The Coupling Piece

Introduction: The Coupling Piece

Hi guys, today I’m going to give you the instructions to make a coupling piece. It’s a tool that allows materials to be coupled in endless possible ways.

This is possible by the attachment of the coupling piece with all sorts of gears that are designed to grab any kind of material, such as clamps, hooks or straps.

The coupling piece can also be used as a gear storage.

It’s is designed in such a way that it can be produced in a Fablab.

So you might ask me, what is a Fablab?

A fablab is a nonprofit, small scale workshop which can be used to transform creative ideas into prototypes. So in there, you can find all sorts of machines such as lasercutters, CNC-routers, 3D printers, Vinyl cutters which you can use to make “almost anything”.

Fablabs are to be found all around the world, so if you wanna find the nearest fablab from you home, you can find it on the fablab website.

Step 1: Materials

The coupled piece is made from several materials:

- 6mm thick PMMA sheets, with a minimal surface of 240x340mm. These are to be found in the fablab, or in a do-it-yourself store

- Three M4 bolts and lock nuts, with a bolt length of 50mm. These are also to be found in the fablab or in do-it-yourself stores

- An allen key, or screw driver or ring spanner, as long as it fits into the head of the bolt you are using

- A pair of small pliers, or a ring spanner that fits into the lock nut

- Linen sheets, with a minimal surface of 400mm2. They are to be found in textile stores, or, often unused home products are made of linen which you can use for this purpose - Nylon rope, between 2 and 5mm thick

- A lighter

- A ruler

Step 2: Lasercutting

The first thing you wanna do is cutting the PMMA and the linen sheet with the lasercutter. For that, you will need to download the adobe illustrator files (see below). The way in which this file can be translated into a lasercutting process can defer from a fablab to another.

sometimes the required file type isn’t adobe illustrator, in that case, open de adobe illustrator file go then to file>export>select the required file type> save>ok

Make sure that you follow the instructions on how to use the lasercutter,

And especially required settings depending on the material you use.

And if that doesn’t help, the fablab staff is there to help you.

Adjust the required height, now you are reading for lasercutting.

If you wanna make just one Coupling Piece, you better lasercut just one layer of linen. For that, you might wanna unbound the thread between the linen sheets.

Don’t forget to put a sheet from a hard material under the linen so that it is as flat as possible during the laser cutting process.

When you are done lasercutting, don’t forget to remove the foil at both sides of the PMMA sheet.

Step 3: Cutting the Rope

Ok the next thing you wanna do iscutting the rope, you might wanna use the lighter for that to avoid dispersed threads at the end of the rope.

Cut the rope in order to get one 400mm long rope and three 300mm long rope.

Step 4: Tying the Rope

Now that you got all the parts, it’stime to assemble everything.

Take the PMMA part with the most holes in it and insert one of the three short ropes in the holes that are next to each other.

Use both end of the rope to perform a dutch bowline (see images).

Eventually readjust the knot that it’s not too far from the ends of the rope, this is a good distance.

Now you can do the same with de two other short ropes, make sure that all the knots are at the same side of the sheet.

Step 5: The Slider

Now take the linen part, fold it in such a way that you can see right through the holes at the border of the linen, and insert the last rope through the hole at the side that is the furthers away from the border, and then insert the rope into to hole next to it. Then go to the neighbor hole, and perform the same action, but then from the other side, repeat this action until the rope went through all the holes.

Now that you have made it through all the holes, make a simple knot at both ends of the rope (see images).

Then, use both ends to make an arrowhead hitch (see images). Now the arrowhead hitch adds a sliding function to the linen part that becomes a bag which you can open and close.

Step 6: Joining Everything Together

Now take a bolt, and you gotta insert it though the PMMA parts. first the bigger circled part, and then the smaller circled part, then into one of the holes of the bigger parts, then again, but from another position, then again, at the same position, and then again, at the last position.

Now you can do the same with the other two bolts.

Now, turn the linen part upside down, fold it in such a way that you can see right through the holes that are next to each other, and insert them through one of the bolts.

Now you can do the same with the other two bolts.

Now only the last part has to be added with the rest. Insert the last part in such a way that the dutch bowline is at the inside of the coupling piece. You might wanna reposition a little bit the linen part and the rope ends to avoid unnecessary material between the PMMA parts

Now insert the lock nut at the end of the bolt, and use the allen key (or screw driver, or ring spanner), and the pair of pliers (or ring spanner) to tighten the PMMA parts with each other.

Turn the lock nut until the PMMA part are almost touching each other.

Now you can do the same with the other two lock nuts.

Step 7: Done!

So here you go, you’ve got yourself a coupling piece, which basically means that you can couple any materials with any other.

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    Interesting. I had actually never heard of this kind of tool before. Thanks for sharing.