I drove to a local electronics shop this morning

I found some aluminum foil tape that was "50 mm"

but they only had kapton tape up to "50 mm" ...

Searching on ebay I was finding 60 mm kapton tape that would cover the aluminum tape perfectly, but that would be a couple weeks away.

Trying to decide If I can get the 60 mm tape in time ... or if overlapping kapton tape would be okay for this?
(would the overlap have to be consistent the whole length?)

the 555 timer they had was a regular one not the 2Mhz 555 timer that was suggested it might be needed for low capacitance's involved in this

I guess googling tone generator circuit might help me on that side