Ground plane until the limit of the board?

[Winsu]

Hi All,

What pros and cons can we find allowing the ground plane going to the limit on the board?.

Is it a good practice or it is actually taking some risk?.

Cheers

 

[betwixt]

pro: if the board is being etched it means less copper is removed an therefore the etchant lasts longer.
con: greater risk of electrical contact with anything touching the board edge.

Real answer: it depends entirely on the purpose of the board and its design. There is no right or wrong.

Brian.

 

[senilicus]

Never have a plane going to the board edge, Always keep a distance from the board edge, UNLESS IT IS ABSOLUTELY NECESSARY.

When routing the board from the Manufacturing Panel, a plane on the board edge can cause shorts.

 

[Winsu]

In my case I apply silicon to the edges of the baord, so probably it will prevent possible short with something...

 

[FvM]

I guess silicone rubber rather than silicon?

 

[andre_luis]

Never have a plane going to the board edge, Always keep a distance from the board edge.

In fact, this is a practice applied so often that there are CADs which when we create a PCB template from their Wizard tools, by default it is added a keepout contour layer internally to the board edge layer.

 

[Winsu]

FvM we apply silicon to fit a piece of plastic that cover the PCB. It is single layer so the risk of contact is less. Thanks to everyone for the input.