CAST IN STEEL “BOWIE KNIFE COMPETITION” TECHNICAL REPORT UNIVERSITY INSTITUTO TECNOLÓGICO DE SALTILLO COMERCIAL STEEL FOUNDRY MAHLE PLANTA CAMISAS, RAMOS ARIZPE FACULTY ADVISOR DR. EFRAÍN ALMANZA TEAM MEMBERS MAGDIEL ALVAREZ EDGAR HUERTA MIGUEL HERNANDEZ JUNE 2020 ABSTRACT A 12-inch blade bowie knife was fabricated using a ferrous high alloy for the best quality and properties, such as, toughness, strength, machinability, impact and corrosion resistance. There were used two different types of molds. One made of refractory cement (60%Al2O3 - 40%SiO2), and the other made with a simple green sand mixture. After experimenting with both of them, it was determined which could be the best option when pouring the metal at very high temperatures, and also which could replicate on the best way the shape of the knife, that consist on 1/5-inch thick (4mm) and 18-inch long (including tang and blade). The guard and the pommel were made of bronze, and along with the design and the handle, were characteristics thought, to give the knife a complete control and well balance over its total weight. Acknowledgements The team involved on the making of this report, and the entirely project is completely grateful for all the help and assistance provided by: Mahle Planta Camisas whose guidance and supported material were essential for the fabrication, machining, and properties of the knife. All the teachers from the Instituto Tecnologico de Saltillo disposed to support, advice, provide the media, knowledge and technical analysis to succeed on the project. All people involved in order to complete the project, carpenter for its support making the model for the casting, and people of Helical SA de CV for machining operations. Table of Contents 1. Introduction .................................................................................................................................. 1 2. Historical Reference and feautures .............................................................................................. 1 2.1 Main features and designs ......................................................................................................... 2 3. Design and model ........................................................................................................................ 7 3.1 Blade and Tang .......................................................................................................................... 7 3.2 Crossguard ................................................................................................................................ 8 3.3 Handle ....................................................................................................................................... 9 3.4 Pommel ...................................................................................................................................... 9 3.5 Final Design ............................................................................................................................. 10 3.6 Model ....................................................................................................................................... 12 4. Casting process ......................................................................................................................... 13 4.1 Molding .................................................................................................................................... 13 4.2. Refractory cement mold and casting ................................................................................... 13 4.3. Green sand mold and casting ............................................................................................. 16 4.4 Alloy ......................................................................................................................................... 22 5. machining and assembly ........................................................................................................... 24 5.1 Blade .................................................................................................................................. 24 5.2 Guard and Pommel ............................................................................................................ 28 5.3 Handle ............................................................................................................................... 30 5.4 Assembly ........................................................................................................................... 31 6. Microstructure Analysis, Properties and defects ........................................................................ 33 7. Conclusions ............................................................................................................................... 38 References ........................................................................................................................................ 40 1. INTRODUCTION From the kitchen to army, knives are a very common instrument or device that consist in a large sharpened and thin sheet of metal. They were used since ancient ages for hunting, survival, defense, cutting, to transform big pieces of food into more little and eatable pieces. The principle of a knife is the same, that is something that even history cannot change. However, there are knives with different applications, or specific uses, and depending the application, knives varies on their shapes, jagged edges, sizes, manufacturing process, handles, metals alloys, etc. Bowie knives are the type of knife that has become very popular since their very particular design, interesting history, uses and aesthetics. On this technical report, a complete description is given for the fabrication process of a Bowie knife. The main purpose of the manufacturing, was to use the casting process to obtain primarily the shape, that includes the blade and the tang. This is clearly challenging, because knives are commonly fabricated by forging, or just machining, due to their very small thickness, something that is hard to achieve by metal casting. The steps for the fabrication were the following: design process, casting, machining, sharpening and polishing; meanwhile the guard and pommel were also manufactured. 2. HISTORICAL REFERENCE AND FEAUTURES First of all, it was necessary to determine how the knife was going to look like, which properties it should have, ideal materials to get those properties, and size, in order to get a completely useful and beautiful knife. It was necessary to search what makes a knife a Bowie knife, so, that way it can be proved and ensured that the knife fabricated along this report is an authentic Bowie. History says that the Bowie knife was designed by Rezin P. Bowie and he gave it to his brother James Bowie for protection after he went bullet wound. After recovering from the shot James and his knife becomes very popular at the “Sand Bar Fight”, where after being shot at one lung and repeatedly stabbed with swordcanes, James on a last effort rise and sank the knife on its aggressor heart. Despite this, nowadays there is not an exact representation, of how does the first Bowie Knife looked like. Page | 1 The description of the original Bowie knife paraphrasing Norm Flayderman's book, “The Bowie Knife: Unsheathing an American Legend” (2004), the knife was made for hunting, and the blade was 9¼-inch large and 1½-inch width, was a single edge, was not curved, and did not had a hand guard. The knife was much more like a triangular blade or a “Butcher knife” like how was described at that time. Regardless of its original shape, Bowie knifes soon assumed some of their legendary characteristics, with a crossguard, and a deep remarkable clip-point. It was described by researcher Russell T. Johnson on his article “The Bowie Knife and the Arkansas Toothpick” (2006) as a knife that must be long enough to use as a sword, sharp enough to use as a razor, wide enough to use as a paddle, and heavy enough to use as a hatchet. On figure 1, different types of blades are shown; the “clip point” type of blade, shows the respective shape of a Bowie Knife. Figure 2.1. Different types of knife blades. The “clip point” type corresponds to the shape of a Bowie Knife. 2.1 Main features and designs Now that it has been discussed about the very popular history that surrounds Bowie Knives, it is going to be described the principal features that compound the actual designs. One example of a generic scheme/shape, of different parts of a Bowie knife, is represented on Figure 2. As it can be seen, the typical clip-point shape, a crossguard, and pommel, are present. Some other variations could be encountered, with a jagged edge, fuller, or no pommel, but basically that is how many Bowies knives look like, and the parts which compound them. Page | 2 Figure 2.2. Different parts that compound a Bowie Knife. This kind of knives are very particular, and may be easily differentiated from other knives. However, for a better understanding and quick recognition, a list of some of the key characteristics, that illustrate on the best way Bowie Knives, accompanied with a brief description of each, are the following: Clip-point blade shape: As shown on the figure above, it can be described as a cut-out concave area, resulting on a well- balanced and high-control knife. This shape provides a sharp and thin point, perfect for tasks where precision is required, such as chopping, skinning and piercing. Despite its many advantages,