Peer-graded Assignment: Module 3 Peer Review同伴互评：模块 3 作业

The purpose of this assignment is to give you the opportunity to apply the concepts you have learned in this module and to discuss some of the key ideas of the module in your own words. Follow the instructions provided and respond to each question. This a required activity for this module.
本作业的目的是让你有机会应用在本模块中学到的概念，并用自己的话讨论模块中的关键思想。按照提供的说明回答每个问题。这是本模块的必做活动。

Submit your answers to each of the questions based on the prompt provided on the My Submission tab. Enter your answers directly in the spaces provided in the My Submission tab. You may save a draft of your work as you go, and you can come back later to continue working on your draft. When you are finished working, click the Preview button, verify your identity, and then click Submit for Review to submit the assignment.
提交您根据“我的提交”标签页上提供的提示提出的每个问题的答案。直接在“我的提交”标签页中提供答案的空间内输入您的答案。您可以在进行过程中保存草稿，稍后回来继续编辑草稿。完成工作后，点击“预览”按钮，验证您的身份，然后点击“提交审核”以提交作业。

Grading Criteria Overview 评分标准概述

You are required to evaluate the submissions of at least THREE of your peers based on the instructions and rubric provided. You may begin giving feedback to other students as soon as you submit your assignment; click the Review Classmates tab to begin. Feel free to provide additional reviews beyond the three required!
您需要根据提供的说明和评分标准，至少评估三位同行的提交作品。您可以在提交作业后立即开始对其他学生进行反馈；点击“查看同学”标签开始。请随意提供超出三个要求的额外评价！

This assignment is worth 30% of the course grade.
这项作业占课程成绩的 30%。

As you review your peers, points should be given only for correct/reasonable answers as specified in the rubric provided; incorrect/unreasonable answers get zero points.
在您评估同行时，应仅根据提供的评分标准给予正确/合理的答案得分；错误/不合理的答案不得分。

Examples of Good Feedback 良好反馈的示例

For subjective questions, the score should not be based on whether or not you agree with the answer but rather on whether the answer is complete and well-supported.   
对于主观性问题，评分不应基于你是否同意答案，而应基于答案是否完整且有充分支持。

Both content and organization are important components of a response. Good writing is confident and clearly focused with relevant details to enrich the content. Good writing also follows instructions, such as word limits, and offers requested information.   
内容和组织是响应的重要部分。优秀的写作自信且明确聚焦，包含相关细节以丰富内容。优秀的写作还遵循指示，如字数限制，并提供所需信息。

A clear and concise answer is preferable to a long response that lacks coherence. Focus should be on content; try not to unduly penalize responses for spelling or grammar.  Keep responses between 100-150 words.
清晰简洁的答案优于缺乏连贯性的长篇大论。重点应放在内容上；尽量不对拼写或语法错误进行过度惩罚。请将回答控制在 100-150 字之间。

Step-By-Step Assignment Instructions 分步作业说明

With Module 3 looking at CAD design tools and DFAM (Design for Additive Manufacturing), you are going to develop your previous design work into a functional CAD model.  In the CAD modeling process you will need to take into account the challenges of 3D printing and what implications your choices may have. You will be asked to reflect upon questions in your submission as well as provide a link to your CAD model.
模块 3 将探讨 CAD 设计工具和 DFAM（面向增材制造的设计），你将把之前的设计工作发展成一个功能性的 CAD 模型。在 CAD 建模过程中，你需要考虑 3D 打印的挑战以及你的选择可能带来的影响。你将被要求反思提交中的问题，并提供你的 CAD 模型的链接。

