Tech-dat/tech-dat.md
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- [[off-road-dat]]
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+- [[fab-product-dat]]
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+
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## Circuits
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- [[circuits-dat]] - [[LC-circuits-dat]] - [[bias-T-dat]] - [[gain-shaping-dat]] - [[LNA-dat]] - [[74xx-dat]] - [[LMxx-dat]] - [[CDxx-dat]] - [[isolator-dat]]
fab-dat/fab-product-dat/fab-joining-dat/fab-joining-dat.md
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+
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+# fab-joining-dat
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+
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+- [[glue-dat]] - [[fab-joining-dat]] - [[fab-product-dat]]
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+
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+- [[rivet-dat]]
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+
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+- [[brazing-dat]] - [[metal-welding-dat]]
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+
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+
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+## summary
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+
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+| Method / Joint Type | Peak Tensile Strength | Primary Joining Mechanism | Best Suited For | Key Weakness |
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+| :--- | :--- | :--- | :--- | :--- |
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+| **Metal Welding** | **Absolute Maximum** ($\ge 400 \text{ MPa}$) | Co-melting & fusion of base metals | Structural steel, heavy machinery, high-pressure pipes | Extreme heat warping, difficult on dissimilar metals |
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+| **Brazing** | **Very High to Supreme** ($\ge 150 \text{ MPa}$) | Capillary action of high-temp filler | Dissimilar metals, copper pipes, radiator cores | Requires microscopic fit-up tolerances |
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+| **Riveting** | **Extremely High** ($\ge 150 \text{ MPa}$) | Mechanical interlocking & clamping | Aircraft fuselages, bridges, non-weldable alloys | Heavy, requires drilling, not naturally leak-proof |
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+| **Soldering** | **Moderate** ($\sim 50 \text{ MPa}$) | Capillary action of low-temp filler | Electronics, PCB assembly, copper plumbing | Weak mechanical load capacity |
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+| **Aviation Adhesives** | **High** ($\sim 45 \text{ MPa}$) | Advanced chemical cross-linking | Aerospace panels, modern automotive bodies | Demanding surface prep, long cure times |
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+| **AB Glue (Epoxy)** | **High (Structural)** ($\ge 30 \text{ MPa}$) | Chemical reaction polymerization | General rigid repairs, gap filling, hobbyist metal | Brittle, zero elasticity |
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+| **UV Glue** | **Extremely High** ($\ge 20 \text{ MPa}$) | Photo-initiated polymerization | Glass-to-metal, clear acrylics, rapid repairs | Requires UV light pathway to cure |
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+| **502 Glue (Super)** | **Very High** ($\sim 20 \text{ MPa}$) | Moisture-activated polymerization | Small, tight-fitting non-porous repairs | Poor impact resistance (shatters easily) |
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+| **B-7000** | **Medium** ($\sim 3 \text{ MPa}$) | Solvent evaporation (elastic polymer) | Phone screens, flexible joints, vibration damping | Low static load limit (creeps under weight) |
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+| **Hot Melt** | **Lowest** ($\sim 1 \text{ MPa}$) | Physical cooling solidification | Quick crafts, temporary holding, soft materials | Melts under mild heat, poor adhesion to metals |
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+
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+
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+## list
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+
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+* **Metal Welding: *The True Fusion Benchmark***
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+ * **Tensile Strength:** **Absolute Maximum.** Depending on the metal filler rod and base material (e.g., mild steel), welding easily achieves tensile strengths of **400 to 550+ MPa** ($58,000 \text{ to } 80,000+ \text{ psi}$).
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+ * **Behavior under load:** It does not merely stick two parts together; it melts them into a single, continuous piece of metal. The welded joint is chemically, molecularly, and physically integrated, often making the weld itself stronger than the surrounding base metal.
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+ * **Weakness:** Requires specialized machinery, intense heat, safety gear, and alters the properties of the material permanently (creates a Heat-Affected Zone).
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+
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+* **Brazing (钎焊): *The High-Strength Capillary Cousin***
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+ * **How it works:** Similar to welding, but instead of melting the base metals, you heat them just below their melting point and introduce a filler metal (typically brass, bronze, or silver alloy) with a melting point above 450°C (840°F). Capillary action draws the liquid filler into the microscopic gap between the tight-fitting parts.
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+ * **Tensile Strength:** **Very High to Supreme.** Typically **100 to 350+ MPa** ($14,500 \text{ to } 50,000+ \text{ psi}$), depending on the clearance and filler alloy.
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+ * **Pros vs. Welding:** Can easily join dissimilar metals (e.g., copper to steel) and produces highly ductile, leak-proof joints with minimal thermal distortion.
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+ * **Cons:** Requires extremely tight tolerances (gaps of 0.05 to 0.1 mm) and pristine surface cleanliness.
