How to improve the strength of PCB board?

[solofrain]

I need to install a 20inx12in PCB board on a vehicle. How can I improve the strength of the board so that it won't bend?

 

[thylacine1975]

Make it thicker!

For illustration purposes I found two (blank) PCBs of differing thicknesses - one is (tinned) double sided 1.6mm thick and the other a 4 layer board (from an old project) that is 4.0mm thick. Both boards are approximately 300mm wide. Clamping both in the vice, I pulled...
(and what you can't see is that I'm pulling *much* harder on the 4.0mm board!)

And a picture tells a 1000 words...

(I'm sure beam deflection formulae (https://en.wikipedia.org/wiki/Deflection_(engineering)) would yield a far superior scientific approach to deciding how thick a PCB you need, but you get the idea

 

[FvM]

Essentially, the bending stiffness is proportional to board thickness raised to the square. And it's slightly increased by continuous power planes and copper pours.

For the said board size, a metallic frame might be appropriate.

Vibrations must be expected on a vehicle. At worst case hitting the self resonance frequency of your board...

 

[spudboy488]

Google "board stiffener". There are various ways to do this.

 

[solofrain]

Make it thicker!

For illustration purposes I found two (blank) PCBs of differing thicknesses - one is (tinned) double sided 1.6mm thick and the other a 4 layer board (from an old project) that is 4.0mm thick. Both boards are approximately 300mm wide. Clamping both in the vice, I pulled...
(and what you can't see is that I'm pulling *much* harder on the 4.0mm board!)

And a picture tells a 1000 words...

(I'm sure beam deflection formulae (https://en.wikipedia.org/wiki/Deflection_(engineering)) would yield a far superior scientific approach to deciding how thick a PCB you need, but you get the idea

Thank you thylacine1975 for the input. 4mm looks really strong:lol: My board is now 3mm thick and I can't increase it because of some through hole connectors...

 

[solofrain]

Essentially, the bending stiffness is proportional to board thickness raised to the square. And it's slightly increased by continuous power planes and copper pours.

For the said board size, a metallic frame might be appropriate.

Vibrations must be expected on a vehicle. At worst case hitting the self resonance frequency of your board...

Thank you FvM. My board has several pwr/gnd planes. Hope they will help. Resonance frequency... Is there any way to change it, if it happen to be the worst case?

- - - Updated - - -

Google "board stiffener". There are various ways to do this.

This should help. Thanks. It reminds me of the stiffener I used on my speakers.:lol: