My last video on Rollation has been very popular,
and over a hundred people have commented, saying they'd like to see some more
development of this process - making transitions between round,
rectangular, and oval shapes. So, this time we're going to get
into working with rectangular shapes. I'm going to make a transition
between two rectangles, and I'm going to rotate one 90 degrees, space them a certain distance apart,
and then rather than have them centered, I'm going to offset it so that this
one corner on both rectangles lines up. So I'll get a block of wood to space
these the right distance apart. I've assembled all the pieces for the form, and I've used two screws on each side to
make sure these rectangles can't move. So let's go through the Rollation process. We'll start with the form right here, and make
lines all around the perimeter with a pencil. I'm going to make a little
mark right at each corner. Then I'll roll this to the next position. Then roll it to the next position. And roll it one last time to the final position. So the next step is I want to draw lines
that show where the bends need to go. And now I'll cut the pattern out. So here's our pattern, and
just for a sanity check, let's bend this pattern on the
lines and make sure the edges meet. And everything looks just fine, so I'm going
to lay this pattern on a sheet of metal, mark around the edge, cut on the lines,
and then we'll do the forming on the blank. The material I'm using is 3003 H-14 aluminum. That's a very soft alloy and the thickness is 50
thousandths of an inch, or about 1.3 millimeters. I buy this material with a plastic
film on one side to protect the finish, so this is the good side. This is the outside, and when made my pattern,
my marks were made on the inside of the pattern, so I've transferred those marks to the
other side, and we'll do the layout. I'll make sure it's fitting tight
against the two straight edges on this. I'll use a felt tip marker
to mark around the edge. I also need to mark the bend lines on this so
I'll put little marks at the end of each bend. And then with the straightedge, I'll
continue those lines onto the white plastic. So I'll cut this blank out
and then we'll make the bends. There are special machines made for bending metal.
Press brakes and leaf brakes are the most common, but if you don't have such a machine, I'll
show you a way that you can do work like this. I'm going to make a test bend on a scrap piece
of metal. I've got two pieces of steel clamped together with a space between them just
about the same as the material thickness. And this is cold rolled steel bar,
which has a nice sharp edge on it. So I'm going to align my bend line
with the edge of the steel bar, and then put a clamp on the
bars to squeeze them together. Then I'll take a block of wood put it on
the metal and tap that down with a hammer. So let's take this out and
I'll show you how it looks. So it's made a fairly decent bend.
The bar has a 90-degree angle on it, and of course the metal springs back a
little bit after we force it against the bar. So if I measure the angle that it has, it's about an 85 degree angle, so the
metal springs back about five degrees. So we can make this work better by
sanding a slight angle on the bottom bar. So we bend it to 95 degrees and then when it springs back five
degrees it'll be pretty close to 90. And we'll check this with a protractor, and that's just about perfect. So I've reassembled the bending fixture
with that chamfered bar on the bottom. I'm going to align this piece so the bend
line is right on the edge of the bars. That looks good right there. We'll put a
clamp into place to hold everything tight. And I'll work that down by
hammering against the wooden block. Let's take a look. That looks pretty good. So this is set to 90-degrees, we've
actually gone just a little bit past 90. But it's easier to unbend metal than it is
to bend it so I'll take some of that out. And we've got just about a perfect 90-degree bend. So let's set up for the next bend. We align
the bend line with the edge of the bar, put our clamp into place. Cushion it with the wooden block. I just realized my part is hitting the
clamp, so I'll need to reverse the clamp and we'll continue hammering. So far so good, and one more bend to go. So let's take a look. So there's our part. It takes just light pressure to bring these
corners together, so this end looks good. And this end looks good, so now
we can tack weld this together. A lot of people asked about
machine setup for aluminum. The first step is I need alternating
current, so let's switch to AC. The formula for the heat is it takes 1 amp for
every thousandth of an inch of material thickness, so for the 50 thousandths material I'm welding, I couldn't make a puddle unless the
machine was putting out 50 amps, but I like to set the machine hotter than that. I'm going to go up to 75, and then with the foot pedal I can modulate
how much heat actually goes into the work. So when I ride the foot pedal at about two-thirds
throttle, 50 amps is going into the work, and that way I know I've always got
extra heat available should I need it. I like to set the flow meter to about 16
to 18 cubic feet per hour for aluminum. The material is carefully aligned, and clamped
up tight against the square aluminum bar, so I'm going to put a tack weld on the far end. I'll put another tack near the center. And now I can weld the entire seam. So let's unclamp this and take a look. So there's our finished weld. So here's our rotated and
offset rectangular transition,. And I think it actually came out pretty well, especially since we did the
bending with a homemade tool. So I had to make something like this once a
few years ago. It was actually a transition for a rain gutter connected to a downspout,
