Big Tess (Classic Tesla Coil)

Big Tess

The Primary coil is wound from 5mm copper tubing  held by an acrylic framework, A modified fuse holder allows the tap to be varied.
The Secondary is wound with 0.4mm diameter enamelled wire onto a 24" long 110mm(4") former made of PVC soil pipe. 1130 Turns. 

The Topload is 2 x 8" diameter mixing bowls.

The Spark gap is a linear RQ design, 10 indervidual gaps to around 0.5mm  made from copper 12.5mn water pipe and 2 x 80mm fans to give an air flow around them for spark quenching.
The Capacitor is now an MMC made of 72 x 0.047uF Capacitors each rated at 1.5Kv giving a total capacitance of 24nf

So I had a 10Kv 40Ma NST lying about.. I decided to build a bigger coil. 
First run 15" sparks, which is pretty poor for the size of coil. The Origonal MMC (10x25Kv 2.2nF Polyestercaps ) made a very loud banging noise. I suspect they don't like the current. A New MMC has now been built. 

M y origonal sparkgap was an RQ gap with 5 gaps at 1mm. This didn't seem to give a very good quench, so the new Gap was constructed.  

New Gap runs well, and I got given another 50ma NST so now running at around 1 KW with 2 NST's

New Config worked so well Ihad to change the top load to a 8" sphere, but safety gap kept firing, Time to build a filter.

Toploads

 2 x 8" frisbee's covered in aluminium tape

or

2 x 8" stainless steel mixing bowls from Ikea.

The Spark gap is a linear RQ design, 10 individual gaps to around 0.5mm  made from copper 12.5mn water pipe and 2 80mm fans to give an air flow around them for spark quenching.
The Capacitor is now an MMC made of 72 x 0.047uF Capacitors each rated at 1.5Kv giving a total capacitance of 24nf

RF Filter

2 x 100t coils on 3/4" pvc water pipe, 4 x ferrite interference suppressors epoxied in side the tubes 2 in each. 4X 470 Ohm 10W resistors in series, with 4 x 100pf giving 50pf across each winding of the NST's

Controller with keyswitch, "If the keys in my pocket its safe to approch the coil!!",
The other two switches give me a 2 stage power input by separatly switching in the NST's
Picture taken outside in a moderate breeze, shows nice banjo effect as ark is blown around, sparks are about 2.5' long.

Streamers 2.5' long

New Topload.

Well they don't have to be circular.
Theory is that all the charge collects at the pointy end.

Topload appears to work. 2.5' arcs in windy conditions outside.
I had to stop when I had a connection problem and my Primary tracked across the acrylic to earth.