Project Report

If you haven't done so already, check out the Live Prototype tab for a more general overview of how the capstone internship period went! Here in Project Report, the process and findings from the active prototyping phase would be presented. At the bottom of the page is a slideshow displaying more intricately the requirements of the tab, but until then, enjoy the day-to-day journey of experimentation and prototyping!

Day 1

On Monday, the 16th, I spent about an hour looking for sand in the residential estate and found some that the owners freely gave me, a sack of 25kg (which wasn't all used up). I purchased a larger melting pot and a sand sieve for 2700 Naira (~$7). After weighing some bottles, I averaged one (not the soda bottles, but the ones for water) to be between 16 and 18 grams. With 30 bottles, we would have about 500 grams of plastic. We’ll have a series of experiments to determine our formula: I started with doubling the sand per plastic, a 2:1 ratio. The green stove we had brought out from the house took a lot of time to work, precisely 30 minutes 31 seconds, and it didn’t melt one bottle. We had to drive out quickly to get camp gas and fill it up (12,500 and 3000 Naira, respectively, total ~$38). I ignited the flame, and after 2 minutes, the first bottles were in and melting; by 10 minutes 42 seconds, all the 30 bottles had melted. What else did we learn? Shredding the plastic could accelerate widespread melting and shorten the time; greasing the mould makes the block come out much easier (the first was not greased, and it was difficult to remove; we hammered it out, and it broke).

Day 2

On Tuesday, I tried a 1:1 ratio: 60 bottles to 950 grams of sand. I sieved the sand, which made the sand particles smoother and more even, and after I shredded the first ten bottles, they went in quickly! However, shredding them up satisfactorily took precious time. After 24 minutes 40 seconds, all 60 bottles were in; about 10 minutes later, though, the lid of the melting pot began to push off by itself, and thick fumes started coming out the pot. Fire began to flash along with explosive sound effects phasing in and out; I had to take it off the fire and finish up from the concrete ground. I couldn’t let the 60 bottle batch be wasted and burn up, so I added the sand regardless and poured it into the mould. For the second round, I tried the 2:1 ratio again but mixed the sands (red and sharp) (up until this point, I had been using only the red plaster sand) and dried the sand (up until this point, the sands were somewhat damp), it took form. What did we learn from Tuesday? Different plastic bottle types have different melting rates; removing the moisture from the sand leads to a mixing process with less vapour; nylon plastic may be better for creating bricks (flashback to last year’s prototype). We entertained the following question as well: would it be better to have brittle bricks (in terms of ratios (like twice as much sand to plastic) but thicker ones, or thinner bricks but harder?

Day 3

By Wednesday, we had used up to 120 bottles, and I adjusted the ratio of sand to plastic to 1.5:1, maintained mixing the red and sharp sands, and used 30 bottles. The first one went well, but 10 minutes 50 seconds into the second, it caught fire for no apparent reason. This was the second time I came close to aborting the mission, but I made a few guesses and changed the approach: I would leave the lid off the pot for most of the time (as the top causes the internal heat to sky-rocket), and I would reduce the number of bottles I put in. I noticed the final bricks were rough around the edges and identified that the brick mould had introduced a quandary. At the end of the day, I believed I had a formula I could work with.

Day 4

Thursday started off promising; it seemed I had found my rhythm. I made five bricks and used 111 bottles. From Wednesday, I realized that salvation likely lay in the mixture–that is, how many bottles, how much sand (I had been doing 50:50), how much time between the steps? So I stepped the ratio closer to 1:1 by making it 1.25:1 – 300 grams of sand to 15 bottles. I discovered that the plastic-type affects the bricks' colour and appearance; it would probably be better to use one kind of plastic per brick for internal consistency. On Thursday, I ended up making 10, 8 of which were useful. I really could have done with a new brickmould though, but time.

Day 5 & 6

On Friday, I used the same recipe but stepped up the bottles to 20. I made 9 brick tiles, 8 of which were good. Saturday followed the same pattern, and I had exhausted all the bottles in storage by the 8th brick. At this point, there was no way of getting any more bottles (especially considering the following day was Sunday), so it seemed like I was stuck. Regardless, I calculated that if I continued to make 8 bottles per day, I should have had enough bricks for the strip in the police station by Wednesday of the following week. Something is worth mentioning about the production process: bottles had to be prepared—I had to remove the wrapping of each bottle, hundreds of them, and at some point, group them into soda bottles, clear water bottles, blue tint water bottles, etc. To prepare 20 bottles, it took me 3 minutes 10 seconds. And at this point, to produce the ~24 bricks we had by now, the fire had been on for at least 6 hours 30 minutes.

Day 7 & 8

Sunday arrived, and mid-day, we recalled a relative in the estate whom we had not collected bottles from. We went there and acquired over 200 bottles. This day was also when we tried to officially test the strength of the brick, it crushed under the weight of the car. I began to consider more equitable ways of deriving an idea of its durability when I realized that without (hydraulic) compression, they would (and should) be brittle.

Monday, I began to consider more the finessing of the bricks, making the edges smooth and stepping up the aesthetics. I went to the carpenters' village first, where they told me sandpaper would not work on the bricks. So I went to my welder, and he gave me a manual grinder and sandpaper free of charge and said I should use those; he also used the angle grinder on one of the bricks I had shown him, and it made it look handsome. On my way back, I passed by the police station, where the DPO has assigned an abandoned police van to be the collection site for plastic bottles for the project. I packed as much as I could, several sacks and straw bags full, over 250 workable bottles. When she heard I planned to call a Bolt to move them to my workshop, she offered the police van and had the driver take me and all the bottles home.

Day 9 & 10

At the end of Tuesday, our target number of 50 bricks had been attained (and surpassed by 2), the fire had been on for over 15 hours and the gas still hadn’t run out. I considered the inscription I would prefer to have on a brick when installed at the station: ALU Capstone Project | Operation 414 | Ogudu Police Station Area H | date. I also heeded my supervisor’s comment on using resin art to finesse the bricks’ aesthetic appeal. Unfortunately, a source I reached out to said they didn’t have supplies at that time.

On Wednesday, I counted the bottle covers I had been keeping on the side (because I did not melt the caps with the plastic bottles (due to the melting pace differential)), and these were the results: white covers (183), red covers (36), orange covers (23), yellow covers (19), green covers (27), black covers (6), brown covers (1), light blue covers (150), dark blue covers (855). By the afternoon, I was ready to install the bricks, each weighing about 0.76 kg, but a prolonged power outage interrupted the water supply, and the forecast of the day was set to rain. Eventually, I made it to the police station with my family friend Anne Eta. We waited for over 4 hours for those assisting us; they did not show up, and we (the police, Anne and I) changed plans to do it the following day.

Day 11

By 9:00 AM on Thursday, we were at the station, and a few moments later, Mr Moses Effeh showed up; the DPO called him to aid the installation. He works in the construction industry and so quickly organized two people to begin the dig and preparations. Within two hours, the bricks were laid, and he thought it would be an excellent idea to firm the setup with cement, which we proceeded to do. As that was going on, Mr Moses had found someone who could engrave the project details into the concrete and so we had a chat with him. Baba called 6K for us; it was fair, and his idea was good, but Anne and I had to decline, for we were no longer interested in accumulating costs. We decided we would create proper stencils ourselves and permanently paint over them there.