Everything you wanted to know about soldering and desoldering but were afraid to ask

[E-design]

A very good demonstration of expert soldering and desoldering techniques.
https://www.youtube.com/watch?v=M0wI-5YZQm4

 

[albert22]

Thanks. Very good indeed although the guy makes it very easy, it requires a lot of practice. It is worth to see the full 1:17hs.
I would like to see a solution where the leads are not accessible from the top like large radial leads capacitors on large ground multilayer boards. They usually have small clearance and lots of dissipation so extracting the solder is very difficult and usually the pad or the thruhole gets ruined.

 

[E-design]

Here is another series by PACE on rework and repair of electronic pcb's.
Lesson 1
Lesson 2
Lesson 3
Lesson 4
Lesson 5
Lesson 6
Lesson 7
Lesson 8

Basic Soldering Series (A must for beginners)
Lesson 1: Solder & Flux
Lesson 2: Soldering to PCB Terminals
Lesson 3: Cup Terminals
Lesson 4: Bifurcated Terminals
Lesson 5: Hook and Pierced Terminals
Lesson 6: Component Soldering
Lesson 7: Soldering DIP Packages
Lesson 8: Integrated Circuits
Lesson 9: Flatpack & Other Planer-Mounted

 

[geekpcbguy]

Can you guys suggest solder paste brands? I've been looking at different websites to buy some, but I'm not sure if I should go for a good expensive one or just a cheap regular one. From what I understand Kester is top of the line.. Can you give me some suggestions?

 

[Rattanee]

T
I would like to see a solution where the leads are not accessible from the top like large radial leads capacitors on large ground multilayer boards.

I know this isn't a very recent post, but practice provides the best solutions so I thought I'd share.

In such a situation, my solution is to use a hot-air station in tandem with my desoldering station. Before you do anything, use a soldering iron to add a decent sized solder-blob atop the existing joint. It just needs to adhere to the solder, you don't need to overheat the joint (to make sure you don't damage the through plating). This is just to make it easier for the desoldering iron to heat the joint.

Use a medium noozle on the hot air station, temperature around 300°c. Heat around the joints gently, moving the nozzle around constantly to make sure you don't burn the board.

Hold the hot air gun in one hand, the desoldering iron in the other. When the board has reached the appropriate temperature, simply apply your desoldering iron, and work as regular.

Enjoy your clean, undamaged through holes.

Protip: Due to some manufacturers liking to bend even cap legs in multilayer boards, it's best to use a desoldering nozzle that is just a little larger then the component leg. With practice, you can use this method to straighten the component leg with the desoldering iron before sucking out the solder.

Protip2: It takes time and practice to master 'when the board is hot enough' to pull the solder out and still not rip up any pads. There is also bound to be variations in air flow quantity and actual heat output of hot air stations, hence it's best to just practice on whatever junk that's beyond repair anyways. Grab a few junker motherboards from your local PC repair place and practice removing caps. After a few boards you'll be able to do this with ease.