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+
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+* **Riveting (铆接): *The Mechanical Giant***
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+ * **How it works:** A mechanical fastening method where a metal pin (rivet) is inserted through pre-drilled holes in the overlapping sheets and then deformed (squeezed or hammered) on the other end to lock the plates together permanently.
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+ * **Tensile Strength:** **Extremely High.** Standard structural steel rivets hold shear and tensile strengths of **150 to 300+ MPa** ($21,000 \text{ to } 43,000+ \text{ psi}$).
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+ * **Pros vs. Welding:** Absolutely zero heat is introduced, meaning no thermal warping, no changes to the metal’s crystalline structure, and no risk of cracking. This is why aircraft wings and historical steel bridges (like the Golden Gate) are riveted rather than welded.
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+ * **Cons:** Adds physical weight, requires drilling holes (which can introduce stress concentration points), and is not naturally air- or water-tight without separate sealants.
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+
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+* **Soldering (软钎焊): *The Precision Electrical Bond***
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+ * **How it works:** Similar to brazing, but the filler metal (lead-free tin alloys) melts at a much lower temperature—below 450°C (typically around 180°C to 250°C).
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+ * **Tensile Strength:** **Low to Moderate.** Typically **30 to 80 MPa** ($4,300 \text{ to } 11,600 \text{ psi}$).
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+ * **Pros vs. Welding:** Very low heat, highly conductive, and easily reversible. Perfect for securing electrical components on PCBs and joining copper plumbing pipes.
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+ * **Cons:** Poor structural load capacity; cannot be relied upon to hold heavy weight or withstand severe mechanical stress.
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+
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+* **Aviation-Grade Structural Adhesives (航空级结构胶): *The Chemical Weld***
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+ * **How it works:** Specialized, high-performance polyurethanes, modified epoxies, or acrylics. They are engineered to chemically bite into the surface molecules of metals and composites.
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+ * **Tensile Strength:** **Very High (for Adhesives).** **35 to 55+ MPa** ($5,000 \text{ to } 8,000+ \text{ psi}$).
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+ * **Pros vs. Welding:** Distributes stress uniformly across the entire bonded surface area rather than focusing it at a single weld seam or rivet point. It also dampens acoustics, prevents galvanic corrosion between dissimilar metals (like carbon fiber to aluminum), and is widely used in modern hypercars and commercial jets.
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+ * **Cons:** Demanding surface preparation is required, and it requires hours to cure.
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+
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+
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+
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+## metal joining
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+
63
+在金属连接工艺中，**熔焊（Welding）**、**硬钎焊（Brazing）**和**软钎焊（Soldering）**是三种最核心的工艺。
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+
65
+它们最根本的区别可以总结为两点：**“母材（被连接的金属）熔不熔化”** 以及 **“工作温度是多少”**。
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+
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+
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+
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+---
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+
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+### 1. 核心概念拆解
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+
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+#### 1. 熔焊 (Metal Welding) —— “彻底融为一体”
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+* **原理**：通过极高的温度，将**两块母材的接触面直接熔化**，同时通常会加入熔化的焊条/焊丝，让它们在液态下混合。冷却后，两块金属在原子层面上融合成了一个整体。
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+* **温度**：极高，通常在 **1000°C 至 3000°C 以上**（必须达到母材的熔点）。
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+* **特点**：
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+ * **强度最高**：接头强度等同于、甚至超过母材本身。
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+ * **永久变形**：由于局部高温，金属容易发生热变形或产生内应力。
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+ * **无法拆卸**：一旦焊接，除非破坏金属本身，否则无法分离。
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+ * **适用场景**：钢结构、造船、汽车车架、压力容器等重工业。
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+
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+#### 2. 钎焊 / 硬钎焊 (Brazing) —— “强力胶水渗透”
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+* **原理**：**母材完全不熔化**。将母材加热到低于其熔点、但高于钎料熔点的温度。把熔点较低的“钎料”（如铜合金、银合金）熔化，利用**毛细管作用**让液态钎料自动吸入两块母材之间极小的缝隙中，冷却后实现连接。
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+* **温度**：中高，定义在 **450°C 以上**（通常在 600°C 至 900°C 之间），但必须低于母材熔点。
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+* **特点**：
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+ * **异种金属连接**：可以完美连接两种完全不同的金属（如铜和铁、硬质合金和钢）。
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+ * **变形极小**：因为不需要熔化母材，整体受热均匀，精密零件不易变形。
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+ * **接头美观**：焊缝极其平整、光滑。
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+ * **适用场景**：自行车车架、冰箱空调的铜管连接、高档刀具镶齿、航空精密零部件。
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+
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+#### 3. 软钎焊 / 锡焊 (Soldering) —— “精密导电连接”
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+* **原理**：与硬钎焊（Brazing）的原理完全相同（**母材不熔化**，靠毛细管作用填充缝隙），唯一的区别在于**使用的焊料熔点较低**，最常用的焊料是锡基合金（俗称焊锡）。
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+* **温度**：较低，定义在 **450°C 以下**（通常在 180°C 至 300°C 之间）。
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+* **特点**：
