Finishing the toroid mount

Spent a little time tonight soldering a small piece of copper tube onto the end of the winding wire at the top of the secondary coil. Although my final design for mounting the toroid means I will not have to keep disconnecting this wire, it's still good practice and makes a very secure attachment. I didn't take any close up pics of the wire at the top of the secondary but heres a pic of the bottom connection showing the little piece of strengthening copper tube soldered onto the end of the magnet wire. Don't forget to remove the varnish from the wire before you solder.

Completion of this job meant I could do a final assembly on the toroid mount. I had already removed the top cap from the secondary so I could insert the brass bush made to convert the hole from 10mm to 8mm. Next a copper lug was placed onto the copper mounting pin and the pin inserted up through the brass bush. One of the perspex spacing disc was placed over the pin and then a stainless washer and finally the M8 stainless nut. As the pin was now captive the top cap could be secured in place, remembering to make the electrical connection by placing the soldered tube into the copper lug.

After securing the top cap back onto the secondary with the 8 nylon bolts the next spacer was fitted to the top cap.

This perspex spacer is the one with a 25mm circular cut-out in the centre and allows the securing bolt to be counter sunk into the assembly so the toroid rests on the large face of the perspex disc rather than the top of the nut. I was going to bond this disc to the one underneath but on second thoughts I dont think it needs to be, plus, if I leave it separate, it will be easier to modify.

With that done I remounted the secondary coil assembly back onto the base assembly and placed the toroid over the mounting pin and secured in place with the M8 knob.

Here's a shot from underneath. Should be reasonably simple to adjust the height of the toroid by adding or removing perspex spacers.

The toroid can be easily removed and fitted by a quick spin of the knob with no additional need to make and break an electrical connection. Pretty neat and totally over engineered as usual.


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