You will have to deliver the following items for this assignment: 您需要为这项作业提供以下物品

A link to your CAD model in one of the following methods.
链接到您的 CAD 模型，以下任一方法均可。

1. Public link the CAD file via TinkerCAD, Fusion360, or any other published CAD file.
   通过 TinkerCAD、Fusion360 或其他任何已发布的 CAD 文件公开链接 CAD 文件。
2. Uploaded STL file to a 3D model repository such as Thingiverse, Pinshape, YouMagine, GrabCAD, or any other appropriate site as described in previous coursework.
   将 STL 文件上传到 3D 模型仓库，如 Thingiverse、Pinshape、YouMagine、GrabCAD 或其他适当网站，具体操作请参考之前的课程内容。

A written response providing details on the following questions about your design and 3D printing.
一份关于您的设计和 3D 打印的以下问题的书面回复，提供详细信息。

1. What type of material would be the best choice for this design and why is it the best choice?
   这种设计最适合的材料类型是什么，为什么它是最佳选择？
2. If you were to use an FFF (Fused Filament Fabrication) 3D printer, what size and type of nozzle would be most appropriate and why (type referring to the material the nozzle is made from)?
   如果您使用 FFF（熔融沉积成型）3D 打印机，最合适的喷嘴尺寸和类型是什么（类型指喷嘴所用的材料），为什么？
3. What kinds of post processing work would be most appropriate for this application and why is that important?
   适用于此应用的后期处理工作有哪些最合适，为什么这很重要？

Keep each response between 100-150 words and as you respond, consider the following questions to self check your work:
保持每条回复在 100-150 字之间，在回复时，考虑以下问题来自我检查你的工作：

• Does my response use appropriate technical terminology?
  我的回答是否使用了适当的技术术语？
• Is my response supported by the previous lectures and other sources you may have found?
  我的回答是否得到了之前的讲座和其他你可能找到的资料的支持？

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3x3 Lipstick Organizer

https://a360.co/3XjtLiO

PETG (Polyethylene Terephthalate Glycol) is ideal for this design. Its transparency allows users to easily identify lipstick shades, while its chemical resistance prevents degradation from cosmetic residues. PETG offers excellent layer adhesion and minimal warping compared to PLA or ABS, ensuring structural integrity for thin-walled compartments. The material’s moderate flexibility reduces brittleness, making it durable for daily use. Additionally, PETG is food-safe (when printed with a food-safe nozzle) and heat-resistant up to ~85°C, suitable for environments like bathrooms. While PLA is easier to print, it lacks PETG’s moisture resistance and thermal stability. ABS provides higher strength but requires enclosed printers to manage warping and emits harmful fumes. PETG balances aesthetics, functionality, and printability for cosmetic applications.

A 0.4mm hardened steel nozzle is optimal for this project. The 0.4mm diameter balances print speed and detail, crucial for sharp edges and smooth surfaces in small compartments. Hardened steel nozzles are durable for abrasive materials like PETG, which can wear down brass nozzles over time. While brass nozzles are cheaper, they lack longevity for repeated PETG printing. A larger nozzle (e.g., 0.6mm) would speed up printing but sacrifice fine details, while smaller nozzles (0.2mm) risk clogging with PETG’s higher viscosity. The hardened steel’s heat resistance also ensures stable extrusion at PETG’s recommended 220–245°C. For Bambu Labs printers, pairing this nozzle with their high-speed capabilities maintains precision without compromising print quality.

Key post-processing steps include sanding, chemical smoothing, and assembly checks. Light sanding (400–1000 grit) removes layer lines and enhances transparency, critical for a polished look. PETG can be vapor-smoothed with ethyl acetate (sparingly) to restore clarity without clouding. Removing support marks with flush cutters ensures a clean interior. A food-safe epoxy coating adds a glossy finish and seals micro-gaps. Ultrasonic cleaning in isopropyl alcohol eliminates dust and oils from handling. Finally, testing compartment fit with actual lipsticks ensures smooth insertion/removal. These steps improve aesthetics, hygiene, and functionality, aligning with cosmetic storage standards where appearance and cleanliness are priorities.

This is my final printed lipstick organizer. I’m thrilled with how it turned out—perfect for displaying on a vanity or storing discreetly in a drawer!