Cargo Box | ENGI 210: Prototyping and Fabrication

When I saw this assignment, I decided to make a box for the trunk of my car.

The first things I considered for the box, knowing my plans for it, were size and color.

I decided it would be nice if it were around the size of a milk crate to keep assorted things in my trunk together. Additionally, as my car’s exterior and interior are black, I decided it would be best if the box were black.

Once I had these plans for my box, I started looking for wood with which to build my box. I was pretty surprised to find out there were not a lot of pieces of wood that were a good size to make my box. Because I struggled to find any wood with the surface area and thickness that would make a good box for me.

I thought I would be making the box with solid planks for the sides and bottom, but when I started, I realized there wasn’t a lot of thick wooden plates left, especially those that would let me make the dimension requirements, so I hunted for thicker pieces of solid wood instead of plywood, so they would be stronger because I realized the sides of the box would have to be slated. I found several pieces and made them into several pieces of 12 in. x 1 in. using the table saw and the miter saw.

After this, I sanded them down to be very smooth. Originally, I began sanding with 150, 180, 320, then 400 because I really wanted them to be smooth. After a few, however, I realized the wood I was starting with was fairly smooth and flat, so I began sanding each piece with 320, then the main faces that would be facing outwards and inwards, with 400 grit.

Some of the wood I made into strips had nail holes, so I used wood filler to fill those in. After they dried I sanded the filled area down to recreate the smooth face for the slate.

From the beginning, I knew I wanted this box to go in the trunk of my car. I have been needing storage back there, so I wanted a color to match my car that had black paint and a black interior. I needed to color the wood black, but I also didn’t want to paint over the wood with spray paint. As I had chosen good, solid wood I wanted it to feel like wood, and I wanted a slight hint of wood grain, so I used black stain.

I decided to stain all of my wood pieces before assembling the box because I wanted the box to have a clean, uniform coloring, and I thought if I assembled first, it may be hard to reach some places to stain, like near the joints or on the inside, and there would be obvious lighter spots on the box, making it look obviously processed.

After the pieces dried, I went ahead and started placing the wood in position to finish planning the box. I had some slates that were thicker than the standard 1 in. ones, about 1.25in. I decided to place those onto the square plate that I prepared to be the base so that they could act as the support for the slates to create the sides and screwed them into the plate from the bottom. The rest of the 1.25in slates I used as the initial slate on each side at the bottom to make the base a bit bigger and sturdier. Next, I divided the plates between the sides and played with a few spacing ideas. I settled on having an additional 6 slates per side above the initial planks and spaced them a bit under one inch until the last slate was flush with the supporting posts.

I set the sides I was working on facing up and spaced the slates as planned. I then went through and drilled a 1/8th in. pilot hole through the slates and the posts then screwed in the screws I found. The only wood screws I found that were the correct length (~2.5 in.) for my project were a bit too thick, so even with drilling pilot holes and trying to wiggle the drill to widen them (the next drill bit up was 1/4in and would have been far too big) I found that the wood often cracked when I screwed the screws in fully. However, I kept going with these screws because they were the best screws for the job and because I knew they would be a lot sturdier than nails. As this box’s purpose is to keep cargo, I decided that strength was more important. The available screws also lead to me not countersinking the screws, as on two of the sides, countersinking the screws would make them go through the other side of the wood because they were slightly too long.

After I finished drilling out all the pilot holes and screwing in the screws. I went ahead and did a light sand around the box. Then I took the box to go route it.

I chose the widely rounded bit for the router because I wanted gentle curves on the bottom and top of the box so it wouldn’t scratch me or the interior of my car. After struggling very, very much with changing and positioning the bit of the router, I was able to route the top and bottom edges of the box. Once I routed the box, I did another coat of the black stain over the routed edges and everywhere I sanded the box prior to routing.