fab-dat/fab-PCB-soldering-dat/PCB-soldering-dross-dat/PCB-soldering-dross-dat.md
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+# PCB Solder Dross Data
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+- [[PCB-soldering-dross-dat]] - [[fab-PCB-soldering-dat]] - [[solder-paste-dat]]
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-# PCB-soldering-dross-dat
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+## 1. Introduction to Solder Dross
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-In the context of PCB soldering, the professional term for 锡渣 (xī zhā) is Solder Dross.
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+In the context of PCB soldering, the professional term for **锡渣 (xī zhā)** is **Solder Dross**. While terms like "solder scrap" or "waste solder" are used casually, "dross" is the technical standard in manufacturing.
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-While you might hear "solder scrap" or "waste solder" in casual conversation, "dross" is the specific technical term used in manufacturing and engineering.
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+### What is Solder Dross?
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+Dross is a combination of oxidized metal and impurities that forms on the surface of molten solder, particularly during wave or selective soldering. When liquid solder is exposed to air, it reacts with oxygen to create a crusty layer of metal oxides (mostly tin and lead oxides).
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-
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-### What exactly is Solder Dross?
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-
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-Dross is a combination of oxidized metal and impurities that forms on the surface of molten solder, particularly during wave soldering or selective soldering processes. When the liquid solder is exposed to air, it reacts with oxygen to create a thick, crusty layer of metal oxides (mostly tin and lead oxides).
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-
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-
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-### Key Terminology Comparison
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+### Technical Terminology Comparison
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| Chinese Term | English Technical Term | Description |
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| :--- | :--- | :--- |
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-| **锡渣** | **Solder Dross** | The oxidized "scum" that floats on top of a solder pot. |
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-| **锡球 / 锡珠** | **Solder Ball / Solder Bead** | Small, unwanted spheres of solder that stick to the PCB surface. |
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-| **锡桥** | **Solder Bridge** | An accidental connection between two conductors (a short circuit). |
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-| **焊坝** | **Solder Dam** | A barrier (often solder mask) used to prevent solder from flowing where it shouldn't. |
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+| **锡渣** | **Solder Dross** | The oxidized "scum" floating on a solder pot. |
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+| **锡球 / 锡珠** | **Solder Ball / Solder Bead** | Unwanted spheres of solder sticking to the PCB. |
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+| **锡桥** | **Solder Bridge** | Accidental short circuit between two conductors. |
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+| **焊坝** | **Solder Dam** | Physical barrier (e.g., solder mask) to control flow. |
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---
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-### Why it matters in production
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-In a professional setting, dross is managed carefully because:
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-1. **Waste:** It consumes expensive solder alloy that could otherwise be used for joints.
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-2. **Defects:** If dross particles get trapped in a solder joint, they can cause physical weakness or poor electrical conductivity.
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-3. **Maintenance:** It must be regularly skimmed off the top of the solder pot. Many factories use "dross reducers" (chemical powders) or nitrogen-inert environments to minimize its formation.
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-
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-
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-
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-## common hobby level solutions
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+## 2. Professional Prevention & Management
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+To prevent dross, you must address the root cause: **Oxidation**.
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-Markdown
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-### Reducing Solder Dross in Non-Professional Reflow Soldering
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+### Atmosphere & Chemical Control
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+* **Nitrogen ($N_2$) Blanketing:** The gold standard. Filling machines with high-purity $N_2$ (99.99%) prevents the metal from reacting with oxygen.
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+* **Dross Reducers:** Antioxidant powders (phosphorus-based pellets) or "solder oils" added to the pot to create a physical barrier against air.
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-For DIY enthusiasts or users using **non-professional equipment** (such as converted toaster ovens, hot plates, or heat guns), the "dross" or residue you see is usually caused by solder paste oxidation, flux charring, or poor temperature control.
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-
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-Here is how to minimize these issues in a home or lab environment:
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+### Process Optimization
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+* **Reduce Turbulence:** Splashing and ripples increase the surface area exposed to air. Keep pump speeds steady and wave height as low as possible.
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+* **Equipment Settings:** Use "Standby Mode" to lower pump speeds when no PCBs are on the conveyor. Keep the solder pot full to minimize the "fall" distance of returning metal.
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+* **Low-Drossing Alloys:** Use professional bars (SAC305, Sn63Pb37) that include "oxygen scavengers" like trace Germanium (Ge).
