[Mar 8] Designing the Box

Today we started our own design process! It sounded challenging but exciting.

Since no one e-mailed any ideas to Oscar, he decided to assign us a project - making a box. There are, of course, some requirements. The box needs to be 2 * 2 inches for each side. It could have any number of sides, although for simplicity reasons, many of us chose cubes. It needs to have 2 fixed sides, 2 movable joints that are either free or friction or one for each category for a bonus (although no one knew what that meant...) Oscar wanted us to give him a materials list. It should be aesthetic, easy to manufacture, and have high performance.


I started my design process. And here is my overall design at this point:



(1) is fixed joint, (2) is movable joint (could be free or friction, depending on how I make it), (3) is a fixed point but not as strong as (1).


I searched for laser cutting boxes, and found this wonderful design:
http://www.redtorope.com/2010/08/beer-mat-boxes/

It is a great design for fixed joints, and this is where I got my (1) joint.

(All from "RedToRope")

I loved this design because then it wouldn't require drilling a hole across the material like (2) does. It would also be very stable and somewhat aesthetic (at least it looks pretty in the picture...) I showed Oscar and he thought it was a brilliant design too so I shared with everyone else.

This is my design matrix for (1) before I tested it out:
Performance ++
Manufacture +
Aesthetic +

Then I started drawing it with Inkscape.

I measured the length of the screw with a ruler, which turned out to be a bad idea because it was not accurate enough for this kind of work. I should have used the electronic ruler. But anyway, the screw was a little more than 2.5 cm, so I made the spot for the nut 2 cm from the top of opening. Then I measured the width of the screw to be 3mm, so I made the opening 3mm wide. Then I measured the width of the nut and made the space for the nut to be that measure. I made the diameter of the little hole 3mm.

Then I set everything to the correct format, and used the laser machine to cut the design. Here is what it looks like when it's assembled:

I was in luck that the screw could just go in and made the joint very stable. Because of the measuring issues, the width of the space for the nut is too big while the length of the space for the screw is too long, so that the nut is movable and not really functional. In fact, I think I might have lost the screw that I was measuring and used the other screw when I assembled it... The hole and the space for the screw were also too small. The crew could be pushed in with a screw driver, but it was really hard and could not be put in back and forth because otherwise it would "eat up the materials" and become looser and looser.

Another problem is that a screw of this size is too big for a 2*2 inch box. It's also not very pretty. Oscar helped me find "0" screw, which should be better for this project.

The decision matrix after the experimentation turned out to be:
Performance + (Can be fixed by using caliper)
Manufacture +
Aesthetic - (Can be fixed by changing to smaller screws and nuts)

Lesson learned today:
1. Always record what materials I used
2. Always use accurate measuring tools, eg. caliper
3. Go step by step. Testing out partial designs before going on to the whole project.

That was all we had time for. I am excited to test out my (2) next class.