Hall effect type sensor through 100mm of Wood

[roofz]

Hi All

Im trying to find a sensor of some sort which would switch on when it detects magnet through around 100-150mm of Wood. Either a hall effect sensor or something of the like? The reason id want to use it switch form is for low power usage as itd be powered by a battery.

 

[Arouse1973]

Google hall effect switches, reed switches, and neodymium magnets. You could easily get 6 inches with the right sensor and large enough magnet.
Adam

 

[duke37]

Wood will have no effect on the magnetic field unless it is wet and the field is changing (eddy currents)