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+* **Mechanical Recovery:** Use a recovery press to squeeze good metal (usually 70-90%) out of raw dross.
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---
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-### 1. Solder Paste Management (The Source)
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-In SMT reflow, dross-like particles are often "solder balls" caused by degraded paste.
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-* **Avoid Oxidation:** Solder paste has a shelf life. Once the flux dries out, the microscopic metal powder oxidizes. When heated, these powder grains won't fuse, creating a "sand-like" dross.
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-* **Proper Warming:** If stored in a fridge, let the paste reach room temperature for 2-4 hours before opening. Using cold paste causes moisture to condense, leading to "spattering" and tiny solder beads during heating.
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-
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-### 2. Optimize the Temperature Profile
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-Non-professional tools often heat too fast or stay at peak temperature too long.
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-* **The Soak Phase:** Do not rush to the melting point. Maintain a temperature around **150°C** for 60-90 seconds. This allows the flux to clean the metal surfaces and prevents the "popcorn effect."
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-* **Limit Peak Time:** Once the solder melts (approx. 217°C for lead-free), try to finish the reflow and start cooling within 30-60 seconds. Staying at high heat for too long burns the flux into a black, crusty residue.
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+## 3. Hobby & DIY Solutions (Reflow/SMT)
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-### 3. Use High-Quality External Flux
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-If your solder joints look dull or have "scum" on top:
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-* **Add Tacky Flux:** Apply a small amount of high-quality flux (like NC-559 or similar) to the pads before reflow.
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-* **The Benefit:** Extra flux helps reduce any oxides that form during the uneven heating of a DIY oven, helping the liquid metal pull together into a clean, shiny joint.
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+In DIY reflow (toaster ovens, hot plates), "dross" is often the grey residue from oxidized paste or charred flux.
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-### 4. Stencil & Deposition Control
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-"Dross" in SMT is often just excess solder that had nowhere to go.
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-* **Use a Stencil:** Avoid hand-applying paste if possible. A stencil ensures the exact volume is applied.
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-* **Reduce Apertures:** If you consistently see tiny beads around components, design your stencil openings to be about 90% of the actual pad size.
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-
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-### 5. Environment & Cleaning
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-* **Minimize Airflow:** In a DIY toaster oven, try to keep the door closed and seal major gaps. Constant fresh air brings in more oxygen, which accelerates dross formation.
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-* **Pre-Cleaning:** Use 99.9% Isopropyl Alcohol (IPA) to clean the PCB and component leads before soldering. Contaminants like finger oils often turn into "dross" under heat.
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-
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----
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+### Best Practices for DIY
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+1. **Optimize the Profile:** Use a **"Soak Phase"** (~150°C for 60-90s) to allow flux to clean surfaces. Limit **Peak Time** (217°C+) to 30-60s to avoid burning flux into a black crust.
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+2. **Add External Flux:** Applying high-quality tacky flux (e.g., NC-559) helps reduce oxides formed by uneven heating, resulting in shiny joints.
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+3. **Stencil Precision:** Use a stencil to control volume. If beads persist, reduce stencil apertures to 90% of the pad size.
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+4. **Board Prep:** Clean the PCB with 99.9% IPA before soldering. Finger oils and contaminants often turn into "dross" under heat.
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### Troubleshooting Table
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| Symptom | Primary Cause | Solution |
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| :--- | :--- | :--- |
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-| **Solder Beads (Scattered dots)** | Rapid heating or moisture | Increase "soak" time at 150°C |
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-| **Charred Residue (Black crust)** | Temperature too high/too long | Lower peak temp; shorten reflow time |
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-| **Dull/Grainy Joints** | High oxidation | Use fresh paste; add extra flux |
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-
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-> **Pro Tip:** If using a **Hot Plate**, placing a small metal "tent" or cover over the PCB can help stabilize the temperature and create a micro-environment with less oxygen movement, resulting in much cleaner solder joints.
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-
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+| **Solder Beads** | Rapid heating or moisture | Increase "soak" time at 150°C. |
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+| **Charred Residue** | Temperature too high/long | Lower peak temp/shorten time. |
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+| **Dull/Grainy Joints** | High oxidation | Use fresh paste; add extra flux. |
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+---
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-## pressfional methods to prevent solder dross
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-
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-
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-To prevent **Solder Dross** (锡渣) in a professional SMT (Surface Mount Technology) or through-hole environment, you must address the root cause: **Oxidation**.