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+ * **热影响极小**：极低的温度不会损坏敏感的电子元器件。
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+ * **导电性极佳**：主要用于建立电气连接，而不是为了承受重载。
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+ * **易于拆卸**：用烙铁重新加热即可熔化焊锡，轻松拆卸和维修。
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+ * **适用场景**：电子电路板（PCB）组装、芯片焊接、精细珠宝加工、铜管管道连接（水管）。
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+
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+---
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+
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+### 2. 核心区别直观对比表
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+
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+| 特性 | 熔焊 (Welding) | 钎焊 / 硬钎焊 (Brazing) | 软钎焊 / 锡焊 (Soldering) |
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+| :--- | :--- | :--- | :--- |
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+| **母材是否熔化** | **是** (完全熔化) | **否** (保持固体状态) | **否** (保持固体状态) |
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+| **工作温度** | **极高** (高于母材熔点，>1000°C) | **中高** (高于450°C，低于母材熔点) | **较低** (低于450°C，通常180°C - 300°C) |
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+| **常用填充材料** | 钢、铝、不锈钢等焊条/焊丝 | 铜合金、银合金、铝硅合金等 | 锡铅合金、无铅锡银铜合金 (焊锡) |
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+| **接头强度** | **极高** (等同或超过母材) | **高** (可承受相当大的压力/拉力) | **低** (主要用于导电或密封，不承重) |
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+| **装配间隙要求**| 无严格要求，可填大缝 | **极严格** (通常要求 0.05 - 0.1 mm) | **严格** (依靠毛细管吸入) |
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+| **热变形程度** | **严重** (局部高温易变形) | **微小** (整体或局部中温，变形小) | **极微** (不损坏电子元件) |
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+| **主要应用** | 重工业、建筑、管道、钢结构 | 暖通铜管、刀具、异种金属连接 | 电子电路板、电器维修、精密仪器 |
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+
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+---
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+
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+> **💡 一句话总结记忆法：**
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+> * **熔焊**：把两块金属的边缘直接烧化捏成一坨，力大砖飞，强度最高。
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+> * **硬钎焊**：用高温把“硬铜/银”熔成液体，吸进两块不熔化的金属缝里，适合精密异种金属连接。
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+> * **软钎焊**：用低温烙铁把“锡”熔化，把电子元件粘在电路板上，主打导电和好拆卸。
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+
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+
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+## ref
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+
fab-dat/fab-product-dat/fab-product-dat.md
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# fab-product-dat
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+- [[fab-joining-dat]] - [[rivet-dat]] - [[fab-product-dat]] - [[bracket-dat]]
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- [[fab-bending-dat]] - [[fab-product-dat]]
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... ...
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- [[fab-mechanics-dat]]
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+
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+
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## small scale and prototype preparation
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- [[fab-drilling-dat]]
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## ref
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-- [[fab-dat]]
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\ No newline at end of file
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+- [[fab-dat]]
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+
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+- [[fab-product]] - [[fab]]
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\ No newline at end of file
fab-mechanics-dat/glue-dat/B-7000-dat/B-7000-dat.md
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+
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+
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+# B-7000-dat
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+
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+- [[glue-TPE-dat]] - [[B-7000-dat]] - [[glue-dat]]
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+
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+
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+
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+**B-7000** is a highly popular, professional-grade **multipurpose contact adhesive** widely known for its precision, elasticity, and strong bonding capabilities.
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+
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+If you have ever had a smartphone screen replaced, or if you do a lot of DIY electronics, jewelry making, or crafting, you have likely encountered B-7000. It is often considered a staple in the repair industry.
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+
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+---
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+
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+### 1. Key Characteristics of B-7000
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+
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+* **Medium Viscosity & Self-Leveling:** It has a semi-fluid, gel-like consistency. It flows easily enough to self-level and fill small gaps but is thick enough not to run uncontrollably.
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+* **Rubber-Like Elasticity:** Unlike superglue (cyanoacrylate), which dries hard and brittle, B-7000 cures into a **flexible, rubbery state**. This makes it highly resistant to vibrations, impacts, and daily wear-and-tear—a must-have property for mobile devices that are constantly moved or dropped.
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+* **Built-In Precision Needle Nozzle:** B-7000 tubes are famous for having a built-in, ultra-fine metal nozzle in the cap. This allows you to apply microscopic beads of glue directly into tight seams (like phone bezels) without messy spilling.
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+* **Slow Curing (Room Temperature):**
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+ * **Tack/Surface Dry:** 3 to 6 minutes. This gives you a brief window to reposition your parts.
