Hi Bert, Ok, as promised, here are the plans for “Terry's Lichtenberg Figure Maker”. Of course, I have not tested anything at all so it's just a “goofy idea” ;-)) But I think it may have a snow ball's chance in hell of really working if only a few hundred little details are worked out :o)) I specifically disclaim and release the idea to the public domain, so feel free to share it with any and all that may be interested. The patent attorneys will just have to go suck someone else's blood :-D I have sort of “scaled” things to equipment “I” have but nothing would be critical at all. Refer to the diagram at: http://hot-streamer.com/temp/TLFM.gif The right side is just a (-) 50,000 volt DC power supply of 0-3mA. I have two Bertan -50kV 3mA XR lab X-ray supplies so they are “my” choice. It has a protection filter setup of a bunch of trivial resistors and a capacitor. (Guess how Terry knows how to add this stuff now after blowing the smoke out of the power supply too many times already :-))) They really DO blow a LOT of smoke too!! Cough cough cough... But Bertans are pretty easy to fix...). The resistors and cap are made for 50kV so they are big and have some corona stuff... They are also independently grounded so nothing bad comes though the ground side (again ;-))) C1 is say 25 of those 150nF 2000V Geek Group caps in series for a nice 6nF at 7.5 joules of storage to be used later to “pop” this thing ;-) L1 is just basically a bunch of heavy wiring that will have some inductance at roughly ~~1uH. The important thing is that L1 and C1 are a tank circuit that when shorted by S1 (50kV high current spark gap switch) will ring like all hell!! So just a -50kV DC system that can shoot RF on demand. It may have to hold the -50kV for a day or so before delivering the RF “whammy”... Next we have the “cup”. This is perhaps a 2x2x2 inch polished acrylic cube with a 1.5 inch diameter hole bored into it 1.75 inches. That leaves ¼ inches of acrylic as an insulator which “should” hold off 100+kV. McMaster sells the cubes for $3 but the hole boring is probably a pain... We set the cube on a grounded metal base with oil filling the air gap. That is to keep corona out of that area which might be “bad”. Now we have a metal funnel with a very thin tube leading to the center of the hole in the cube. Corona shields protect the top of the funnel (not too important really) and the top of the cup (probably real important there). The power system basically charges the funnel and the thin tube to -50kV. This is where the interior -50kV charging comes from. I will diverge for a moment here. Acrylic stands about 400kV/in. For the typical figures of 1 inch thickness with the interior charged, we only have about 1/4 inch of insulation suggesting that the charge voltage is about 100kV max. Other work suggest that if the voltage gradient was just 1/5 of the breakdown, it would still “pop”. So perhaps the interior only needs to be charge to 20kV! Not sure about this but the charge voltage seems reasonable at 50kV. Just have to try and see. The stored energy is a volume charge so things are pretty goofy from what we normally deal with. Ok, now to add the charged volume inside the cup. We get some liquid casting plastic sold everywhere (probably many other possibilities here!!) and add the catalyst and put in in the funnel. A small ball with a string can act as a valve with 50kV of isolation so we can release the liquid into the cup. So we fill the funnel with the runny liquid plastic and turn on the supply voltage. The thin tube with perhaps a steel wool tip insures that the plastic leaving the tube is well in contact with the -50kV. We pull out the plug and slowly the cup fills with the -50kV liquid plastic. The voltage is supplied constantly and the top corona shield is “supposed” to keep it all charge without anything popping too soon :o)) Once the cup is filled with the -50kV liquid plastic. We let things sit for hours or days until the plastic hardens. Acrylic has a resistance of 10000000000000000 ohms so the charge is not in danger of draining off for about 60 years!! Now all we need to do is fire the switch. The charged interior of the cup is going to see a ~1MHz 100kV p-p signal that is going to “pop” “something” :o)) Hopefully, it will make a Lichtenberg figure. There may be a flammability problem with the liquid plastic so care may be needed there. Of course, the high voltage caps and such are pretty dangerous too. They need to “sit” in a safe area where no one will wander into things. I see no reason why the thing could not be scaled to almost any size aside from the cost of the acrylic cup and liquid plastic. A sphere may be the best choice for the cup... This system would leave the thin metal tube in the plastic but maybe it should work if only inserted a little bit too... The funnel corona shields and tube are “used up” in the process so they should be “cheap”. Commercially, the process would probably be best making “big and expensive” figures. But I think it could be easily setup to do many in parallel too. Plain mineral oil could be used for testing, but I think the oil would get blown all over everything during the “pop”... So lot's of little details but I “think” the basic idea is sound. Any comments, suggestions, flames, are welcome :-)) Again, unless the idea is obviously “hosed”, share it with anyone who may be interested! I find that the more people there are to add ideas, the better these things get. Cheers, Terry