Doubt about control box material

[cristiano.sar]

I'm in doubt of using aluminum sheet metal to build my own metal detectors control box (in a shape like the SD/GPX) or plastic like ABS (vacuum formed or 3d printed). I know aluminum or other metals provide a native good EMI protection. What are the alternatives other than using copper/al tape for EMI protection when using plastic boxes?
I have seen a video of x-terra being repaired and I have not noticed any kind of shield in the control box, is it really needed?
Thanks.

[Carl-NC]

Some circuits need shielding, some do not. With plastic, you can also use a spray conductive paint on the inside.

[kt315]

I know aluminum or other metals provide a native good EMI protection

in metaldetecting is NO EMI protection. not exists. you protect just from ESFI. think - EMI easely goes in your coil.

[Carl-NC]

EMI easely goes in your coil.

The coil is already shielded against electric field EMI so, yes, it can still pick up magnetic field EMI. Without shielding, the circuit can pick up electric field EMI, which is why you would add shielding. You could also shield the circuit from magnetic field EMI, but usually that's not as big a problem. Whether a circuit is susceptible to EMI depends a lot on the circuit, and can even depend on the layout.

[kt315]

i had folders in the forum with digests of pics, shielding was among them. i showed all types of shielding in different manufacture metal detectors like the examples how-to-right-do.
however all were deleted. possibly after refreshing of forum engine on new revising, i can not know.

[cristiano.sar]

Thank you all.
kt315, I think your shielding pictures are here in your profile media: https://www.geotech1.com/forums/member/74-kt315/media, under "right shielding".

[kt315]

ops... thank you. i did not guess that now the folders are in 'media'