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+ * **Full Cure:** 24 to 48 hours. It requires clamping or light pressure during the initial phase for the strongest bond.
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+* **Waterproof & Removable with Heat:** Once fully cured, B-7000 is completely waterproof. Crucially for electronics, **it can be softened with a heat gun** (at around 80°C), allowing you to open a repaired device again in the future without damaging the components.
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+
25
+---
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+
27
+### 2. Common Applications
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+
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+Because it bonds incredibly well to both porous and non-porous surfaces, it is highly versatile:
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+
31
+* **Electronics Repair:** Re-attaching phone screens (LCDs), digitizers, back glass covers, tablet bezels, and protecting soldered joints.
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+* **Jewelry & Crafts:** Securing small rhinestones, beads, gems, and metal backings to fabric, leather, or plastic.
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+* **DIY Hardware:** Mounting small plastic or rubber brackets, sealing micro-gaps against moisture, or securing loose wires/cables in low-heat areas.
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+
35
+---
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+
37
+### 3. Quick Comparison: B-7000 vs. UV Glue vs. Hot Melt
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+
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+To connect this to what we discussed earlier, here is how B-7000 sits in the adhesive landscape:
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+
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+| Feature | B-7000 Glue | UV (Light-Curing) Glue | Hot Melt Glue |
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+| :--- | :--- | :--- | :--- |
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+| **Curing Mechanism** | Solvent evaporation | UV light chemical reaction | Physical cooling |
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+| **Flexibility** | **Very High** (rubbery, dampens vibration) | Low to Medium (tends to be rigid) | High (but bulky) |
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+| **Material Limit** | Works on almost anything (opaque or clear) | At least one side must be transparent | Works on most surfaces |
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+| **Reversibility** | **Easy** (softens with mild heat) | Difficult (usually requires scraping/chemicals) | Easy (re-melts with heat) |
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+| **Best For** | Phone screens, jewelry, flexible joints | Instant rigid bonding, glass-on-glass | Quick, heavy-duty gap filling |
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+
49
+---
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+
51
+> **⚠️ The Main Limitation:**
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+> UV glue **must be exposed to UV light** to cure. If you are bonding two completely opaque metal blocks together where the light cannot penetrate, the glue inside will remain liquid. In such cases, hot melt glue or epoxy (AB glue) would be more suitable.
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+
54
+
55
+### Mechanical Strength Summary
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+
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+| Glue Type | Peak Tensile Strength | Load Type Best Suited For | Failure Mode |
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+| :--- | :--- | :--- | :--- |
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+| **UV Glue** | **Highest** ($\ge 20 \text{ MPa}$) | Heavy, static compression & rigid pull | Brittle snapping / Substrate fracture |
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+| **B-7000** | **Medium** ($\sim 3 \text{ MPa}$) | Constant vibration, impact, flexing & peeling | Slow stretching / Elastic deformation |
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+| **Hot Melt** | **Lowest** ($\sim 1 \text{ MPa}$) | Light decorative duty, temporary clamping | Clean peeling / Interfacial delamination |
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+
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+
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+
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+## ref
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\ No newline at end of file
fab-mechanics-dat/glue-dat/glue-UV-dat/glue-UV-dat.md
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- [[glue-hot-dat]] - [[glue-UV-dat]] - [[glue-dat]] - [[cable-dat]] - [[installation-dat]]
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+
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+## Compared to hot melt adhesive
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+
10
+Compared to hot melt adhesive, **light-curing adhesive (commonly referred to as UV glue)** offers decisive advantages in terms of **precision, strength, and operational control**.
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+
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+Here is a breakdown of why light-curing adhesive outperforms hot melt glue in many scenarios:
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+
14
+---
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+
16
+### 1. Key Advantages
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+
18
+* **Total Control: No Light, No Curing**
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+ * **Hot Melt Glue**: Once extruded from the glue gun, it cools and solidifies within seconds. You have to act extremely fast, and there is almost no room for micro-adjustments if things go misaligned.
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+ * **UV Glue**: It remains in a liquid state indefinitely until exposed to ultraviolet (UV) light. You can take your time to perfectly position the parts and wipe away any excess glue. Once everything is flawless, a few seconds under a UV light will instantly cure it.
21
+* **Micron-Level Precision**
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+ * **Hot Melt Glue**: The adhesive is thick and leaves a bulky, rubbery layer after curing.
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+ * **UV Glue**: It has excellent fluidity, allowing it to penetrate micro-gaps. The cured layer can be as thin as a few microns, making it essential for precision electronics, lenses, or delicate figure repairs.
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+* **Invisible Aesthetics & No Stringing**
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+ * **Hot Melt Glue**: It is notorious for "stringing" (creating messy spiderweb-like threads) and cures into an opaque or semi-transparent blob, which can look messy.