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-
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-Dross forms when molten solder reacts with oxygen. In a standard SMT reflow process (using solder paste), dross is less of a concern than in **Wave Soldering** or **Selective Soldering**, where large pots of molten metal are exposed to air.
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-
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-Here are the professional methods to prevent and manage dross:
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-
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-### 1. Atmosphere Control (The Gold Standard)
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-The most effective way to prevent dross is to remove the oxygen entirely.
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-* **Nitrogen ($N_2$) Blanketing:** Filling the soldering machine with high-purity Nitrogen (typically 99.99% or oxygen levels below 500 ppm). Without oxygen, the metal cannot oxidize into dross.
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-* **Inerting the Wave:** In wave soldering, specialized "hoods" or nitrogen diffusers cover the solder pot to keep the air out.
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-
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-
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-
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-### 2. Chemical Solutions
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-If nitrogen is too expensive for your setup, you can use chemicals to inhibit oxidation:
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-* **Dross Reducers / "Anti-Dross" Powder:** These are antioxidant powders (like phosphorus-based pellets) added to the solder pot. They float on top and react with oxygen so the solder doesn't have to.
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-* **Solder Oils/Blankets:** A layer of specialized heat-stable oil is floated on the surface of the molten solder to create a physical barrier against air.
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-
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-### 3. Equipment & Process Optimization
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-Mechanical turbulence is a major "dross generator." Every time the solder splashes or ripples, more surface area is exposed to air.
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-* **Reduce Wave Height:** Keep the solder wave as low as possible while still making contact with the PCB.
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-* **Minimize Turbulence:** Ensure pump speeds are steady and that the "fall" of the solder back into the pot is smooth rather than splashing.
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-* **Standby Mode:** Use machines that automatically lower the pump speed or turn off the wave when no PCBs are detected on the conveyor.
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-* **Keep the Pot Full:** A low solder level increases the distance the metal "falls" back into the pot, creating more bubbles and turbulence.
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-
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+## 4. Solder Paste Storage & Maintenance
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+Oxidation often starts in the container, especially at high temperatures ($30^\circ\text{C}+$):
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+* **Flux Separation:** Solder powder settles, and oily flux rises to the top.
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+* **Premature Activation:** Heat exhausts the flux's cleaning power before use.
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+* **Powder Oxidation:** Heat catalyzes the formation of Tin Oxide on the tiny spheres.
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-### 4. Solder Quality & Maintenance
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-* **Use Low-Drossing Alloys:** Professional-grade solder bars (like SAC305 or Sn63Pb37) often contain trace amounts of **Germanium (Ge)** or **Phosphorus (P)** which act as "oxygen scavengers" to keep the surface shiny.
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-* **Controlled De-drossing:** When you must remove dross, use a **Solder Recovery System** (a mechanical press). "Raw" dross is actually 70%–90% good solder trapped in an oxide "web." These machines squeeze the good metal back out so you don't waste it.
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+### Storage Comparison
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+| Storage Temp | Expected Shelf Life | Quality Result |
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+| :--- | :--- | :--- |
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+| **$0\text{--}10^\circ\text{C}$ (Fridge)** | 6–12 Months | **Professional.** Shiny joints. |
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+| **$20\text{--}25^\circ\text{C}$ (Room)** | 1–2 Months | **DIY Grade.** May need extra flux. |
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+| **$30^\circ\text{C}+$ (Warm)** | < 3 Weeks | **Poor.** High risk of grey joints. |
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-### Comparison Summary
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-| Method | Effectiveness | Cost | Best For |
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-| :--- | :--- | :--- | :--- |
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-| **Nitrogen ($N_2$)** | Highest | High (Gas costs) | High-volume, High-reliability |
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-| **Antioxidant Pellets** | Medium | Low | Small-to-medium shops |
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-| **Wave Optimization** | Low-Medium | Free (Process) | All wave soldering |
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-| **Solder Recovery** | High (for savings) | Moderate (Tool) | Reducing waste costs |
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+### How to Identify "Dead" Paste
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+* **The Stir Test:** If it's "chunky" or like "wet sand" and won't stir into a smooth cream, it's dead.
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+* **The Slump Test:** If it spreads out at room temperature, it will cause bridging during reflow.
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+* **The Solder Ball Test:** Heat a dab on scrap PCB. If it forms one shiny ball, it's good. If it leaves tiny "satellites" (grey dust), it's heavily oxidized.
