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I need advice



Original poster: "Drew Murray by way of Terry Fritz <twftesla-at-uswest-dot-net>" <drewallmighty-at-hotmail-dot-com>

hello,
I have made two attempts at building a tesla coil. Only one of them was 
successful. My first coil consisted of a 1 1/2 pvc pipe for the secondary 
which was wound with 18 gauge motor wire. the primary was made with house 
wire. I also was using two salt water filled, tin foil covered two liter pop 
bottles for capacitors, and for my hv pwr supply i used the guts out of an 
old computer monitor. It sucked. but i did learn a lot about what not to do 
when building a tesla coil. I also learned how bad it hurts to take a 
charged capacitor through the chest.
My current coil is functional but needs improvement. I wound the 3 inch abs 
pipe with 24 gauge magnet wire that cost me around $60 at electric motor 
services in Fredericton New brunswick. Overall there were 657 turns on the 
secondary. I bought an end piece that fit on the bottom of the secondary so 
i could mount it to the wooden stand i made for this coil. My primary coil 
consists of 50 feet of quarter inch soft copper refrigeration pipe. I got 
this from Oromocto plumbing at cost for $23.75 (can). I currently have it in 
a bowel shaped coil which is at a 22.5 degree angle. I once had gotten five 
oil burner igniters from a repair guy but i burnt out every one of them. The 
way I see it, any XFMRs with tar insulation suck. They suck, they suck, they 
suck. To get the tar off of them you need like a lot more gasoline than my 
father would let me turn black. At school when i was rummaging through the 
storage room in the back of the physics department i found a 5000 v 16 ma 
transformer and a top off of a van de graff generator. There is no tar on 
the Xfmr and I have been using it for the time being. It has not died. I 
don't have any chokes hooked up to it or any thing. I did manage to get it 
smoking once but it survived to power my coil for another day. My capacitor 
consisted of seven wine bottles in an eleven and a half liter home hardware 
bucket lined with tin foil. I filled the bucket and the bottles to the same 
level with super saturated salt water. It worked but not very well. Salt 
water capacitors suck. They are extremely messy especially if you have 
poured motor oil on them to minimize corona discharge. Ever try taking one 
of those suckers apart. Big mess! At around midnight i finished cutting the 
tops off of 123, 1 gallon zip lock bags, and cutting out sheets of tinfoil 
with a tab on one end so that they fit inside the zip lock bag with around 
an inch of clearance on all sides. I have heard of this design once before 
and it sounded very good so i started to build one. Now all i have to do is 
find some mineral oil and a vacuum pump.
As for transformers, i need advice.
The guy who manages the surplus stuff at the local power company sent me a 
list of transformers that he has available and i need advice on which one to 
choose. Cost doesn't matter because they are being donated to me because i 
am building this coil for school and i am hoping to win a science fair in 
march with it too.
This is the list as he sent it to me, i have no additional information.
TRANSFORMER ignition 120v 10000v 250va type g
TRANSFORMER potential 12000v :120v indoor type pv15f
TRANSFORMER distribution 12470grdy/7200v 120/240v 3kva 60hz oil filled 65c 
rise type onan
also, an estimate on how much they weigh would be appreciated as well.
I have been lurking around reading up on tesla coils for about 5 months now 
and i have found myself in serious need of good and accurate help.
Oh i forgot to mention, My current coil running on a 5000 v 16ma XFMR with a 
seven wine bottle salt water capacitor can produce 6 inch sparks to the tips 
of my fingers. I am using a small air compressor for a simple air blast 
spark gap. It works well.
Any help at all would be appreciated.
                                             Up in canada,
                                              Drew Murray
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