Help with surf pi kit please

[bigted]

Howdy all

Sorry but I am new to this. I am building a surf pi kit and i have few questions.

What sort of speaker should i use eg watt and ohm rating?

Can i use metal screws when attaching the coil and cover to the shaft?

When I put the coil in the cover should i put it on the top or bottom of the cover?

Any help would be greatly appreciated.
Regards
bigted

[jatmar]

I built the surf pi 1.2 also from a kit and would not recommend using any metal screws near the coil. You can use a pvc pipe for a shaft and hardware stores sell vinyl screws, or at least that is what I used. I would also recommend binding the coil windings tightly to prevent them from moving while you detect and bump into things which would cause false signaling. I encapsulated my coil in epoxy. It's a nice kit. Take your time. Make a few different coils and see which one works best for you. I used a 9 inch round coil using 23 turns of .5mm stranded copper wire stripped out of telephone cable. After tuning I'm getting a little over 10 inches on a U.S. Nickel and average sized gold wedding band. Not too bad for a weekend DIY Project. Hope this helped you out and happy hunting...Jatmar

[bigted]

Cheers for that mate

[bernte_one]

u can also try a nonmagnetic stainless steel screw
i think of all metal screws the will have the lowest influence on the magnetic field

[bigted]

Thanks. The wire you used, does it still have the plastic coating left on. Also how did you wind the coil. Cheers mate.