Odds and ends

[Mark]

I just noticed Resbond 940LE might be a good candidate to use with my quartz tubing, There aren't many materials that have a lower thermal expansion rate that quartz/SiO2. Think about a spark plug having metal and ceramic in a tight fit together. They would have to expand at roughly the same rate I should think. I remember cracking a spark plug just dropping it on the floor.
http://www.cotronics.com/vo/cotr/pdf/940.pdf
http://www.cotronics.com/vo/cotr/pdf/940%20LE.pdf

[ace_fedde]

Mark,

If you remember having more about ceramics in this thread, can you copy it to the ceramics thread?
Thanks.

viewtopic.php?f=7&t=6301
(I fixed the link)

Fedde

[Mark]

Sure, if I remember in the far future. If not remind me.

[Mark]

This is kind of a curioius method if you need some silicone lengths. I'm going to try to get my store-bought fuel line silicone tubing to form a belt, so I have to connect the ends somehow. I want to use the belt on a small wimshurst machine I am planning to make. I tried some superglue that didn't hold very well and I put a small piece of flexible plastic inside each end as well sort of to give it added surface area to no avail. Maybe I could sew the ends, it can have a slight defect, it just has to go around some pulleys. I also tried a piece of lamp chain, pushing a few beads into each end. But they pull out if you pull hard enough. I was thinking maybe I could wind some thread around/between each bead over the silicone to hold them in there. Any other ideas welcome.
http://www.instructables.com/id/Homemad ... /?ALLSTEPS

[Mark]

I've been playing with my electrophorus, trying different dielectrics and thicknesses for the insulator to see which makes the best spark. I was wondering if you could stack different kinds of dielectric sheets and get some stronger effect. I tried using glass plate but it doesn't hold a charge like acrylic, after a few good sparks it just dies out. I ordered some teflon sheet to experiment with. Also if I connect an extention cord to the wall and use the ground plug for the electrophorus to discharge to when I lift an aluminum disc off the dielectric acrylic sheet, the spark is noticeably stronger by getting a good ground. An electrophorus is a kind of capacitor that keeps recharging itself everytime you lift it, in my case an aluminum plate off of a dielectric material/acrylic with another plate of aluminum under that. Once charged, you can continue to make sparks as often as you lift it. When I charge up the electrophorus for the first time, it sometimes really sticks to the dielectric acrylic, not wanting to let go, but then it makes a really zappy spark when separated by lifting the aluminum plate up with an insulating teflon rod, kind of a remora-electric eel effect. ha

Dielectric tidbit.
"The engineers demonstrated for the first time that in a capacitor made with a ferroelectric material paired with a dielectric — an electrical insulator — the charge accumulated for a given voltage can, in effect, be amplified, a phenomenon called negative capacitance. The experiment sets the stage for a major upgrade to transistors, the on-off switch that generate the zeros and ones of a computer’s binary language."
“There was an expected voltage drop to obtain a specific charge with the dielectric material,” said Salahuddin. “But with the ferroelectric structure, we demonstrated a two-fold voltage enhancement in the charge for the same voltage, and that increase could potentially go significantly higher.”
http://www.kurzweilai.net/ferroelectric ... -computing

Volta tidbit.
"To what electricity then, or to what instrument ought the organ of the torpedo or electric eel, &c. to be compared? To that which I have constructed according to the new principle of electricity, discovered by me some years ago, and which my successive experiments, particularly those with which I am at present engaged, have so well confirmed, viz. that conductors are also, in certain cases, exciters of electricity in the case of the mutual contact of those of different kinds, &c. in that apparatus which I have named the artificial electric organ, and which being at the bottom the same as the natural organ of the torpedo, resembles it also in its form, as I have advanced."
http://www.chemteam.info/Chem-History/Volta-1800.html

[Mark]

I "made" a jam jar today.

