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Desktop Injection Molding Machine Final Project Report
Full text linkThis report outlines the process, tests, and research conducted to develop a desktop plastic injection molding machine for use in K-12 classrooms as an educational tool to introduce engineering topics earlier in children\u27s education. The key objectives were to create a functional prototype that is safe for classroom use, is easily integrated into curricula, weighs under 80 lbs for portability, and can produce an 8 inch3 molded piece in a reasonable timeframe.
The final design features a single-screw extruder coupled with a hand-cranked planetary gear system for interactivity. A 2x2x2 inch maximum mold volume was chosen to reduce the pressure and torque required, enabling the use of a hand crank. The machine incorporates a clear housing for visual understanding while shielding users from heating elements. All components are modular for easier cleaning and modification. The prototype weighs approximately 70 lbs and measures 3.75 ft in length, allowing it to be easily moved by two adults and placed on a standard desk.
Extensive research and development went into each subsystem design. The screw features feeding, transition, and metering zones with different heating requirements and geometry to efficiently melt and mix the plastic. The nozzle interfaces the barrel to the mold. Electric heating bands controlled by PID controllers and thermocouples heat the outside of the barrel. The planetary gear system with hand crank enables sufficient torque while keeping the machine interactive. The aluminum extrusion and acrylic housing protects users from hot components.
We tested the functionality of key subsystems. The screw successfully transported unmelted pellets through the barrel without deformation. Heating elements reached target temperatures within 8 minutes and maintained stable temperatures, while the acrylic housing remained safe to touch. Calculations confirmed the gearbox provides enough torque reduction for hand cranking by older students and teachers.
While not yet fully functional, the prototype has met several key objectives - it fits on a desktop, weighs under 80 lbs, is safe for children, and meets temperature, pressure and VOC safety considerations. To reach full functionality, the screw still needs to be connected to the gearbox through a part that is soon to be delivered, after which subsequent testing can be conducted on clamping force, gear torque, and the heated feeding system.
Substantial progress has been made towards creating an educational desktop injection molding machine that can enhance K-12 STEM education. The machine incorporates an efficient extruder design, an interactive hand crank, visual clarity for learning, and safety features suitable for classroom use. With a clear path outlined to complete the remaining tasks, the project is well-positioned to produce a working prototype that achieves the goal of introducing students to engineering concepts through hands-on experience with injection molding. Recommended future work includes finalizing the mechanical connections, conducting the identified additional tests, and developing curricular materials to help educators integrate the machine into their lesson plans. Overall, this desktop injection molder shows great promise as an engaging teaching tool to inspire the next generation of engineers
Emerson among the Methodists
Full text linkThis essay examines the influence of Methodism on Emerson. During Emerson’s lifetime, Methodism exerted extraordinary influence on American religious life, yet he offered little comment on this important religious movement. In spite of this omission, this essay argues that Methodism shaped Emerson’s ideas about oratory, prayer, and self-determination. This essay examines two Methodist figures whom Emerson repeatedly cited as important influences: famed Methodist minister Edward Thompson Taylor and a less-remembered farm worker named Tarbox, whom Emerson met in his twenties and repeatedly mentioned in his journals. Emerson took inspiration from both men, but seems to have been unaware of the sectarian inflection of their influences; in adapting these men’s ideas in his own writings, Emerson repackaged Methodist theology as denominationally ecumenical and enabled Methodist belief to gain wide circulation among some of its most ardent critics. As a result, Emerson unwittingly became one of Methodism’s most effective champions
New geochemical and geochronological insights on forearc magmatism across the Sanak-Baranof belt, southern Alaska: A tale of two belts
