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construction of my 12 x 36 open frame acrylic secondary

Jim Fosse : per your request

material list for 12" x 36" secondary
2 pcs 0.25" acrylic sheet 13" diameter
3 pcs 0.125" acrylic sheet 13" diameter
12 0.5" acrylic rods 36.5" long
Scribe 11.5" diameter circles on each sheet. Using these circles as
centers, bore 12 0.5" holes spaced 30 degrees apart. The 2 0.25" sheets
are the end plates. Glue the acrylic rods between the end plates so
that the rods are flush to the outside end of the plates. the rods 
form the surface on which the wire will be wound. Cut the 0.125" sheets
on the 11.5" diameter cicle after the 0.5" holes have been bored. you
now have  circular pieces with 12 bites taken out of the edges. These
pieces are placed inside the rod structure and spaced evenly to support 
the rods which you will find are quite weak. After the supports are
glued in, the whole structure, although light, is quite sturdy. I use
#16 guage wire for my secondaries and it is wound directly on the rods.
I have not used any coating on the wire yet. Last night I exceeded 48"
discharges using a 15kv 120 ma neon driven at 85 v from the line.
Couldn't go any higher because the 15A breaker kept going out.
I expected to have harmonic problems because the winding is not 
perfectly round but I can't find any problems using a scope and sig
generator and the waveform in the discharges is classical Tesla with a
very long ring time which I attribute to the very high Q. I think the 
solid 0.125 supports will also help to prevent discharges through the 
center of the structure. I didn't mention that the discharges referred to 
above are on a just completed unit which is 14" in diameter and 30" high.
The 12" x 36" unit peaks out near 48" using a 12kv 120 ma neon. I have 
not experienced any turn to turn arc over. The wire I use is standard 
600v machine tool wire.

Hope this is clear. If not let me know  

Skip Greiner