Protel 99se all Solder Pad and through hole fill tear drops, many of them are failed, does it affect the board? What is the role of tear filling?

Tear Drops are caused by excessive drip connections between the pad and wire or between the wire and the guide hole. The purpose of setting the tear drops is to avoid the impact of a huge external force on the circuit board, avoid breaking the contact point between the wire and the pad or the wire and the guide hole. In addition, setting tear drops can make the PCB Board look more beautiful.
Teardrop is used to avoid reflection caused by sudden decrease of signal line width. It can make the connection between the wire and component pad to be smoothly transitioned, solving the problem that the connection between the pad and the wire is prone to fracture.
1. welding can protect the pad and avoid multiple welding failures.
2. Enhance the reliability of the connection (production can avoid uneven etching and cracks in the off-hole positions)
3. Smooth impedance to reduce sharp impedance changes

In the circuit board design, in order to make the pad more sturdy, to prevent the mechanical board when the pad and the wire are disconnected, often between the pad and the wire with copper film layout a transition zone, the shape is like a tear, therefore, it is often called "tear filling ).
You can execute the main menu command tools/teardrops... , The teardrop ptions (tears) Setting Dialog Box shown in 1 is displayed.
Figure 1 "Tear setting" dialog box
Next, we will introduce the role of each option area in the Settings dialog box.
① General option region settings
The settings in the general option area are as follows:
● All pads option: Used to set whether to perform the tear filling operation on all pad.
● All vias option: This option is used to set whether to perform the tear filling operation on all passing holes.
● Selected objects only option: This option is used to set whether to perform tear filling only on selected components.
● Force teardrops option: Used to set whether to force tear filling.
● "Create report" option: This option is used to set whether to generate a report file after the operation is completed.
② Action option region settings
The settings for each base in the action option area are as follows:
● Add single option: it indicates the add operation with tears.
● Remove single option: indicates a delete operation with tears.
③ Teardrop style option area settings
The settings in the teardrop style option area are described as follows:
● Arc single option: Indicates selecting arc to fill the tears.
● Track single option: indicates the use of wire form for tear filling.