Assignment #2: Make a press-fit structure

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This time I really tried to document my process.

Phase 1: Brainstorming

Thinking about what to build for this assignment, I realized that there are several themes that I want to incorporate into whatever I end up making:

1. It should have real functionality and could be useful (at least for me)

2. Each unit would stand on its own and serve a purpose, but also be scalable/expandable – like a building block for some larger structure

3. I want to experiment with different types of press-fit connections – some of them should be easier to disconnect and some will be more “permanent”.
   This could be useful for a more “directed-disassembly” - if force or pressure is applied to the structure, the designer can influence which connections will break first.

4. I really like motion and want to do something that incorporates some sort of circular motion into the press-fit structure.

Phase 2: The drawing board

I think that I'll make a Modular-Expandable-Super-Structured-Wine-Bottle-Holding-Whatchamacallit. Or in short – a MESS.

The basic unit will be a folding storage unit that opens up and holds 6 bottles. These units would be stackable on each other and create a bigger storage unit. I am wondering if I also want to physically connect such units on the sides too – but right now I'm not sure a physical link is necessary since they can just be placed next to each other).

This way your friendly-neighborhood-wine-enthusiast can start building up his collection gradually from one unit up to a whole wine cellar...

I've been working with the Open Office draw program. As was mentioned in class, the most useful feature is indeed the ability to add and subtract shapes in order to make more complex ones. The whole design can be done with combinations of basic circles, triangles, and rectangles.

Some notes to keep in mind:

• Connectors

There will be 2 types of connectors:

• "snap" connectors: The basic unit will be constructed with “semi-permanent” links that will be harder to disconnect – you'd have to apply pressure at specific points or even use some tool to disconnect them. They will also act like a hinge and allow for rotational motion.

  •   

                Things to look at:
                    - How should the groove be designed to allow for disassembly – how deep, how wide?
                    - Should it be easy to disconnect them by hand, or will it be done with some tools (like a pair of pliers, etc.

• The links between the units will be more “transient” - easy to connect and disconnect. They are mostly there to keep the bigger structure in place.

• The hinge
  I want to to make sure that the “X” beams rotate but will be stopped at the right angle. I plan to do it with a carefully designed connector pin, that will look something like this:

        And hold the “X” beams in the desired position like this:

• Materials

  • It should be sturdy enough to hold 6 bottles of wine. If the units are going to be stacked on top of each other, things may get heavy for the bottom one, so I'll have to see if that's feasible or if I should add some more support.

  • I guess the final material will be acrylic. I'm pretty sure that the “X” beams will have to be with the thickest acrylic that I could find, but maybe other parts can be with a thinner kind.

  • I can start practicing on cardboard and tweak the structure to what I had in mind. Experimenting with the connectors, though, will probably have to be done with acrylic, since the type of material will greatly affect the connectors.

Phase 3: Experimenting with the basic shapes and materials

Here are some results of experiments I did with the different materials. I started with cardboard, and concentrated first on the shapes and features of the connectors.
It was soon evident that cardboard is not good to test the snap connectors, since it's too delicate.

Another thing I realized is that even if I figured out a good shape for the connector, once I added material to it in order to get the actual shape I wanted it to be part of, it changed the pressure points and weaknesses of the part, and it snapped in places I hadn't foreseen originally. Most of these sensitive points are pretty logical once you think about it, so as I advanced I was able to better predict which parts would be more sensitive than others and try to solve it in the design before actually building them.

I also had many thingies like this left over from the holes of the connectors:

Any ideas what to do with these? (aside from miniature poker chips)

I also found out that OpenOffice Draw has a neat option to export the drawing file into a webpage, so here is my OpenOfficee scratch pad, which also shows how the final design evolved as I progresses with the experiments.

Phase 4: Assembling it

So here's the final version. I made a 2 bottle version and a 6 bottle version. Both seem to hold up pretty nicely under the bottle weight.

Six Bottle Holder:

Open

Folded

2 Bottle Holder

Open

Folded

Group photo:

The parts:

Six Bottle Holder

Two Bottle Holder

Inter-Holder-Connectors

I ended up doing them as stand-alone connectors. Originally the idea was that I wanted to save material since if I hard-coded it into the arms of the holder, as in the original design, I would have to actually manufacture several whole devices so I can stack them up and see if my angles are correct.

By making each connector be a standalone, its much easier to test them, and they can be connected to the basic device and serve the same purpose. Since they can rotate freely, they can adjust to any angle of the "X" joint, and the units will stack up vertically.

Phase 5: It actually works!

(I could only find 4 bottles at home..)

And after a few sips:

Phase 6: Get more wine

Donations are welcome.