okay then joe so another piece of conduit in your hand what are you up to today yeah i've
put the calculator down again and looking at bending some conduit so this is exciting stuff
we saw in a previous video Gary we looked at how to get a really accurate bend into a piece of
conduit from the end of the conduit to the back of the conduit but what i want to do in this video is
i want to have a look at how we now put a second bend into an already bent piece of conduit and how
to get that bend perfectly accurately in place so that it drops neatly into another accessory
because in this case we've got two fixed points somewhere it's not as if we could start maybe
moving machineries or trunking because we've been conduit wrong absolutely not why don't
we just put a coupler in the centre here again it doesn't look quite as nice again that's an option
but it's going to take a lot longer isn't it to cut it file it ream it thread the ends clean the
ends if we can just get the bend in the right place first time we've saved ourselves an awful
lot of work there and this technique is often called on-site back of bend to back of bend yep
and that's for reasons that we'll we'll talk about as we start doing our measurement because actually
we'll measure from centre to centre that's the traditional way of measuring but then we need
to just tweak that measurement so that we can then get like you say the back of bend to back of bend
and we'll see why that's so critical i think it's important let's bring the camera in and see how
you're going to measure this up before we actually take over the conduit bending machine Joe let's
do it okay then Joe so brought the camera in and you're going to show us this measurement between
is it the centre of the box the centre of the box that's exactly right so we're going
to first of all measure from the centre of this spout to the centre of this spout and again the
easiest way to do that is just put the end of your tape measure in the centre of one end and
then measure to the centre of the other end and again if you're struggling to find the centre
it's just sort of the furthest back bit of the curve so wherever the back of the curve touches
your tape measure that's the value so we've got these mounted at 500 millimetres between the two
so that is our centre to centre measurement but when we start putting the bend in
using the technique that i'm going to show you you need to know what the measurement is
from the back of the bend so the back of this piece of conduit to the back of this
piece of conduit so we know that the conduit that we're installing is 20 millimetres in diameter
so we need to add 10 millimetres to get us from the centre to the back of that spout and 10
millimetres to get us from the centre to the back of that spout so 500 mm plus 20 mm becomes 520
millimetres and that's the critical measurement that we want for this bend thank you Joe
so joe you've moved the conduit back into a bay now what's the next stage so what we're going to
do now is we're going to get the measurement put on here of where we need to get the back of the
bend to so again scrap piece of conduit lined up against the edge that we're measuring off so bear
in mind the front of this edge lines up with the back of this edge so they're effectively
the same datum so what i'm going to do is just put my tape measure against that face and then measure
here the value that we spoke about which was 520 millimetres and just put that mark on there so
that there is 520 millimetres and that represents where we want the back of the bend to be so that's
going to bend down like so and that's what our piece of tube should look like after we've bent it
okay thank you so we've measured marked up on the floor Joe the conduit and you've taken it
back over the conduit bending machine so what are you going to do now for me so what we're going to
do now is we're going to put the second bend into our conduit just make sure that we get the conduit
into the bending machine in the correct way this is the back edge that we measured off so that's
our reference edge so we've put that end into the stop and then this is the end that we're going to
bend down the mark that we put is here so you can see that's where the back of the bend wants to be
so now it's a matter of getting the conduit lined up properly so what we're going to do
is pop our scrap piece of tube into the former and this resembles where the back edge of the conduit
will be after it's bent and then if we use our combi square to get that so that the two pieces of
conduit are square to each other and then what i'm going to do is make sure that my mark that i made
lines up properly with the back edge of my scrap piece of conduit so this piece of conduit is at
90 degrees to this piece of conduit and that mark is now lined up with the back edge of this piece
of conduit now i'm almost ready to bend but what i also need to do is make sure that the
end down there is actually vertical if this is a long way out like that then it's going to bend
not square however if i just get that so that it lines up with the former and what you're trying
to do is make sure that the end of the conduit is vertical as the former is vertical you're trying
to get those two pieces to line up with each other then it should be ready to bend so now we can put
our second bend in thank you Joe so then Joe you happy and ready to bend absolutely i've got my
vertical piece of conduit lined up with the former i've got the back of ben mark in the right place
so now we're ready to put our second 90 degree bend in so we'll do that now
and we're aiming to get that down to 90 degrees
and i always tend to under-bend it the first time so we'll get that in to there
and that looks somewhere close so we'll take this out of the former and we'll
measure it up and we'll see if we've managed to do this correctly so then Joe we're back
on to the floor now and you're just going to confirm to me that we're in 90 degrees
uh yeah so we'll see if this is at 90. so we've got our piece of conduit as a datum we've got a
combination square we'll slide that up and you can see that that is now at 90 degrees so we're happy
that we've got our two bends in correctly we just want to illustrate one more point one more thing
we can check before we offer this up to the wall so you've taken me over now to the bench show so
what are you going to illustrate this time so just to illustrate one more point when we were putting
this into the conduit bending machine we made sure that we got this end lined up vertically with the
conduit former and the reason for that is that we want to make sure that this and this are parallel
to each other in this direction so a good way of checking that you've got that right after you've
bent it is put it on a very flat surface as flat as you can get and then just push down on opposite
corners if it rocks backwards and forwards then those two arms are not parallel with each other
if however like this there is no rocking motion when you press on opposite corners it means that
that and that are perfectly parallel with each other in that plane okay then Joe so moment of
truth yeah we're going to see if our measurements and our bending have been accurate enough to get
this installed correctly so obviously what we'd now do is cut these both to length we'd thread
the ends of those and then we'd be able to install it but what i'm going to do is just rest that on
there for now okay and if we keep the top of that nice and horizontal what we should find
yes that lines up absolutely beautifully with the centre of that so by using that back of bend
to back of bend method we've managed to get the centre to the centre of those two boxes absolutely
spot on and it saved the need to cut the conduit make two separate bends and join it together using
a coupler probably it would have been better if we were using say adaptable boxes where we could
perhaps put couples on but we're just trying to demonstrate the point between two fixed places
i believe that this technique or a modification this technique might be one that will be needed
at AM2S and i'm going to challenge you for a third video okay where we'll go from a fixed
point up and onto a ceiling yeah and then we'll kick it either to the left or to the right okay
right so we'll be using the same principle of backup and tobacco bend but these two legs won't
be going in the same direction this one will come out that way effectively it will right okay yeah
that's great yeah we can do that okay it makes a third video so for this one joe i think we're
over and done with should we end it yeah let's do it we hope this video has been some help