Soldering

Authors:

Geoffrey Hunter

Published On:

Aug 27, 2013

Last Updated:

Mar 14, 2021

SMD components during a reflow soldering process.

Manually Applying Solder Paste

Plastic syringe tips are usually better than metal ones, as they offer less friction to the paste, making it easier to control the amount of paste which comes out.

Solder Paste Dispensing Machines

If you are applying solder paste by hand (as opposed to using a template), you can purchase machines which help automatically dispense a measured amount of solder paste from the syringe. Most are operated with air pressure and require an external air compressor (recommended to be at least 1.5HP). You can also get based around linear motors and peristaltic pumps. Common models from AliExpress include:

YDL-983A
AD-982

Model Number	Features	Vendor	Vendor Price
xxx-982	Analogue dials	AliExpress	US$70 (inc. shipping)
xxx-983A	Digital dials	AliExpress	US$120 (inc. shipping)

Pre/Post Soldering Heaters

Many components require controlled pre-heating and post-cooling to solder effectively.

Soldering Defects

Tombstoning

TODO: Add info.

Head-In-Pillow (HiP)

AIM Solder has a great paper on head-in-pillow defects at https://aimsolder.com/sites/default/files/head-in-pillow_bga_defects.pdf (cached local copy).