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+ * **UV Glue**: It cures to a crystal-clear finish, achieving virtually seamless bonding. It is perfect for glass, acrylic, and other transparent materials.
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+* **Superior Temperature Resistance & Strength**
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+ * **Hot Melt Glue**: It relies on physical curing (melting via heat, solidifying via cooling). This means it is **not heat-resistant**. If exposed to high temperatures (e.g., inside a car on a hot summer day or near a hot microchip), it will soften or melt again.
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+ * **UV Glue**: It triggers a photochemical reaction that creates strong chemical cross-links. Once cured, it boasts exceptional bond strength and high temperature resistance—it will not re-melt.
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+
31
+---
32
+
33
+### 2. Side-by-Side Comparison
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+
35
+| Feature | Light-Curing Adhesive (UV Glue) | Hot Melt Glue |
36
+| :--- | :--- | :--- |
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+| **Curing Mechanism** | UV Light Chemical Reaction | Physical Cooling & Solidification |
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+| **Adjustment Time** | Unlimited (until UV light is applied) | Very Short (seconds to tens of seconds) |
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+| **Layer Thickness** | Ultra-thin, high precision | Thick, better for gap filling |
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+| **Appearance** | Highly transparent, no trace, no stringing | Semi-transparent/White, prone to stringing |
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+| **Thermal Resistance** | Excellent (won't degrade under heat) | Poor (re-melts easily when heated) |
42
+| **Bond Strength** | High (structural grade bonding) | Moderate (easy to peel off) |
43
+| **Material Limit** | At least one side must be transparent | Works on most materials (opaque is fine) |
44
+
45
+---
46
+
47
+> **⚠️ The Main Limitation:**
48
+> UV glue **must be exposed to UV light** to cure. If you are bonding two completely opaque metal blocks together where the light cannot penetrate, the glue inside will remain liquid. In such cases, hot melt glue or epoxy (AB glue) would be more suitable.
49
+
50
+## info
51
+
7 52
fix in least down to 5 seconds
8 53
9 54
![](2026-06-25-13-30-47.png)
fab-mechanics-dat/glue-dat/glue-dat.md
... ...
@@ -13,21 +13,40 @@
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14 14
- [[adhesive-remover-dat]]
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-# 🔍 Comparison of Adhesives
16
+- [[glue-TPE-dat]] - [[B-7000-dat]] - [[glue-dat]]
17 17
18
-| Feature / Property | 502 Glue (Cyanoacrylate) | Epoxy Resin (AB Glue) | Hot Glue (Thermoplastic) | UV Glue (Light-Cured Adhesive) |
19
-|---------------------------|-------------------------------|-----------------------------------|----------------------------------|-------------------------------------|
20
-| **Main Component** | Cyanoacrylate | Epoxy resin + Hardener | Thermoplastic (EVA) | Acrylated resin + photoinitiators |
21
-| **Curing Trigger** | Moisture (in air/surface) | Chemical (resin + hardener mix) | Heat (glue gun) | UV light |
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-| **Cure Time** | Seconds | Minutes to hours | Seconds (cools fast) | Seconds (with UV light) |
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-| **Bond Strength** | High | Very High | Medium | High |
24
-| **Material Compatibility**| Metal, plastic, rubber, etc. | Most surfaces | Most porous and some plastics | Glass, plastic, metal |
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-| **Heat Resistance** | Low to Moderate | High | Low | Moderate to High |
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-| **Moisture Resistance** | Moderate | High | Low | High |
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-| **Application Control** | Moderate (can drip) | Requires mixing, precise | Easy, but can be stringy | Precise (controlled by light) |
28
-| **Reusability** | No (one-time bond) | No (once mixed, must be used) | Yes (reheat and reuse) | No |
29
