(word processor parameters LM=8, RM=75, TM=2, BM=2) Taken from KeelyNet BBS (214) 324-3501 Sponsored by Vangard Sciences PO BOX 1031 Mesquite, TX 75150 There are ABSOLUTELY NO RESTRICTIONS on duplicating, publishing or distributing the files on KeelyNet except where noted! March 2, 1994 BOLTBAR.ASC -------------------------------------------------------------------- This file shared with KeelyNet courtesy of Gerald O'Docharty. -------------------------------------------------------------------- Excerpted from "The Tesla Phile" newsletter of May 1985 written by the late Peter Lefferts. Provided by Gerald O'Docharty Feb. 1994 -------------------------------------------------------------------- BOLT BARRIER, compound for Tesla coils PURPOSE To have an easily castable compound for insulation that is tough yet slightly resilient so that stress cracks will not occur. Available kitchen materials and low melting point are very important. My primary use will be to cast insulation between the primary and secondary using cardboard molds. The object is to wind the primary closer to the secondary, depending on the insulation to prevent flashovers between the two windings. -------------------------------------------------------------------- MATERIALS Paraffin, shredded soft polyethylene (old, translucent, coffee can lids etc.) (maybe clean clear polyethylene sheeting commonly available. G.O'), salt, & two large pots... one of which will sit easily inside the other. These pots should be stainless steel or good uncracked glass-porcelain covered. -------------------------------------------------------------------- PREPARATION First step is to make up a high temperature double boiler where the inner pot sits in the water. Some sort of support is needed so the inner pot doesn't sit on the bottom. Put enough paraffin blocks in the inner pot to supply the expected need. The inner pot will have to be weighted down because the outer pot should have enough water added to come about an inch above the melted wax level. Boil the water while adding salt to it until no more salt will dissolve. this raises the boiling point for a better product, yet greatly decreases the chance of flames. -------------------------------------------------------------------- COMPOUNDING When the water is at a medium boil with most salt dissolved and the wax melted, start adding the slivers of flexible polyethylene (avoiding other plastics that are stiffer or make a white line when creased). Page 1 Stir every few minutes to prevent the poly from sticking to the bottom and browning the wax. When about 1/2 the poly appears melted, add some more. Add water slowly to the outside pot to keep the level an inch higher than the plastic level of the inner pot. As soon as a hint of cloudiness appears in the mixture, or the consistency of thin oil appears, stop adding poly, and heat and stir a little longer. -------------------------------------------------------------------- CASTING A mold of good dense cardboard, glued watertight sides and bottom with ample epoxy should be prepared well ahead of time, also seal any wire joints likewise. Do not use other plastics such as Acrylics as molds, practically all epoxies and hard magnet wire insulations will stand up to the heat and solvent characteristics of this compound. Pre-heat the mold cavity using an oven for small objects, or hair drier for larger ones. If oven, pre-heat it 250 deg.F. and wait until well stabilized before putting object in. If hair drier, heat until a metal part will sizzle slightly when touched by a wet finger. Be sure that if a Tesla primary is being molded that several taps for tuning are brought out through the mold. Also if you want to take the cardboard off later, smear the inside with silicone grease (easier to paint the cardboard though). Pour rapidly without splashing; this stuff burns skin worse than boiling water. Shake gently to bring up bubbles. If a small leak appears, patch with magic tape and blow with hair drier on cold setting until the plastic in the leak has well solidified. -------------------------------------------------------------------- FEATURES Bolt barrier is at least an 8 times better insulator than air. It can be carved quite easily and very smoothly, and in fact may make an excellent amateur's sculpture media. If done slowly, the material can be drilled and sawed with ease. It makes good light duty custom bearings for models etc. Almost any household solvent may be used for short term cleaning without effect...turpentine has some polishing action. -------------------------------------------------------------------- If you have comments or other information relating to such topics as this paper covers, please upload to KeelyNet or send to the Vangard Sciences address as listed on the first page. Thank you for your consideration, interest and support. Jerry W. Decker.........Ron Barker...........Chuck Henderson Vangard Sciences/KeelyNet -------------------------------------------------------------------- If we can be of service, you may contact Jerry at (214) 324-8741 or Ron at (214) 242-9346 -------------------------------------------------------------------- Page 2