
do and you need to do this for every
single sized die that you have it's one
of those things that you have to have
them out of your head or at least know
before you start calculating all my pins
the second thing you need to do is
create a cheater and we'll go over the
cheater and how that works a little bit
later but I'm definitely to show you how
to make one of those right now so let's
start with our cost of materials to
calculate our actual cost of materials
we're gonna create what we call a
bending gauge and what we're basically
going to do is take a piece of tubing of
the size that you're going to bend the
wall sizes are relevant and we're gonna
mark it you have one inch increments on
our actual tube here and then we're
gonna throw it in the bender toss a
ninety on it and then we'll actually
figure out how much material it takes to
do ninety degrees and we'll measure out
all of our degrees subsequently in ten
degree increments as we go along
so first we'll need to start out our
star placement or actually calculate
where our start of our Bend is actually
going to be so we need to have some
material away from the die that will
actually strap and hold to the actual
die itself with the with the strap or
the or the tube stake you know whichever
one you want to call it s so we're gonna
start at four inches now I'm just going
to use the actual seam of the tube here
as it as a reference so it's gonna be
pointed upward inside of the bender
there which will actually be our center
line on the center line radius itself
and we'll just
we'll just start making some increments
here at one inch so let's see we'll go
up to up to twelve let's say 13 inches
well that's what we're run-up to so all
of these kind of straighten and thicken
them up a little bit
these are all of our one-inch reference
points then we're gonna load up into our
vendor here and this being the start of
our Bend just make a be there
now we'll go toss that in the bender
all right we'll load this up and make
sure that our seam here is when I said
was gonna identify as our center line is
actually with or along the center line
of the die itself and the start of our
bend at the die is where I'm going to
line it up that's basically point zero
our stay crank this down down here
because you don't want to slip as you're
bending it if you slip you'll cause
kinks so if you're not sure about how
much force you want to apply to this
throw a dummy tube in there and crank
that sucker down what you want is nice
and snug so it doesn't slip and you
definitely you don't want a too snug to
where it's gonna collapse the wall or
leave this massive indentation in your -
so once you figure out where that is -
just get it nice and snug in there we're
gonna pre-loved and set our dial on zero
okay every 10 degrees I'm gonna make
another mark on this too
there's one all right so we're locked
right on ten degrees now we're gonna
make a mark right at the follower on the
tube itself make sure that it's nice and
dark and that you can actually see it
now we're gonna set this up again and go
to 20 degrees there's 20 so you make
another mark at the follower we're gonna
keep on going every 10 degrees and make
another look all the way up until we get
to 90
there we go now we'll take this out and
calculate okay so we have out and what I
did is created a starting point this is
where the impression of the actual
follower is in the tube there and that's
when we are basically ground zero for
all of our angles now for our
measurements of cost of material you can
see all of our black lines still are
still on the tube and of course they're
on the centerline where they need to be
and these we can extend up into the
center line if we actually need to so
let's start with the cost of material
here take a look at your Bend and if you
hold it in the right light you could
probably see it there is a shiny spot
where the actual Bend itself begins on
the tube you'll see a little impression
where the where the dye left on the tube
same thing for its termination where it
stopped which is about right here now
you calculate or add up what's in the
middle one two three four five six seven
and that right there is about a quarter
of an inch roughly in between okay so
seven and a quarter inches that's how
much material it actually takes when
it's in the dye now notice before that I
use my bending reference or the
beginning of the dye as the start of my
Bend in everything that I do in which
case you'll add the extra three quarters
of an inch to this one which is this far
away here and you get eight inches total
now I typically in all of my bends I
usually add the tolerance into it now if
you watch that say the roll cage video
for example you'll notice that I had a
bending tolerance with everything and
I'll say that my die cost me about eight
and a half inches so in all actuality
you just need to know that the total
from the start of the bend to the
termination of the bend in the actual
die the impression that the leaves is
seven and a quarter inches on this die
now if I add in my additional to the
point of how much material I need from
the start of the die in the bender
itself then I know I need eight inches
and then I'll add my tolerance into that
later now you can check out some of the
other videos in the list and whatnot in
the links that I put up here to see a
whole lot of that visual
or that in action and then you might
have a pretty good understanding of how
it works then now what are all of these
little ticks for on all of these angles
that we created here now that's for
measuring each individual angle and how
much material it costs you to bend it so
we already know how much material it
takes to bend 90 degrees how about all
these other ones which we mark these in
10 20 30 40 50 and so on all the way up
to 90 so how do we calculate all of
those well look carefully here the start