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-> **Pro Tip:** If you are seeing "grainy" or "dull" joints on your PCBs, it’s a sign that dross is being sucked into the pump and mixed into your solder joints. Always skim the surface regularly but gently—vigorous stirring actually creates more dross!
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+### Recovery Methods
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+* **Manual Homogenization:** Stir vigorously for 2–3 minutes until it looks like creamy peanut butter.
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+* **Rescue Flux:** Adding a few drops of **Tacky Flux** can sometimes revive dry paste, but it increases the risk of "runny" paste (lower viscosity).
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+---
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+## 5. Fixing "Grey" or Oxidized Joints
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+If joints are already dull (overheated or oxidized):
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+1. **Apply Tacky Flux:** Cover the joint with high-quality flux.
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+2. **Re-Reflow:** Briefly use a hot air station (~300°C) or a clean soldering iron tip. The flux will chemically reduce the oxides and allow the metal to flow into a shiny, silver shape.
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-## ref
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+## References
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+- [[solder-paste]]
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+- [[soldering-dat]]
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+
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fab-dat/fab-PCB-soldering-tools-dat/fab-PCB-soldering-tools-dat.md
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soldering iron rack - https://www.electrodragon.com/product/casting-metal-soldering-rack/ - [[PSOS010-dat]]
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-
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+- [[heat-isolator-dat]]
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- [[preheat-bed-dat]]
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fab-dat/fab-PCB-soldering-tools-dat/fab-soldering-materials-dat/fab-soldering-materials-dat.md
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-# soldering-materials-dat
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+# fab-soldering-materials-dat
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fab-dat/fab-PCB-soldering-tools-dat/fab-soldering-materials-dat/solder-paste-dat/2025-08-08-12-11-20.png
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fab-dat/fab-PCB-soldering-tools-dat/fab-soldering-materials-dat/solder-paste-dat/flux-thinner-dat/flux-thinner-dat.md
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+# flux-thinner-dat
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+
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+- [[PCB-soldering-dross-dat]] - [[fab-PCB-soldering-dat]]
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+
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+
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+
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+
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+## Solder Paste Thinner: Essential Guidelines
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+
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+The liquid used to adjust the viscosity of solder paste is professionally referred to as **Solder Paste Thinner** (or Flux Thinner).
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+
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+**CRITICAL WARNING:** In professional electronics manufacturing, **it is generally discouraged to thin solder paste.** Solder paste is a carefully engineered chemical mixture. If it has dried out or expired, the flux activity and the rheology (flow characteristics) have already been degraded. Adding a thinner often results in:
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+* **Bridge defects** during reflow.
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+* **Solder beading** or "tombstoning" due to altered wetting properties.
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+* **Voids** in the solder joint caused by improper solvent evaporation.
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+
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+---
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+
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+### 1. Composition
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+Specialized solder paste thinners typically consist of:
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+* **Glycol Ethers (e.g., Propylene Glycol Ethers):** These are the primary solvents that dissolve the resin/rosin binder.
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+* **Surfactants:** Added to maintain the thixotropic properties (the ability to flow under shear stress but stay stationary when idle).
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+* **Stability Agents:** Prevent the metal particles from settling out of the flux medium.
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+
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+### 2. Best Practices for Use
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+If you must attempt to salvage a paste (for non-critical prototyping), follow these strict rules:
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+
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+* **Use Only Professional Grade Thinner:** Do not use general solvents like acetone, lacquer thinner, or standard hardware store cleaners. These will chemically destroy the flux.
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+* **Minimal Dosage:** Add only **1% to 3% by weight**. Adding too much will cause the paste to slump, leading to shorts between fine-pitch pads.
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+* **Homogeneous Mixing:** Use a mechanical or manual spatula to stir the paste for at least 3-5 minutes until the consistency is uniform.
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+* **Stabilization:** Let the paste sit for at least 30 minutes after mixing before using it to allow the chemical solvents to distribute evenly.
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+
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+
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+
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+### 3. Troubleshooting "Dry" Paste
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+Before reaching for a thinner, check these common issues:
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+* **Temperature (The #1 Culprit):** Solder paste must be stored in a refrigerator (typically 2°C–10°C). It **must** be brought to room temperature (naturally, in its container) for at least 2–4 hours before opening. If opened while cold, moisture from the air will condense into the paste, causing it to appear dry or gritty.