[Mark]

And now for the fine print. The purple jam jar in the previous post ran fine for almost ten seconds before it started heating up and inhaling too much smoke. I guess you could fix that with acetone, I noticed it removes the paint fairly well. The plumbing pipe reducer fitting screws in all the way but doesn't quite make a perfect air tight seal, although it's very close. The purple bottle was on sale for $2.39 at Hobby Lobby and is kind of rare, or harder to find because it's made of stainless steel with a "fine" threaded neck. Actually it looks like a press fit threaded ring is used and it's most likely an anodized aluminum that looks like brass sort of. There are even cheaper brightly colored water bottles for only $1.00 at some stores which are made of aluminum with the same threaded ring, perhaps you have seen them. These red, blue, and gray bottles might make a decent jam jar if water cooled or you could make a fire ring thrower perhaps.
I found some 1.25 liter stainless steel bottles that were very nice too, but they have the jumbo plastic lid threads. It's amazing how they appear seamless from the outside and very fine welds if you look inside, as fine as my Bailey Jet if not better. They are very light too. I got them on sale for only $4.00 at a pharmacy store. I hadn't seen anything larger than the liter size before. I like the look of the patina of the stainless steel bottles as well.
All of the bottles pictured are painted, even the silver one. And all but one are aluminum in this set. Again, nothing exotic in nature here, just fun stuff to prototype with or use for specific applications where simplicity is best.

[Mark]

Here's a couple of photos of the turntable turned electrophorus. There's a sheet of aluminum foil on the bottom used to ground the design. Above that is an insulating sheet of acrylic .100ths thick, then a heavy aluminum turntable with an insulating teflon rod to lift it, thus creating the spark. I noticed with my negative ion generator I power with a little 9 volt battery causes the electrophorus to behave differently depending on which aluminum surface I choose to attach the leads. If I put the insulated silicone wire lead on the aluminum foil it charges up the electrophorus and makes good popping sparks that way, some 2 inches long. But it will do the same if I put the negative lead on the turntable too. It is important to disconnect the tiny negative ion generator once you charge the electrophorus, for if you don't it will really shock you. One time I noticed such a charge builds up to make an interesting light show if you use an acrylic sheet that just fits over the two metal surfaces. It constantly arcs over to each aluminum surface with the acrylic becoming like a fiber optic cable, the entire edge all the way around the acrylic creates a blinking light show with sharp pops of electric light firing about 1 or two per second.
But to continue, once you have charged the electrophorus and disconnect the ion generator, you can ground it by touching the turntable and then lifting it to produce a spark. I think what happens is the electrophorus drains down to how you would normally charge the surface by rubbing it with rabbit fur as is done in the classic way. You can lift and spark for as long as you like and come back to it hours later and it will still produce a good popping spark without recharging. The odd thing though with the negative ion lead charged to the turntable and then disconnected as usual, you can also produce an occasional/often crackling fuzzy spark, some starting as far as 5 inches from my side which I have been shorting it out to. The spark has lots of fine branches and a barely visible blue light. And then after that effect, if you bring the electrophorus even closer it will sometimes/often produce a second spark, very strong and bright about two inches. The branching effect reminds me so much of lightning, all the zigzagging forks becoming finer and finer until a shower of a faint corona blue mist. It appears as if there are multiple launch points when I lift the disc and it does the longer distance crackle effect with the lights dimmed. The best sparks are produced by quickly lifting the turntable plate straight up.

[Mark]

So after building a few small electrophorus devices, I decided to scale up to this 16.73 inch diameter disc. I have to make a rod or something to lift it up and down and put a sheet of acrylic between the two plates for the dielectric. It's interesting to note with my previous electrophorus that the acrylic is really loaded with static if you remove it from the table and hold it next to you, a trapped charge of sorts.
Today I was toying with the two plates as a capacitor and a 100,000 volt device I bought on eBay. If you look between the plates when it's discharging, it looks like a fierce electrical storm on some miniature African horizon minus the acacia trees, bolts of light raining down all around and inside the gap of the aluminum discs. It's really quite extreme making many arcs per second and I noticed like pulsejets, the sound is kind of hard on your ears and lots of ozone is formed. It really improves the sparks compared to just watching my high voltage device jump across two pointed brass rods.
In a way an electrophorus is just a kind of capacitor that recharges itself, and you provide the lifting force to do that. And then I guess a Wimshurst machine is sort of like a rotating electrophorus. Further, some super capacitors kind of act like a battery.
If you put/bake in charged dipoles in your dielectric and/or metal plates you can form a piezo effect that also generates electricity. I was reading one way to make a charged material is to put a high electrostatic field on the mass as the material solidifies. And there are other ways too I vaguely recall as with the common piezo sparker and titanates. When I was in high school I checked out a book on growing crystals. One was rochelle salt. You could make a piezo effect after growing the crystal by placing two pieces of aluminum foil on either side of the crystal held in place by a little bit of vaseline rubbed on the crystal to make the foil stick. Then you padded it with cardboard and from the aluminum foil you attached two wires that your assistant held. By striking the crystal with a hammer, your friend gets a shock, all in the name of science.
Anyway, one thing leads to another. Here's the plates I was talking about, ordered from this company in California. (5/16 X 16.73 with 4 holes)
http://www.sandsmachine.com/alumweb.htm