of our Bend which I already made the
reference on this one is at the point of
zero here how much material it takes in
that Bend itself so what you basically
need to do is take a measurement here
you'll start at the let's say a 10
degree bend to the actual start of in
itself here looks like three-quarters of
an inch away so 10 degrees takes three
quarters of an inch 20 degrees we'll say
one yeah it's a little little tick over
there so say it's about one two and a
quarter inches worth of material that it
takes and then you go over here to 30
degrees take so just under sets about
know one two and a half-ish and then you
just keep on going so on and so on and
so forth so now you can check out some
of my other videos and I'll put the
links up in here and of course down in
the description if this still doesn't
make sense to you I do reference and use
this a lot so you can absolutely follow
along there and if you're still not sure
on top of that drop me a question I'll
do my best to actually describe all of
this in reference to the video here and
all the rest of that good stuff so if
you have a question drop me a you know
comments email and either the social
media outlets of course you can post up
there and I'll do my best to get back to
you so this is essentially your bending
gauge now what I usually do is kind of
set this aside and put it into a pile
along with you know the cheater and all
the other ones I have dozens of these so
if I ever need to go back and reference
if I don't remember for example how much
material I need per angle then you know
there it is right there I can always go
back and check this out so that's how
you make your bending gauge
[Music]
now we're gonna move on to making the
cheater you know what is a cheater well
here's the best way I can describe the
cheater
it is a been in which case this is 90
degrees and I use 90 degrees for all of
my cheaters unless I need something
specific which sometimes I'll make you
know I'll let make like a 70 degree
cheater or whatever the case is so it
basically is is the actual Bend that
you're using with the dye and tube that
you plan to use okay and it has your
reference cut into it the reference is
the point where you will start and
measure all of your bends from in which
case my beginning reference is always
referenced at the beginning of the dye
so like see on this one for example the
impression left on the tube is a little
bit distance right there you can
actually measure this out or whatever
the case is from the beginning of the
dye so just as we placed earlier when we
made the bending gauge the inside of the
dye at the start of the dye the same
thing goes with the cheater you always
want your reference wherever that is it
can be it can be anywhere as long as you
use the exact same reference throughout
the entire process of all of your
bending and measuring and whatnot so
this is a cheater already made of course
I can tell you how to do that or I can
show you take any length of tube this
one is let's see 17 inches long which
that's fantastic we already know that we
only need eight inches in between and
we're gonna start the beginning of our
Bend now let's say for long we'll go
four inches four inches is a decent
start of a band for a cheater this our
starting point we'll label that Bend go
toss it in the bedroom
just like before the start of our bend
or the start of the die is the beginning
of our been release that's the one that
I'd like to reference can you use
another starting location or a new
reference location yes you can use any
one that you are familiar with or
comfortable and using you can use the
beginning of the follower you can even
use the the tube stay if you want now
it's important that you identify and
know and repeatedly use the same
reference as the beginning of your bed
which every single one of my dies I
always start
the beginning of the dye as my reference
you can again you can use the stay you
can use the end of the actual stay block
itself you can use anything that's going
to be a repeat and reference it doesn't
really matter what it is but it is very
very important that you always and I
really mean always use the exact same
reference if you change reference in the
middle of a project let's say you're
building a a main hoop for a roll cage
and half of it is used as the starting
dye reference here and the other half is
used with the follower you're not going
to be able to bend it and and maintain
that kind of consistency inside of your
build so again whatever it is that you
intend to use as your reference make
sure that it's the same throughout
everything and if you choose to use two
different references you need to bend
two different cheaters okay so after you
have it locked in here crank it down
dial on zero preload a set let's go to
ninety degrees let's just continue this
line all the way around to make it as
straight as possible of course you
watched my other videos you'll see that
I actually insert the tape measure for
the end of it into the bend itself so I
can get an accurate measure so your cut
needs to be wide enough actually hooking
inside of there in which case I usually
just use the chop saw to slice down on
this
[Applause]
now of course I did actually rotate the
tube so I can get a much more broad cut
around the tube in the areas where I'll
likely be measuring so I'm going to do
is set this up one more time here I'm
gonna try and set the tube up where it's
exactly where I was before of course you
want to make sure that it stays exactly
in line with the other kind of you just
made now those insides and whatnot we
can actually go on there chase them out
with a file if you want but now you have
a means of measuring where the start of
your bend is going to go versus where it
actually sits on a vehicle or a chassis
or the project and what you are bending
so let's get to the bending
you