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+* **Shelf Life:** Check the expiration date. Once the activator in the flux is exhausted, no amount of thinner will restore the paste's ability to create a reliable solder joint.
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+
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+### 4. Important Distinction
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+* **Thinners:** Are for modifying the paste's viscosity.
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+* **Cleaners (IPA/Alcohol):** Are for removing flux residues **after** soldering or cleaning stencils. **Never mix these into your solder paste.**
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+
fab-dat/fab-PCB-soldering-tools-dat/fab-soldering-materials-dat/solder-paste-dat/solder-paste-dat.md
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# solder-paste-dat
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+- [[soldering-paste-low-temperature]] - [[solder-paste-dat]] - [[fab-soldering-materials-dat]]
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+
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+- [[PCB-soldering-dross-dat]] - [[fab-PCB-soldering-dat]] - [[flux-thinner-dat]]
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+
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+
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- [[high-precise-printing-dat]]
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- [[fab-PCB-soldering-dat]] - [[solder-paste-dat]]
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+- [[fab-stencil-printer-dat]] -
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## supporting tools
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-## Solder Paste Thinner: Essential Guidelines
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-
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-The liquid used to adjust the viscosity of solder paste is professionally referred to as **Solder Paste Thinner** (or Flux Thinner).
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-
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-**CRITICAL WARNING:** In professional electronics manufacturing, **it is generally discouraged to thin solder paste.** Solder paste is a carefully engineered chemical mixture. If it has dried out or expired, the flux activity and the rheology (flow characteristics) have already been degraded. Adding a thinner often results in:
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-* **Bridge defects** during reflow.
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-* **Solder beading** or "tombstoning" due to altered wetting properties.
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-* **Voids** in the solder joint caused by improper solvent evaporation.
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-
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----
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-
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-### 1. Composition
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-Specialized solder paste thinners typically consist of:
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-* **Glycol Ethers (e.g., Propylene Glycol Ethers):** These are the primary solvents that dissolve the resin/rosin binder.
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-* **Surfactants:** Added to maintain the thixotropic properties (the ability to flow under shear stress but stay stationary when idle).
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-* **Stability Agents:** Prevent the metal particles from settling out of the flux medium.
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-
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-### 2. Best Practices for Use
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-If you must attempt to salvage a paste (for non-critical prototyping), follow these strict rules:
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-
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-* **Use Only Professional Grade Thinner:** Do not use general solvents like acetone, lacquer thinner, or standard hardware store cleaners. These will chemically destroy the flux.
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-* **Minimal Dosage:** Add only **1% to 3% by weight**. Adding too much will cause the paste to slump, leading to shorts between fine-pitch pads.
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-* **Homogeneous Mixing:** Use a mechanical or manual spatula to stir the paste for at least 3-5 minutes until the consistency is uniform.
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-* **Stabilization:** Let the paste sit for at least 30 minutes after mixing before using it to allow the chemical solvents to distribute evenly.
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-
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-
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-
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-### 3. Troubleshooting "Dry" Paste
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-Before reaching for a thinner, check these common issues:
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-* **Temperature (The #1 Culprit):** Solder paste must be stored in a refrigerator (typically 2°C–10°C). It **must** be brought to room temperature (naturally, in its container) for at least 2–4 hours before opening. If opened while cold, moisture from the air will condense into the paste, causing it to appear dry or gritty.
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-* **Shelf Life:** Check the expiration date. Once the activator in the flux is exhausted, no amount of thinner will restore the paste's ability to create a reliable solder joint.
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-
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-### 4. Important Distinction
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-* **Thinners:** Are for modifying the paste's viscosity.
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-* **Cleaners (IPA/Alcohol):** Are for removing flux residues **after** soldering or cleaning stencils. **Never mix these into your solder paste.**
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-
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-
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-
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-## solder dross issue
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-
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-
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-### How to Fix "Grey" or Oxidized Solder Joints
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-
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-Grey joints are usually caused by **overheating** (burning off the flux), **underheating** (cold joints), or **slow cooling**. Follow these steps to "refresh" the joints:
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-
64
----
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-
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-### 1. The "Flux-and-Reflow" Method (Best for SMD)
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-If the joint is just dull but the component is correctly aligned, **Flux** is your best friend.
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-* **Apply Tacky Flux:** Cover the grey joints with a generous amount of high-quality "no-clean" or RMA tacky flux (e.g., Amtech NC-559).
