Summary of Construction

The construction of the bridge will utilize raw balsa wood, which would be ordered from online suppliers in bulk to allow for plenty of materials to work with to create the necessary parts. Should there be complications in the construction process, there’s plenty of material to make replacement parts. Other parts which include the steel rod, spools, and pulleys will be ordered through both local and online suppliers. Construction will occur in an orderly fashion, firstly starting with the actual design of the bridge itself. Any of the raw balsa wood materials will be measured and cut to their proper sizes to fit into the designs of the bridge and articulation system. The project is comprised of about 21 parts based on Design #4 from the design phase of the project, and will have about three sub-assemblies, which all three will be combined to make an entire assembly. The first sub-assembly is the bridge itself, which will comprise of all the segments and the road deck to make the frame. The second sub-assembly is the articulation mechanism, which are the pulley, spools, and the steel rod. There will be two sets of this assembly, for which they will go into the third sub assembly, which is the frame of the articulation system. Then, all these assemblies will go together on one bigger assembly that comprises the bridge frame, the road deck part, and the complete articulation system

Methods During Construction

With these parts, certain tools will also be used to be able to cut and shape the parts into their design specifications to be able to construct the bridge. Some of these tools include a metric ruler, a pencil for marking measurements, a miter box for accurate angular cuts, a razor saw to cut through the balsa wood smoothly, a hacksaw to cut through the steel rod, an X-acto knife for smoother cuts on balsa wood as well as making diagonal cuts. For the most part, the tools should be sufficient to create the parts manually, the rest of the parts would be ordered online to perform other tasks for the bridge.

Changes and Revisions During Construction

During the construction phase of the project, much of the original decisions in Design #4 were kept. However, there were a few adjustments and additions that were made to improve the design. Firstly, was a removal of a single bottom frame in the middle and replacing it with just longer support segments. The decision behind this was that the support segment was in the way of the center hole of the road deck and wouldn’t be able to test for loading unless that was out of the way. The next decision that was made was the adjustment of the smaller hole positions on the road deck. These ones were also on top of the shorter support segments on the bridge frame and had to be adjusted closer to the center line of the road deck. Another decision related to the road deck that was made from necessity was using Imperial drill bits for holes. These were the closest ones to the design specifications. For the smaller holes, it was within tolerance, but for the larger hole, its well out of tolerance. However, it should still be able to insert the 8 mm diameter rod through it when testing happens.

There is some thought into making additional redundant supports for the bridge design to reinforce it. Perhaps an additional design to support the side frame and rising arc verticals. Another was to potentially use some of the raw balsa wood sheets since there’s still a lot of those materials for supporting the bridge design, maybe cutting them to proper size and gluing them to the side for added support. Much of it are still ideas, but would most likely would be put into the design since there’s still a lot of weight that can be added to the bridge that would still be within project parameters, and there isn’t really much of an issue into adding additional supports to help the bridge in general.

Issues During Construction

There are a few potential manufacturing issues that can come up during the construction phase, especially since the construction will utilize tools and materials from home. For instance, the saw that will be used to cut the steel rod into appropriate sizes can break or become damaged, requiring one to purchase a replacement saw. The next issue can be that some parts such as the steel rod wouldn’t be available at a local store, and it may result in having to go to another store or placing an order online. This wasn’t an issue, as the local store had the steel rods in stock. It was even checked on their online store to be sure. Another issue might be that the deliver parts and resources would come up damaged or defective, which would probably lead to having a refund and re-ordering the parts and resources or having to find a similar alternative. So far, the materials that have arrived didn’t have any noticeable defects. The last issue that could arise is the potential need for additional parts or raw material, which for a few of them would take quite a while for the order to be shipped to the required destination, taking up time in the construction phase of the project. This issue shouldn’t arise in the preliminary stages in construction, and there is confidence that the parts and raw material present are sufficient, but this issue should be taken into consideration just in case it arises later.

A minor issue that came up during manufacturing was trying make non-standard cuts with some of the diagonal segments. Originally, most of the cuts have been made using a miter box and a saw, and there wasn’t much in the way of issues. But once the manufacturing of diagonal parts had to be done, their design required much different angles than the 30° and 45 °angles provided on the miter box. While a precise angle cut would have been desired, it was decided to go through with the manual angular cuts and try to “ballpark” the angles enough that it can fit into the bridge design with glue, making any adjustments as necessary. So therefore, the issue was resolved.

Constructed Parts

Construction Workspace

Basic Construction Process (Video)