Through-holes

Description:
Solder filled through-hole. There is too much solder at the walls of the through-hole. The successive placing of components could be considerably impaired. For a through-hole as such there is not enough solder. Partially acceptable defect.

Causes/Remedy:

• deficiencies in the soldering process (soldering angle, temperature)
• deficiencies in hot tinning for THD

Description:
same context as described above - general view

Causes/Remedy:

• deficiencies in the soldering process (soldering angle, temperature)

Description:
Thin metallization missing in a multilayer THD. Not acceptable

Causes/Remedy:

• deficiencies in the galvanizing process (copper)

Description:
Formation of burrs in the wake of drilling the boards. These residues of drilling which have not been removed (particles of base material, burr) were plated with copper in the successive electro-plating process and therefore block the passage. Not acceptable.

Causes/Remedy:

• insufficient cleaning after drilling
• drilling process not optimal

Description:
Same context as above, but to lesser extent.

Causes/Remedy:

• insufficient cleaning after drilling
• drilling process not optimal

Description:
Missing copper coating in a THD. Result: There is no surface to be wetted with solder. Not acceptable.

Causes/Remedy:

• deficiencies in galvanizing process (copper)

Description:
Because of missing copper coating this THD solder joint could not be done properly. Not acceptable.

Causes/Remedy:

• deficiencies in galvanizing process (copper)
• hole reveals very uneven walls (unsatisfactory)

Description:
Due to partly missing copper coating in the through hole the solder could not fully wet required area. Not acceptable.

Causes/Remedy:

• deficiencies in galvanizing process (copper)
• hole reveals very uneven walls (unsatisfactory)