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Old 07-21-2015, 12:06 PM   #7 (permalink)
DIGItonium
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That can happen if you don't have the right tools. Thinner solder is a good start. The smallest tip is very sharp. The solder reworking station I have from Metcal is pretty pricey. The cheapest is around the $300 range. The one I have is discontinued, but it was my first from over 10 years ago. It heats the solder around 600F. It's really nice, and I can rework very small surface mount parts including flash memory (fine pitch).

Below is a list of some of the tips available for my particular tool:
SSC Series Conical new

Here's a generic example of a sharp tip:
http://www.amazon.com/Metcal-SFV-CNB.../dp/B007QT1K84

For surface mount LEDs, capacitors, resistors, etc., it's possible to remove and replace components without using a heat gun:
  1. Clean and tin the tip with solder.
  2. Heat the contact ends of the component and PCB pads with additional solder (hold it around a 45 degree angle, and rest your hand to help leverage the tip). You basically want to add blobs and work both ends quickly so you can slide off the component. Goal is to get this done in a few seconds so you don't overheat and rip the pads.
  3. Use solder wick to remove excess solder on the surface and PCB pads, and go back with Isopropyl Alcohol using Kimwipe or cotton swab.
  4. Clean and tin the tip, heat up one PCB pad, and dab some solder on the pad. It doesn't take much.
  5. Use tweezers to align and hold the part on the pad, and heat the component contact and PCB pad. This should allow solder to flow and make contact with both surface. That is enough to mechanically hold the component so you can solder the remaining contacts. If necessary, go back and resolder the first contact. The goal is to get this done in a few seconds so you don't end up damaging the component and PCB pads.
  6. For cleaner work, use a flux pen to dab the contacts with some flux. Then heat the tip of the contact and PCB pad. It will sizzle a bit, and you'll be left with clean solder work and reduce the likelihood of cold solder joints.

For practice, get a dead motherboard or PCB with surface mount parts. Practice removing and replacing parts on it.
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Last edited by DIGItonium; 07-21-2015 at 12:08 PM.
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