and they were at right angles to each other, so I had to make a transition just like this, except it needed a flange on
both the top and the bottom. Let's say we want to add a one inch flange
at the top and bottom of this transition. We can start by using the
pattern we made previously. I'll just tape this down, and then I'll trace
around the edge of this with a felt tip marker. And it's important to mark the bends on this. Okay, we'll peel the pattern off. And I'll use a straightedge to extend these lines. So this strip of metal is one inch wide. I'll use
this as a guide to add extensions to this pattern. So I'll cut this out now. I'll make a bend on each of these lines. And I'll fold that bend over double. Now I'll use a piece of tape
to hold the edges together. So to bend flanges here, so
these edges will be parallel, I'm going to have to make cuts in these corners. So now we'll make bends on these lines. So the thing I want to point out to you is that if we make the bends this way, there's always
going to be a notch in some of these corners. And yes, we could fill that
notch by welding a piece into it, but there's a better way to do this. A part like this is really
better to make in two pieces, because we can position the joints in such a way
that these corners will not need to be filled in. And the best place to put the welds
is down this corner, and this corner. So let me cut this apart and
I'll show you what I mean. So this is the simplest of the two parts. It's just an angle and these
flanged areas don't need to be bent. They'll just be a continuation of the
plane formed by this side of the part, so this one is very simple. This is slightly more complex, because this gets bent this way, this gets
bent in, and this gets bent out. But we won't have too much trouble doing that, and you can see that if I make a cut right on this
edge, that will fill in the missing triangle here. That's the same on both sides. So now we'll cut out two pieces
of metal from our new patterns. So the blank is cut, and ready to form. It's very difficult to maintain close tolerances
with a simple bending fixture like this, so I've made my part a little
bit wider than it needs to be. I've added about two material
thicknesses on each side, and you'll see how I use that
little extra metal in the next step. So I'm going to align the bending line
on the part with the edge of the fixture, and I have to be careful that
this end of my fixture comes right to the end of the notch on our
part, and I'll clamp this into place. Then I'll get my wood block into place, and again, this corner of the block has to
miss this small triangle here. And we'll tap this down. So there's our bend. Looks like it came out great! So now I need to bend these flanges. So I'll put this into place, slide it
right up to the line on the fixture. And I can probably bend this one by
hand. I just need to lift up on the part. That looks pretty good. Let's bend this one next. Now we'll bend the small tabs. And again, I can bend this just by hand. So there's our first part. So here's the blank for the second part, and I've cut this so it has the precise
height needed to match the first part we bent. So the height is correct, and just like with the first part, I've
added a little extra material on both sides, and I haven't bothered to notch out the corners
because we'll do that as a second operation. So let me get this clamped into place in
our bending fixture and we'll make the bend. So there's our bend, and I think we're good at 90 there, so
let's see how these parts fit together. So the fit up seems fairly good, but
I want to size this opening precisely. So I'm going to get that block of
wood we used for the initial setup, and use it to trim this opening down to size. So here's our original setup piece
I'll take one piece of wood off of it. Then we can use this piece
of wood to precisely size the piece of metal, and you can see it
overhangs a little bit on both ends. So I'm going to mark that
carefully with a scriber. Then I'll use a combination square
to move that line up a little bit. Now we'll do the same thing on the other end. I'll use the combination square
to move that line up to the bend. Then I'll use a straightedge
to connect the two lines. So now I can trim on these lines. Now we'll trim the second side. So now I'll put these two parts together, and when we do, I think you can see we
can match this wooden template exactly. So that's going to be a very nice fit. So I'll tip this up on end make
sure I have the alignment I want. And I'll scribe this edge for trimming. Now let's mark the other side. And now we can mark this side. So now I'll trim these in preparation for welding. I'm going to cut off a lot of the waste first.
It's difficult to keep the metal flat if you're cutting off too much at a time, so
I removed the majority of the waste. Now we'll make the trimming
cut right on that line. And we'll do the same on the other side. So these pieces are ready to weld together now. So I did the welding and the cleanup off-camera, but I think you can see the
part came out beautifully. I'm very happy with the finished results. And by cutting the parts slightly
oversized and then trimming them, I was able to get a nice snug
fit on both sides of this. So we're able to make a part to
very accurate dimensions as well. So now that you've seen how
easy the Rollation process is, I hope you'll try it for your own projects. I hope you're enjoying this series on Rollation. I'm working on new videos showing more complex
transitions, which I'll upload shortly. I invite you to like, subscribe, and click the
bell to be notified when my next videos launch. I read all the comments and I do
my best to answer every question. Now you can support my youtube
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the video for more information. I'll see you next time!