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-* **Re-apply Heat:** * **Hot Air Station:** Set to ~280°C - 300°C with low airflow. Heat the area until you see the solder turn liquid and "jump" into a shiny, spherical shape.
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- * **Soldering Iron:** Touch the joint briefly with a clean, tinned tip. The flux will smoke and chemically "eat" the grey oxide layer.
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-* **Why it works:** Flux is a reducing agent. It chemically removes the oxygen from the "grey" tin-oxide and allows the pure metal to flow together again.
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-
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-
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-### What happens inside the can at $30^\circ\text{C}$?
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-
76
-1. **Flux Separation (The "Oil" Effect):** Solder paste is a suspension of heavy metal spheres in a lighter chemical flux. At $30^\circ\text{C}$, the flux becomes less viscous. The heavy solder powder will settle to the bottom, and a yellowish, oily liquid (the flux) will rise to the top.
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-
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-2. **Chemical Activity Loss:** Flux is designed to "activate" (clean oxides) at high temperatures. However, at $30^\circ\text{C}$, a slow chemical reaction begins prematurely. The flux starts "working" on the solder powder while it's still in the can, exhausting its strength before it ever touches your PCB.
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-
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-3. **Powder Oxidation:** Even in a "sealed" plastic can, there is trapped air (oxygen) inside. Heat acts as a catalyst. The microscopic surface area of the solder spheres is massive, and $30^\circ\text{C}$ provides enough energy for a thin layer of **Tin Oxide** ($SnO$ or $SnO_2$) to form on every single sphere.
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-
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-
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-
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----
85
-
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-### How to tell if your paste is "dead"
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-Before using it on a real project, perform these three checks:
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-
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-* **The Stir Test:** Open the can. If there is a thick layer of liquid on top, try to stir it back in. If it remains "chunky," "dry," or like "wet sand" that won't smooth out, the flux has evaporated or polymerized. **Throw it away.**
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-* **The Slump Test:** Apply a small amount to a surface. If it spreads out and loses its shape (slumps) at room temperature, it will likely cause "solder bridges" (连锡) during reflow.
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-* **The Solder Ball Test:** Put a small dab on a piece of scrap PCB and heat it with a heat gun.
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- * **Good:** The paste melts into one single, shiny, beautiful silver ball.
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- * **Bad:** The paste melts but leaves behind dozens of tiny "satellites" (small grey dust-like balls) around the main drop. This is a sign of heavy oxidation.
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-
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----
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-
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-### Comparison of Storage Conditions
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-| Storage Temp | Expected Shelf Life | Resulting Quality |
99
-| :--- | :--- | :--- |
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-| **$0\text{--}10^\circ\text{C}$ (Fridge)** | 6–12 Months | **Professional Grade.** Shiny joints, minimal dross. |
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-| **$20\text{--}25^\circ\text{C}$ (Room)** | 1–2 Months | **Acceptable for DIY.** May require extra flux. |
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-| **$30^\circ\text{C}+$ (Warm)** | < 3 Weeks | **Poor.** High risk of grey joints and solder beads. |
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-
104
----
105
-
106
-### Can you fix it?
107
-If you *must* use this paste and it has separated:
108
-1. **Manual Homogenization:** Stir it vigorously for at least 2–3 minutes with a clean spatula until it looks like creamy peanut butter.
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-2. **Add "Fresh" Flux:** If the paste feels dry, add a few drops of high-quality **Tacky Flux** (like NC-559) and mix it in. This can sometimes "rescue" oxidized powder by providing the extra cleaning power needed to break through the $30^\circ\text{C}$ oxide layer.
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-
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-
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-## “Solder paste should be more viscous so it doesn’t spread or drip.”
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-
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-- **More viscous** → thicker, stickier, flows slowly
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- → Good for solder paste — it stays where you apply it.
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-
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-- **Diluted** → thinned by adding liquid (like flux or solvent)
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- → Not good — it becomes too runny and won’t hold components well.
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-
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-
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-
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-
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-
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-## Low temperature soldering paste
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-
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-Low temperature soldering paste is a type of solder paste designed to melt and flow at lower temperatures than standard solder pastes. Here are its main features:
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-
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-- Melting Point: Typically melts between 130°C and 180°C, compared to standard lead-free solder pastes which melt around 217°C.
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-- Composition: Often contains bismuth-based alloys (e.g., Sn42/Bi58) instead of traditional tin-silver-copper (SAC) alloys.
