This is an easy detector to make, works well, and just about any young teen should be able to fashion one in just a little while, with no soldering. The only tools used were a pair of needle nose pliers a screwdriver, and a pipe cutter or hack saw to cut the copper tube. Parts are minimal. The one in the photo below is a replica of the first detector I made when starting in the hobby.
Once you've gathered all the parts you can bend the wire. Leave a little extra on the end until you're done bending the wire, it's easier to bend. When you're done bending the wire cut the excess off the end with the needle nose. Wrap four or five turns of the sixteen guage around the copper pipe and then use the needle nose to squash the turns together. Make sure it's not too tight, the pipe should slide easily through the wire 'tunnel'. When that's done, grab the wire about two inches away and twist a loop in the wire. Cut the end and then bend the loop horizontal. When you're done it should look something like the picture below. Cut a length of wire and fashion your alligator clip wire like in the picture.
Next, slide the catwhisker into the copper tube until the end just sticks out of the other end of the copper tube. Secure it in place by crimping the end of the copper tube on it. The crimp will hold the catwhisker in place and wooden bead as well.
You can now assemble all the parts and your finished product should look something like the top photo. This detector should be used on a solid surface, it is sensitive to table and floor vibrations, but is otherwise easy to use and works surprisingly well for the amount of time, money, and effort it takes to make one. The wood base should be fairly heavy so the detector holds still while you're looking for the hot spot on your galena.
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