-| **Common Uses** | Quick household repairs, models| Heavy-duty bonding, structural | Crafts, packaging, quick fixes | Phone screens, jewelry, precision |
30
-| **Cleanup** | Acetone | Alcohol/solvents before cure | Peel off | Alcohol or acetone |
18
+- [[glue-Aviation-Adhesive-dat]]
19
+
20
+## Mechanical Strength Summary
21
+
22
+- [[fab-product-dat]]
23
+
24
+| Joint / Glue Type | Peak Tensile Strength | Load Type Best Suited For | Failure Mode | Flexibility vs. Brittleness |
25
+| :---------------- | :---------------------------------------------- | :--------------------------------------------------- | :--------------------------------------- | :-------------------------- |
26
+| **Metal Welding** | **Absolute Maximum** ($\ge 400 \text{ MPa}$) | Heavy machinery, infrastructure, structural steel | Material yield / Base metal tearing | Rigid (Same as host metal) |
27
+| **AB Glue** | **Highest (Structural)** ($\ge 30 \text{ MPa}$) | Industrial loads, metal/ceramic repair, deep gaps | Substrate fracture / Rare shearing | Rigid & Rock-Hard |
28
+| **UV Glue** | **Extremely High** ($\ge 20 \text{ MPa}$) | Heavy, static compression & rigid pull (Clear parts) | Brittle snapping / Substrate fracture | Rigid |
29
+| **502 Glue** | **Very High** ($\sim 20 \text{ MPa}$) | Tight-fitting, rigid joints with direct pull | Sudden shattering under impact | Extremely Brittle |
30
+| **B-7000** | **Medium** ($\sim 3 \text{ MPa}$) | Constant vibration, impact, flexing & peeling | Slow stretching / Elastic deformation | Highly Flexible (Rubbery) |
31
+| **Hot Melt** | **Lowest** ($\sim 1 \text{ MPa}$) | Light decorative duty, temporary clamping | Clean peeling / Interfacial delamination | Semi-Flexible (Gummy) |
32
+
33
+
34
+
35
+## 🔍 Comparison of Adhesives
36
+
37
+| Feature / Property | 502 Glue (Cyanoacrylate) | Epoxy Resin (AB Glue) | Hot Glue (Thermoplastic) | UV Glue (Light-Cured Adhesive) |
38
+| -------------------------- | ------------------------------- | ------------------------------- | ------------------------------ | --------------------------------- |
39
+| **Main Component** | Cyanoacrylate | Epoxy resin + Hardener | Thermoplastic (EVA) | Acrylated resin + photoinitiators |
40
+| **Curing Trigger** | Moisture (in air/surface) | Chemical (resin + hardener mix) | Heat (glue gun) | UV light |
41
+| **Cure Time** | Seconds | Minutes to hours | Seconds (cools fast) | Seconds (with UV light) |
42
+| **Bond Strength** | High | Very High | Medium | High |
43
+| **Material Compatibility** | Metal, plastic, rubber, etc. | Most surfaces | Most porous and some plastics | Glass, plastic, metal |
44
+| **Heat Resistance** | Low to Moderate | High | Low | Moderate to High |
45
+| **Moisture Resistance** | Moderate | High | Low | High |
46
+| **Application Control** | Moderate (can drip) | Requires mixing, precise | Easy, but can be stringy | Precise (controlled by light) |
47
+| **Reusability** | No (one-time bond) | No (once mixed, must be used) | Yes (reheat and reuse) | No |
48
+| **Common Uses** | Quick household repairs, models | Heavy-duty bonding, structural | Crafts, packaging, quick fixes | Phone screens, jewelry, precision |
49
+| **Cleanup** | Acetone | Alcohol/solvents before cure | Peel off | Alcohol or acetone |
31 50
32 51
33 52
... ...
@@ -107,14 +126,14 @@ FDM 3D prints have tiny gaps and a layered structure:
107 126
### 4. **Incompatible Materials**
108 127
Some common filaments are just not suitable for cyanoacrylate:
109 128
110
-| Material | 502 Glue Compatibility |
111
-|----------------|------------------------|
112
-| PLA | ✅ Generally bonds well |
113
-| ABS | ⚠️ Moderate (may need sanding) |
114
-| PETG | ⚠️ Difficult, slippery surface |
115
-| TPU / TPE | ❌ Very poor bonding (flexible) |
116
-| Nylon | ❌ Very difficult to bond |
117
-| PP / PE | ❌ Extremely poor adhesion |
129
+| Material | 502 Glue Compatibility |
130
+| --------- | ------------------------------ |
131
+| PLA | ✅ Generally bonds well |
132
+| ABS | ⚠️ Moderate (may need sanding) |
133
+| PETG | ⚠️ Difficult, slippery surface |
134
+| TPU / TPE | ❌ Very poor bonding (flexible) |
135
+| Nylon | ❌ Very difficult to bond |
136
+| PP / PE | ❌ Extremely poor adhesion |
118 137
119 138
### 5. **Oily or Contaminated Surface**
120 139
Some filaments (like PETG or nylon) may feel **greasy** or attract **oil/dust**, which prevents proper glue bonding.
... ...