Full text linkThe Sanak- Baranof belt includes a series of near- trench plutons that intrude the outboard Chugach– Prince William terrane over ~2200 km along the southern Alaskan margin. We present new petrological, geochronological, and geochemical data for comagmatic microgranitoid enclaves and granitoid rocks from the Crawfish Inlet (ca. 53– 47 Ma) and Krestof Island (ca. 52 Ma) plutons on Baranof and Krestof Islands, as well as the Mount Stamy (ca. 51 Ma) and Mount Draper (ca. 54– 53 Ma) plutons and associated mafic rocks that intrude the Boundary block at Nunatak Fiord near Yakutat, Alaska, USA. These data suggest that intrusion of the Sanak- Baranof belt plutons is actually a tale of two distinct belts: a western belt with crystallization ages that young systematically from west to east (63– 56 Ma) and an eastern belt with crystallization ages ranging from 55 to 47 Ma, but with no clear age progression along the margin. Hf isotope analyses of magmatic zircon from the western Sanak- Baranof belt become increasingly evolved toward the east with εHft = 9.3 ± 0.7 on Sanak Island versus εHft = 5.1 ± 0.5 for the Hive Island pluton in Resurrection Bay. The Hf isotope ratios of eastern Sanak- Baranof belt rocks also vary systematically with age but in reverse, with more evolved ratios in the oldest plutons (εHft = +4.7 ± 0.7) and more primitive ratios in the youngest plutons (εHft = +13.7 ± 0.7). We propose that these findings indicate distinct modes of origin and emplacement histories for the western and eastern segments of the Sanak- Baranof belt, and that the petrogenesis of eastern Sanak- Baranof belt plutons (emplaced subsequent to 57– 55 Ma) was associated with an increasing mantle component supplied to the youngest eastern Sanak- Baranof belt magmas. These plutons reveal important information about offshore plate geometries and a dynamic period of plate reorganization ca. 57– 55 Ma, but a clearer picture of the tectonic setting that facilitated these Sanak- Baranof belt intrusions cannot be resolved until the magnitude and significance of lateral translation of the Chugach– Prince William terrane are better understood
THE TOWER’S LONG SHADOW: THE ROLE OF THE TRANSLATOR PROTAGONIST IN ANN PATCHETT’S BEL CANTO AND R.F. KUANG’S BABEL
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Bad Plants
Full text link“Bad plants” represent the seemingly unexpected and startling forms of plant power overlooked by many modern, industrialized societies that treat vegetal beings as mere resources instead of animate, world-shaping forces. Since science fiction and fairy tales often explore more openly animistic visions of non-human life, such texts provide ample possibilities for reconsideration by critical plant studies of our human-plant relations both cultural and ecological. For example, both Jack McDevitt’s 2001 science fiction novel, Deepsix, and Ludwig Tieck’s 1799 fairy tale, “Faithful Eckart and Tannhäuser”, feature “bad plants” that bring human beings violently back into the plant cycles they assume they have left behind with advanced culture and/or technology. In McDevitt’s case, we find sexualized predatory flowers on an alien planet, and in Tieck’s, flower-filled caves containing Venus herself living deep in the forested mountain. The wildly sexual blossoms lure human beings back into their botanical cycles, thereby expressing and, simultaneously, hiding our ecological embeddedness that is actually quite mundane. The lurid visions of “bad plants” contain potentially profound, if convoluted, ecological truths about our full dependence on, and ongoing immersion within, the activities of the domineering green photosynthesizers
DIGITIZING THE DUMP : AN ANALYSIS OF DIGITAL EXHIBITIONS THROUGH DOCUMENTATION OF ARCHAEOLOGICAL FINDINGS
No full textDon’t come crying to my funeral
Full text linkIn this article, I describe a Makushi wake in Guyana, where an opposition was drawn between people in mourning and their perception of others who appeared to them to be much more like partygoers. This opposition in affective states was made evident through the enactment of associated oppositions in bodily practices: feeding and eating, speaking and singing, and forms of social availability. Rather than consider the divergence in affective states as a form of moral disorder, I argue that an affective divide allows grief to be expressed by the mourners and safely circumscribed by their still-living community, who continue to enact Makushi people’s most socially valued capacities. I further consider the way in which Makushi ideas about death and funerary practice have changed over time and suggest that the affective divide is an enduring feature of Makushi grief work, albeit within a rite transformed
Replication and growth in cassava cultivation and uxorilocal women’s relations among the Waiwai: a mother\u27s reckoning with death and social change
Full text linkThrough an ethnographic examination of the shared capacities of cassava and womanhood for what I term growth and replication, I argue that Waiwai sociality seeks to curtail the trajectory of life towards finite death through the intervening act of cutting and replanting or replicating life in a vegetatively inspired form of the “episodic present” (Strathern 2021). An extended vignette demonstrates how these features of Waiwai sociality take shape in mother-daughter and sister relations at the core of uxorilocal residential living, and in a senior woman’s reckonings with illness, death, and social change