Patternmaker PET Wire Straightener

Hello there,

Do you want build your own bottle rope extractor that gives you straight PET strips? but you don't want to spent a lot of money. You can follow our instructions.

First you'll need a few things.

- an old soldering iron
- 2 electrical switches (min. 240 V)
- an engine
- electrical wires (1.5 mm)
- a power strip (min. 2 sockets on it)
- a set of gears
- a bobbin
- a tube (with an bigger radius than your old soldering iron)
- 5 washers
- 2 bolts
- 2 nuts (that fit on the bolts)
- 2 springs
- a sharpener knife
- screw-thread
- wooden planks (thickness 12 mm)
- wooden blocks
- a broomstick

Most of these supply's you can find in your home or workshop.

Step 1: Building the Box

First we'll build the base of the construction.
You will need some wood planks and saw them to the correct sizes.

The ground-plate is 470 x 315 mm.
The long sides are 470 x 60 mm.
And the short sides are 291 x 60 mm.

If your engine is bigger than 60 mm in length, you'll need to adjust to the length of your engine.

Once your planks are ready, you can screw them together like in the pictures above.

Step 2: Bottle Cutter

The next step is to place the knife that cuts the bottle.

You'll need to drill 2 holes that are a size smaller than the size of your bolts.
(e.g. if you have M5 bolts you'll need a drill of 4.5 mm).

You can find the placement of these holes in the pictures above.
The distance between these holes reply's on the outer diameter of your washers.
We applied the rule: the diameter of the washers + 5 mm.
(e.g. We had washers with diameter 30 mm. So we used 35 mm between the holes).

After your holes are drilled, take a bolt. place a nut, 2 washers and a spring on it (in this order).
Then screw the bolt with its attachments in one of the holes. Do the same for the other hole.

Than take the sharpener knife and place it between the washers you just used.
And clamp them together. To make sure the knife is stuck, you can use glue.

Step 3: Bottle Holder

The next step is to build a construction that keeps the bottle on its place as it spins around.

First, on the bottom of the box, you have to glue a wood block. The block needs to be centered under the holes of the bottle cutter. this will give your holder more stability.

Take the broomstick and saw it in 2 sticks of 400 mm.
Than drill 2 holes in the box like in the pictures. They are vertically aligned with the bottle cutter and are symmetrical to the center of the box. The diameter of the hole is the same diameter like the broomstick.
When you drilled the holes you can glue the broomsticks in them. The sticks need to be at least 35 mm above the surface of the box and as straight as possible

Now take another woodblock with a min height of 25 mm and saw it in 230 x 55 mm. Then drill 2 holes with the same distance from each other like the broomsticks. the diameter is the same as the outer diameter of your PVC-tube.
Drill now a hole in the middle that's 10 mm deep and has a diameter 28 mm. Than apply a chamfer on that hole. Than glue 2 PVC-tubes in the outer holes with hot glue.

Step 4: Soldering Iron

In the next step we will place the soldering iron.

Take the soldering iron and take the handle off and take the point out.
Now drill a new hole in the box with the diameter +- 5 mm bigger than the tube diameter of the soldering iron
Once your hole is drilled, you can screw the iron on the box.
(e.g. our Soldering iron has a diameter of 10 mm, so our hole is 30 mm)

To make it safer to use the tool, take a tube with a diameter that's at least 10 mm bigger than the diameter of the iron and sticks at least 50 mm above the iron. Than cut out a slot with a grinding tool. The slot has to be 20 mm wide and an angle of 225°. And stands 20 mm from the edge of the tube.

Then take a woodblock and saw it to the given dimensions that stands in the pictures.

Step 5: Bobbin

In the next step were going to place the bobbin and the engine.

We need the bobbin to turn slow, because the wire must warm up to straight. So we'll let in turn at a speed of 10 rpm.
First we need to check if our engine turns 10 rpm. If it goes faster you'll have to build a gearbox that reduces the speed of the engine to +-10 rpm.
The last gear must be mounted on the bobbin. You can crew them on or do it like us.
We had a plastics gear with an axis on. So we used it to connect the gear to the bobbin. Using a square shaft prevents the gear wheel to not slip.
(e.g. We only needed 2 gears, one on the bobbin and one on the engine, to get the proper speed.)

Now drill a hole in the box. The dimensions are given.
place a piece of screw-thread in that hole. That's going to be our rotating point of our bobbin.
you can place the bobbin on the axis to check if it fits and if the bobbin can rotate easily.
If its to loose. you can use a wooden disk that fits and grips in the hole of the bobbin. than you drill a hole in the middle the same diameter of your axis.
And if the bobbin doesn't rotate smooth, you can place washers on the axis. that way you'll have less friction.
Drill 2 holes with diameter 7 mm on the top of your bobbin, like in the picture.

Now place your gears on the box and drill a hole where the axis of the engine needs to be. Make the hole slightly bigger than the axis, so it can rotate.
Now mount the engine on the inside of the box.

Step 6: Electrical Wiring

The last thing we need to do is the electrical wiring.

First mount the switches on the place you want. Than solder your switch with the engine.
Than solder one cable of your socket to the 2nd pin on the switch, and the other cable to the free pin of your engine.

for the soldering iron cut one of the cables that goes to the iron head (not the green-yellow one).
connect the one end of the cable you just had cut to on pin of the 2nd switch.
And the other end to the other pin of that switch.

now mount the power strip on the inside of the box. You can make a slot to place the cable in it, so your machine doesn't wobble.
now connect the sockets of the engine and soldering iron to the power strip and hide the cables.

Step 7: How to Use the Tool

Switch the supply for the soldering iron on.
Take a bottle and cut the bottom off.
Place the bottle on the knife and turn while slightly pressing.
When you see a piece of strip coming out the bottom, place the block to hold the bottle on the bottle.
Pull the piece of strip along the soldering iron and lock it in the bobbin like in the picture.
Switch the supply for the engine on.
Wait and watch to see if everything runs correct.
If the bottle is exhausted, switch both switches off.
and place a new one.

From this resold you can make many things.
We braided rope with it. The rope will be strong, because PET has a lot of pull.