@@ -131,12 +150,12 @@ Some filaments (like PETG or nylon) may feel **greasy** or attract **oil/dust**,
131 150
132 151
## For high-strength bonding of mechanical transmission components (e.g., gears, bearings, linkages, metal or hard plastic parts), the recommended adhesives are:
133 152
134
-| Adhesive Type | Suitable Materials | Features & Recommendations |
135
-|----------------------------|-----------------------------------|----------------------------------------------------------------------------|
136
-| AB Glue (Epoxy Resin, 2-part) | Metal, ceramics, hard plastics, composites | Extremely strong, gap-filling, rigid after curing, heat and chemical resistant, good for shear and pressure loads |
137
-| MMA Adhesive (Methyl Methacrylate) | Metal, composites, hard plastics | Industrial-grade, strong and slightly flexible, vibration-resistant, suitable for high-speed or vibrating environments |
138
-| Structural Acrylic Adhesive | Metal-to-metal, composites | High shear strength, commonly used in automotive or mechanical structural parts |
139
-| PU Adhesive (Polyurethane Structural Glue) | Metal, hard plastic, composites | Flexible, absorbs vibration, good for impact or minor vibration, slightly lower strength than AB glue |
153
+| Adhesive Type | Suitable Materials | Features & Recommendations |
154
+| ------------------------------------------ | ------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------- |
155
+| AB Glue (Epoxy Resin, 2-part) | Metal, ceramics, hard plastics, composites | Extremely strong, gap-filling, rigid after curing, heat and chemical resistant, good for shear and pressure loads |
156
+| MMA Adhesive (Methyl Methacrylate) | Metal, composites, hard plastics | Industrial-grade, strong and slightly flexible, vibration-resistant, suitable for high-speed or vibrating environments |
157
+| Structural Acrylic Adhesive | Metal-to-metal, composites | High shear strength, commonly used in automotive or mechanical structural parts |
158
+| PU Adhesive (Polyurethane Structural Glue) | Metal, hard plastic, composites | Flexible, absorbs vibration, good for impact or minor vibration, slightly lower strength than AB glue |
140 159
141 160
⚙️ **Selection Recommendations**:
142 161
1. **High load, requires rigidity** → **AB Glue (Epoxy Resin)**
fab-mechanics-dat/glue-dat/glue-epoxy-dat/glue-epoxy-dat.md
... ...
@@ -0,0 +1,21 @@
1
+
2
+# epoxy-glue-dat.md
3
+
4
+epoxy glue is commonly referred to as AB glue.
5
+
6
+三、推荐的具体胶水（常见好买）
7
+✅ 性价比方案（可 DIY）
8
+
9
+慢固化 AB 胶（24 小时型）
10
+
11
+比如：工业级环氧胶、EPOXY ADHESIVE
12
+
13
+强度明显高于 5 分钟胶
14
+
15
+⭐ 更稳的工程方案
16
+
17
+3M DP420 / DP460（环氧结构胶）
18
+
19
+Loctite EA 9460 / 9480
20
+
21
+Loctite 330（配底涂）（丙烯酸）
... ...
\ No newline at end of file
fab-mechanics-dat/glue-dat/glue-expory-dat/glue-expory-dat.md
... ...
@@ -1,21 +0,0 @@
1
-
2
-# epoxy-glue-dat.md
3
-
4
-epoxy glue is commonly referred to as AB glue.
5
-
6
-三、推荐的具体胶水（常见好买）
7
-✅ 性价比方案（可 DIY）
8
-
9
-慢固化 AB 胶（24 小时型）
10
-
11
-比如：工业级环氧胶、EPOXY ADHESIVE
12
-
13
-强度明显高于 5 分钟胶
14
-
15
-⭐ 更稳的工程方案
16
-
17
-3M DP420 / DP460（环氧结构胶）
18
-
19
-Loctite EA 9460 / 9480
20
-
21
-Loctite 330（配底涂）（丙烯酸）
... ...
\ No newline at end of file
fab-mechanics-dat/mechanical-parts-dat/bracket-dat/bracket-dat.md
... ...
@@ -1,6 +1,7 @@
1 1
2 2
# bracket-dat
3 3
4
+- [[rivet-nut-dat]] - [[bracket-dat]] - [[rivet-dat]]
4 5
5 6
- [[bracket-dat]] - [[bracket-l-dat]]
6 7
fab-mechanics-dat/mechanical-structure-dat/Rivet-dat/Rivet-dat.md
... ...
@@ -1,7 +1,70 @@
1 1
2 2
# Rivet-dat
3 3
4
-- [[rivet-nut-dat]]
4
+- [[rivet-nut-dat]] - [[bracket-dat]] - [[rivet-dat]]
5
+
6
+- [[fab-joining-dat]] - [[rivet-dat]] - [[fab-product-dat]]
7
+
8
+- [[mechanical-structure-dat]]
9
+
10
+## Connecting Round Tubes Perpendicularly Using Rivets
11
+
12
+**Yes, it is absolutely possible!** However, because round tubes have curved surfaces, trying to rivet them directly face-to-face will result in an unstable joint that wobbles, and the rivets will easily loosen over time.
13
+
14
+To create a rock-solid, professional-grade perpendicular joint using rivets, you should use one of the following three proven engineering methods:
15
+
16
+---
17
+
18
+#### Method 1: The Internal T-Connector Method (Highly Recommended)
19
+
20
+This is the most common method used in commercial products like outdoor tents, display racks, and lightweight aluminum frames. It is highly structural and aesthetically clean.
