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Component Sources mainly for UK coil builders.

This is the latest update as always I'd welcome any input . Some of this may be of interest to others outside the U.S.A.

BOOKS

Duane Bylund: Modern Tesla Coil Theory

140 pages - good on theory and practical - covers valve (tube) and solid state designs as well as Spark Gaps. (poor quality print - great content) $19.95 This is the must have book for solid state coiling.

Marty Brown: Power Supply Cookbook, (Motorola)

This is best book I've found on designing switching power supplies, it's almost entirely relavant. Of the 230 pages, pages 25 to 126 are concerned with PWM switching. The main circuit is built around the MC34025 which is the Motorola equivalent of the 3825. It includes flyback designs scaleable from 25 to 150W (probably more) and half bridge designs (280w example) again scaleable. There is a great section on designing magnetic elements. Page 128 to 162 introduce quasi - resonant switch supplies, again with practical examples. The appendices include more on magnetics and a wire table. It says that it is written for electronics engineers but I found it quite readable, and sufficently detailed. It is a cook book - it takes you right through the whole design process.

I got my copy from Amazon US for $24 plus $12 P/P, to the UK. I used the mid price shipping option- air to UK, followed by Post Office, it came in two weeks. Surface mail from US is incredibly slow - avoid. US books are slightly cheaper than UK which makes up for the shipping costs. There is no custom duty or vat on books.

Linsay Publications - New York

Tesla Coil by George Trinkaus 24 pages, very home brew but cheap and well presented. $4.95

Tesla Man out of His time: Margaret Cheney - good biography of Tesla $5.95

Tesla Coil Handbook - Todd A.Pringle 60 A4 pages - well presented should get you up and running. $9.95

TESLA COIL CONSTRUCTION GUIDE - 75 pages - $18.00 List

Contains plans for building 5 different coils with spark lengths fromone inch to 8 feet. All of the plans have been designed using the latest Tesla coil engineering technology and are based on actual coils built and tested by the author and other coilers. A unique step by step design procedure and graphs are shown for designing Tesla coils using manual calculations for designers who do not have a computer. The Guide contains 19 Sections and 37 Illustrations.

General Components: see the links

TRANSFORMERS

Oil ignition transformer can be found apparently from yellow pages heating engineers. Not so many neon's though - planning restrictions means we don't have so many here. New these tend to be about L50 so scrounge old ones.

Another alternative is to use two transformers salvaged from old micro-waves: Microwave transformers have one end of the secondary attached to the transformer core and earth. With two transformers the secondaries are combined at the earth. To get the EHT to combine you have to get the phase right, so swap the connections to one of the primaries. Gives about 4.5kV at 500mA.

If you centre earth then neither transformer is seeing more than its design voltage. Some one on the list reported that they had used them with the secondaries floating and used up to 4 in series - under oil I think. At least 3 folks in the UK have obtained polepigs from the electricity board. (Ask for the transformer repair dept) Julian Green wrote: I rang around the electricity board to get a pole pig. In the end I got 2 for 30 quid (sold as scrap). If you want to get one then the department you need is the transformer work shop where they re-furbish used transforers. 5KVA or 10KVA pole transformers are scrapped these days as their rating is too low. If you ask them nicely they will change the oil and give them an insulation test before they give them to you.

The type you want: Single Phase Primary 11Kv Secondary 240V 5KVA or 10KVA (dont ask for anything bigger as still use these) Explain you want it for tesla coil use or scientific experimentation else they will think you want it to steel electricity from the HV overhead cables.

A new 10Kv 100mA NST from Tunewell Transformers is £108.50 + vat. see

http://www.tunewell.com/

Warning: these transformer are one touch lethal.

A source of reasonably priced tungsten rod (TIG electrodes) up to 6mm dia. by mail order. see http://www.johndavies.co.uk/tungsten.htm

CAPACITORS

Haven't found any regular UK sources. Mine were all one offs. You could import from the states - ask the list for sources or build your own - Polythene sheet is available in Do It All, beer bottles make a cheap first capacitor. Do it all and BnQ also have polystyrene sheeting 2.5mm (avoid acrylic - heating lossy) Or better still build an multi mini cap - see my mmc page

COIL FORMERS

4" diameter PVC is widely available at builders merchants, - fine for a first coil. I've also seen 6" plastic sewer pipe (3m for £22) I scored a couple of useful pieces of 6" pipe and 1' foot pipe watching for spoil heaps left by the water board, and some more 4" pipe left by the cable tv people - ask the workmen. Someone else scored 7" polythene pipe from the gas board - as was. I've also wound a coil round a 5 gallon polythene bucket sold by Boots. It gives a 1 foot arc from my solid state drive Boots also do a barrel - both are meant for home beer making. Some one on the list has a coil wound on two waste paper baskets stuck together. Large plastic food barrels are another possibility.

Toriods

Do It All have 4" flexable Aluminium ducting. And the grey foam pipe lagging in 1m lengths - wrap round a plywood disc and cover with aluminium foil tape - Al tape from from RS, Farnell or Halfords ( Halfords is dearest option).

Spark Gaps.

Builders merchants will supply copper pipe in wider diameters. Most tool hire places will have a pipe cutter - much easier than a hack saw. Misc Look out for scrap - my daughters hair dryer just blew but the motor and fan will do to quench a gap.

These tips come from MIke Harrison:

"Wickes DIY shops do some nice 4" ali. dryer duct for toroids.

RS do some nice cheap Aluminium adhesive tape to wrap it with. 45metres x 50mm, 40 micron 176-567, 30 micron 176-573, UKP 5.62 and 3.75 respectively.

RS also do thin (4, 5, 6 and 8mm) copper tube for primaries, but it's NOT in the obvious plumbing section (which only goes down to 8mm), but in pneumatics. 4mm is 846-503 (10M, ukp8.54). Wish I'd spotted this before struggling with my 8mm stuff!

Farnell's industrial catalogue also has 4,6 and 8mm - 10M of 4mm : 702-0247, ukp11.27

The big B&Q 'warehouse' branches stock a reasonable range of steel, brass and alu. rod, bar, tube, angle etc. in 1M lengths for general construction work - strikerails, busbars etc., plus some plastic sections and sheet.

For coil formers, keep an eye open for roadside gas main repairs - there seems to have been a lot of replacement work going on recently, using yellow polythene pipe in a range of sizes from about 4" up to about a foot dia. They tend to cut and weld it on-site, so it should be possible to blag some offcuts."