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-- Applications: Ideal for temperature-sensitive components, rework, or double-sided PCB assembly where high heat could dam-Age parts.
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-- Reduced Thermal Stress: Minimizes risk of warping or dam-Aging PCBs and components.
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-- Energy Saving: Lower reflow oven temperatures reduce energy consumption.
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-- Compatibility: Useful for mixed-technology boards or assemblies with plastic connectors and LEDs.
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-
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-
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-
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138 26
### Solder Paste Types and Applications
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@@ -151,12 +39,6 @@ Low temperature soldering paste is a type of solder paste designed to melt and f
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-## target
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-
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-- [[FPC-dat]]
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-
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-
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-
160 42
## Common type Solder Paste
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162 44
| melting point | tin content | Note |
... ...
@@ -169,6 +51,10 @@ Low temperature soldering paste is a type of solder paste designed to melt and f
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+
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+
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+
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+
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![](2024-02-17-16-19-00.png)
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![](2024-02-17-16-20-20.png)
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@@ -177,9 +63,10 @@ Low temperature soldering paste is a type of solder paste designed to melt and f
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![](2024-02-17-16-20-49.png)
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-## solder paste printer
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-![](2025-08-08-12-11-20.png)
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+## target
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+
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+- [[FPC-dat]]
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... ...
@@ -187,4 +74,4 @@ Low temperature soldering paste is a type of solder paste designed to melt and f
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188 75
- [[solder-paste]]
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-- [[soldering-dat]]
... ...
\ No newline at end of file
0
+- [[fab-PCB-soldering-dat]]
... ...
\ No newline at end of file
fab-dat/fab-PCB-soldering-tools-dat/fab-soldering-materials-dat/solder-paste-dat/soldering-paste-low-temperature/soldering-paste-low-temperature.md
... ...
@@ -0,0 +1,18 @@
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+
2
+
3
+# soldering-paste-low-temperature
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+
5
+
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+
7
+
8
+## Low temperature soldering paste
9
+
10
+Low temperature soldering paste is a type of solder paste designed to melt and flow at lower temperatures than standard solder pastes. Here are its main features:
11
+
12
+- Melting Point: Typically melts between 130°C and 180°C, compared to standard lead-free solder pastes which melt around 217°C.
13
+- Composition: Often contains bismuth-based alloys (e.g., Sn42/Bi58) instead of traditional tin-silver-copper (SAC) alloys.
14
+- Applications: Ideal for temperature-sensitive components, rework, or double-sided PCB assembly where high heat could dam-Age parts.
15
+- Reduced Thermal Stress: Minimizes risk of warping or dam-Aging PCBs and components.
16
+- Energy Saving: Lower reflow oven temperatures reduce energy consumption.
17
+- Compatibility: Useful for mixed-technology boards or assemblies with plastic connectors and LEDs.
18
+
fab-dat/fab-PCB-soldering-tools-dat/heat-isolator-dat/2026-06-08-00-01-22.png
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fab-dat/fab-PCB-soldering-tools-dat/heat-isolator-dat/2026-06-08-00-06-49.png
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fab-dat/fab-PCB-soldering-tools-dat/heat-isolator-dat/heat-isolator-dat.md
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@@ -0,0 +1,12 @@
1
+
2
+# heat-isolator-dat
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+
4
+
5
+20m 铝箔胶带 == 耐高温/隔热/耐老化/防水/补漏
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+
7
+![](2026-06-08-00-01-22.png)
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+
9
+![](2026-06-08-00-06-49.png)
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+
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+
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+## ref
... ...
\ No newline at end of file
fab-dat/fab-Stencil-printer-DAT/2025-08-08-12-11-20.png
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fab-dat/fab-Stencil-printer-DAT/fab-Stencil-printer-DAT.md
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@@ -3,6 +3,8 @@
3 3
4 4
- [[fab-stencil-dat]] - [[fab-stencil-printer-dat]] - [[fab-stencil-frameless-dat]] - [[fab-stencil-frame-dat]]
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+- [[solder-paste-dat]]
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+
6 8
7 9
- [[fab-PCBA-dat]]
8 10
... ...
@@ -12,6 +14,9 @@
12 14
- [[fab-stencil]]
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14 16
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+## solder paste printer
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+
19
+![](2025-08-08-12-11-20.png)
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17 22
## Features