21
+
22
+
23
+
24
+* **How to do it:**
25
+ 1. Obtain an **internal T-connector** (made of nylon, plastic, or aluminum) that matches the inner diameter (ID) of your tubes.
26
+ 2. Insert the connector into the ends of the tubes to join them perpendicularly.
27
+ 3. Drill pilot holes through the outer tube wall and into the connector.
28
+ 4. Insert and pop-rivet them together.
29
+* **Pros:** The rivet clamps against a solid internal insert, preventing the thin-walled tube from crushing. Highly stable and visually seamless.
30
+
31
+---
32
+
33
+#### Method 2: Coped Joint (Fishmouth Cut) + Saddle Washer Method
34
+
35
+If you want the two metal tubes to touch directly without using internal plastic or nylon fittings, you must contour the intersecting tube.
36
+
37
+当你把垂直管切出鱼嘴口并贴在横管上时，垂直管的末端会形成两个“耳朵”（即贴合在横管外侧的弧形管壁）。
38
+
39
+* **How to do it:**
40
+ 1. **Cut a "Fishmouth" (Coping):** Profile the end of the perpendicular tube into a curved, concave shape (called a fishmouth or coped cut) so it perfectly cradles the radius of the receiving tube.
41
+ 2. **Use a Saddle Washer:** Since a standard flat rivet head cannot sit flush on a curved tube, you must place a curved **saddle washer** (also known as an arc washer) over the hole.
42
+ 3. **Rivet:** Use a blind pop rivet to fasten through the saddle washer, the first tube, and into the wall of the second tube.
43
+* **Pros:** Pure metal-to-metal contact with no external plastic parts.
44
+* **Cons:** Cutting a perfect fishmouth joint requires a tubing notched/coper tool, or careful grinding by hand.
45
+
46
+---
47
+
48
+#### Method 3: The External Split-Clamp Method (Best for Heavy-Duty)
49
+
50
+This method relies on an external metal clamp or bracket to wrap around the intersection, which is then riveted in place.
51
+
52
+
53
+
54
+* **How to do it:**
55
+ 1. Get a **two-piece perpendicular pipe clamp** (also called a split-tee clamp or saddle bracket).
56
+ 2. Clamp the bracket halves around the T-junction of the two pipes.
57
+ 3. Drill through the pre-made holes on the bracket straight into the pipe walls, then secure them with heavy-duty pop rivets.
58
+* **Pros:** Excellent load-bearing capacity; zero tube-cutting or profiling required.
59
+* **Cons:** Bulky and industrially rugged appearance; not suitable for sleek or compact designs.
60
+
61
+---
62
+
63
+### 💡 Pro Tips & Common Pitfalls
64
+
65
+1. **Never Use Flat Washers on Curvatures:** Attempting to flatten a standard washer over a round tube with a rivet gun will simply crush and dent thin-walled tubing, making the joint loose and weak.
66
+2. **Always Use Pop (Blind) Rivets:** Since you cannot access the inside of the tubes to hold a bucking bar or a nut, **blind pop rivets** are mandatory because they expand and lock from the outside.
67
+3. **Mind the Tube Wall Thickness:** If your tube wall is very thin (under $1.5 \text{ mm}$), rivets can easily tear out under stress. In these cases, **Method 1 (Internal T-Connector)** is highly recommended to distribute the load.
5 68
6 69
7 70
... ...
@@ -99,3 +162,4 @@ Place **washers** or a **spacer** between the two plates, then rivet through the
99 162
👉 This is the **recommended** method for precise rotation.
100 163
101 164
165
+## ref
... ...
\ No newline at end of file
fab-mechanics-dat/mechanical-structure-dat/mechanical-structure-dat.md
... ...
@@ -30,6 +30,8 @@ common structure: - [[sheet-dat]] - [[frame-profile-dat]] - [[shell-case-dat/she
30 30
31 31
- [[fixture-dat]]
32 32
33
+- [[rivet-dat]]
34
+
33 35
34 36
### turnover box
35 37
... ...
@@ -37,4 +39,6 @@ common structure: - [[sheet-dat]] - [[frame-profile-dat]] - [[shell-case-dat/she
37 39
38 40
## ref
39 41
40
-- [[fab-mechanics-dat]]
... ...
\ No newline at end of file
0
+- [[fab-mechanics-dat]]
1
+
2
+- [[mechanical-structure]]
... ...
\ No newline at end of file
fab-mechanics-dat/mechanical-structure-dat/structure-Composite-dat/structure-Composite-dat.md
... ...
@@ -0,0 +1,12 @@
1
+
2
+
3
+# structure-Composite-dat
4
+
5
+- [[structure-Composite-dat]]
6
+
7
+- [[tube-dat]] - [[bracket-dat]] - [[rivet-dat]] - [[tube-dat]]
8
+
9
+
10
+
11
+## ref
12
+