The first thing I noticed about Tesla coiling is that you are constantly tweeking, modifying, and rebuilding the thing. Sooo,
my first big coil remained in the plywood case stage for a couple of years. While the coil was in its plywood case stage, I was procuring all sorts of neat useable items, such as cases, wire, crimp on connectors for welding cable, volt meters , amp meters, switches, insulators, etc.

        Eventually I had more than enough items to begin the revamp of the coil. The first step was to increase the power or voltage. I decided to go with a higher voltage. This entailed the modification of my existing pig to consist of putting 2 14,400V pigs in series for a grand total of 30,000 Volts of primary power!! Although the cut down pig case would have held both transformers, the insulators that extended into the case prevented me from doing so. So, I had to resort to the uncut pig case to proceed with my plans.

        Since I was using a controller that consisted of 2 1256D's run in parallel, I had to my option of supplying the piggie with 57 or so amps of power. The previous case was rather small and left no room for gauges to be mounted in it, so I made an upper section to hold the variac and gauges at an angle which is a bit easier on the ergonomics. Wood...  oak to be exact was my choice to make the upper section from. The oak upper section went together rather easily but, the lifting and mounting of the twin variac system was a bit tedious. These things when bolted together must weigh at least 150 lbs. Betwen drilling holes for gauges, mounting paralleling chokes and fuses and switches, the case became somewhat confining in short order.  I also tried to put together a phase adjustor for the Sync rotory gap and mount that on the front plate of the control box. Good thing I mounted rollers on the case, cuz it put on weight rather quickly.

        The next step was to put the pig and inductor into a case for safety and mobility reasons. This is another combo that got heavy fast. The pig by itself must weigh in at about 300 lbs oiled up. The inductor weighs 167 lbs, the case tips the scales at 80 lbs. Sooo..  we ended up with another mobile case which weighs about 550 lbs.

        The coil case, which consists of the cover from an old 30KVA transformer fit the bill. After removing the transformer, I placed the SRSG and caps into it. The base of the primary mount is made from oak flooring scraps and polyethelene pieces from plastic conveyor belting. I got ahold of some type of polyethelene stock and turned down 2 insulators for the hi voltage wires to connect to. All of the connections inside the case were made using # 4 stranded wire with welding cable connectors.
 

The BIGPIG coil  standing 9.5' from top to ground, the primary consists of 17 turns of 3/8" Cu. soft tubing at .25" spacing. Even with .25" spacing, at 30KV input there is still occasional arcing between turns. The secondary is cardboard tubing 12.5" in dia. well coated inside with several coats of P.U. varnish and the exterior is coated 2 times with Behr 50 . The windings consist of the bottom 10" being #10 THHN solid Cu., The remaining winds are #18 magnet wire for a continued length of 45 more inches. Thus a total wind length of 55". The grey item holding up the toroid is a 5 gallon bucket ( gives you an idea how big this thing really is). The Toriod is 14.5" chord dia. X 45" max dia. flex Al. duct hose.
 
 
 

The Controller cabinet has 2  1256D variacs in parallel for approximately 57Amps of current @ 300 V out. It is fed by 240 volts with a 75A breaker. The volt meters are rated for 150 V ( which I wired to approximate the voltage across each leg of the supply ) and the Amp meter is a 150A unit with a current transformer controlling it. The switch is a 3 pole "reversing" switch for a 25 hp DC motor. It is rated for ( I think) 60A capacity. The lower variac is used for phase control of the SRSG ( which I still have to get working).
 
 
 

The back side of the controller cabinet. Lots of goodies in here :)   lots of fuses in here to protect the variacs and 120V system from any expected problems. The supply voltage is applied to the case via the large yellow plugs on the back, the wire is a # 4 SO multi strand 4 conductor.
 
 
 

The upper end of the pig cabinet, I used Lexan 1/4" sheeting for insulative purposes. 30KV is alot more difficult to insulate when going thru bulkheads and panels.
I had to switch to solid Cu. wire from the insulators off of the pig to the bulkhead due to the previous wires jumping around and wanting to arc to each other when it was running. The wires attached to the bulhead insulators are rated for 40KV and are a # 6 core stranded ( what a find !!!  great stuff )
 
 

The lower end of the piggie cabinet. The inductor is rated for about 100 Amps at 300V but it is set for 60Amps untill I get a better feed to the shop. By adding wood shims between the "I" and the "E" of the core, I can increase the amperage to the piggie. The core cross section of the inductor is a whopping 25.5 square inches. No problems with saturation here :) It is wound with 3 sets of #10 solid THHN Cu. for 200 turns.
 
 
 
 

The case for the coil system. pretty much straight forward here, the case is the protective housing from an old 30KVA 480/240 transformer. Mounted inside of the case are the SRSG, the safety gaps, and caps.
 

The safety gap setup. The smaller 1/2" balls didnt hold off the potentials of 30KV, so I machined down some 1" brass stock round and created these instead. Gap spacing is about 3/4" from the center ball which is attached to the RF ground system. The insulators are attached to 1/4" Lexan sheeting for added insulative properties ( plus it is kinda neat looking when the coil is running when all the cover plates are on the case )
 

The primary coil assembly. The first 7 turns are at 45 degrees and the remaing turns are flat for a total of 17 turns. I find this design to be rather good, it allows increased coupling and a flat outer primary for ease of adjustments, and somewhat of a low profile for reduced strikes to the primary. ( altho I still plan to install a strike ring)
 

Since I am using 30KV I needed a bit more insulative properties when passing cables thru the primary base. I drilled a hole in the base and placed this ceramic insulator in it and mounted it from beneath. The attachment to the coil is a # 2 welding cable end lug soldered to the primary coil and held in place with a brass 1/4-20 6" bolt and nut assembly.
 

The RF ground "lug" is HDPE 2" round stock drilled thru and tapped for 5/16" brass bolt. the bolt was machined a bit to remove the threads from the exposed portion above the HDPE. It was then drilled and tapped for 10-24 and a hole was drilled to pass the secondary wire to fit in. The set screw is tightened up to make the connection secure. I like this type of connection above better than any other connection I have applied in previous efforts. Its fast secure and low profile. Plus it is well insulated from the primary base.
 

Ever wonder what 30KV can do even when it is running thru 40KV rated cable????   The sand on the plywood moved away from the cable during a test run. Another anomaly I noticed while testing was that the cable near the ground (but slightly elavated) caused the light weight debris ( bits of dried grass and wood chips) to jump around and suspend itself between the cable and the ground.
 

Once I get the few items repaired after the catastrophy I had 04-14-01 I will post pictures of some streamers. BTW which were the biggest and brightest I have had to date. Initially the streamers were doing an easy 9 -11 feet, had a few primary strikes so I put up a strike rod to divert the primary strikes. The strike rod was 10' from the outer edge of the toroid and was getting consistant strong strikes to it. Occasionally the streamers would avoid the rod and go completely to the ground in a wide arcing formation ( estimated length 12? 14? feet)
 
 

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