[Mark]

“When you fantasize about it—especially when you fantasize something very positive—it’s almost like you are actually living it,” says Heather Barry Kappes of New York University, one of the study’s co-authors. That tricks the mind into thinking the goal has been achieved, draining the incentive to “get energized to go and get it,” she explains. Subjects may be better off imagining how to surmount obstacles instead of ignoring them.
The Pitfalls of Positive Thinking
http://www.scientificamerican.com/artic ... e-thinking

[Mark]

From Scientific American, March 7,1885
"Mr. Wimshurst has in his laboratory what is probably the largest collection of the most powerful electrostatic induction machines in existence, having worked for several years in perfecting this class of apparatus. We have in the illustration introduced (partly to serve as a comparison of size and partly to illustrate a very interesting and typical form of the apparatus) a sketch of what is perhaps the simplest and the cheapest electric influence machine ever constructed. This little apparatus consists simply of two disks of varnished glass, 12 inches in diameter, fitted with tinfoil sectors, and mounted on a spindle, which can be held in the hands, and the disks can be rotated in opposite directions by spinning them with the finger and thumb. When this is done—although there are no collecting combs or discharge conductors— the most brilliant effects can be produced, the whole apparatus literally bristling with electric discharges immediately the rotation commences, and one of the most remarkable and not the least valuable features of this beautiful little instrument lies in the fact that it can be constructed in a good, salable, and workmanlike manner and sold at a very small charge."
(Scroll down about halfway)
http://books.google.com/books?pg=PA150& ... utput=text

Or ...
http://books.google.com/books?pg=PA150& ... &q&f=false

[Mark]

So I am toying with building a sectorless Wimshurst machine otherwise known as a Bonetti. I'm using the plastic polystyrene for the discs. Note the tiny triangle recycling markings on the plates in the first picture which have the number 6 and PS below the triangle denoting polystyrene. I have seen a Wimshurst made from records so I thought what the heck, some picnic plates/Chinet dishes would be fun to try. I've a long way to go before completing the project, it's a lot of work believe it or not, finding parts that press fit together and lathing. You find by changing one aspect, you have to alter several others, much like pulsejet building. But I have some play built in, I can adjust the PVC pipes with magnetic clamps and the PVC fittings sleeve up and down the posts. The plates are spun slowly until I get them centered and then I "press fit" those on with suction cups. It was very funny when I did this the first time on the counter. First the plate was slowly spun until I got it centered then pushed down to afix it to the suction cup. I flipped it over after pressing the plate on top of the suction disc and just set in on the counter and when I went to lift it by the gray PVC with bearings/suction cup handle, the plate itself formed a vacuum and I had to slid it to the edge of the counter to break the seal. I would have never thought an upside down plastic plate would make a seal with the countertop - a vacuum cup holding the plate and the plate itself becoming a vacuum cup with the countertop. The other plate is the reverse, the suction cup mounted to the "inside" of the plate so that the two plates spoon together.
It still needs some things like the neutraliser bars, collectors, and belt system to make the plates counter rotate. I've made some rudimentary capacitors with the plates and aluminum foil and with clear plastic disposable cups as well, trying to stick with a theme. WIth capacitors you get better sparks, most Wimshurst machines have two. I initially started out making capacitors out of .100ths thick acrylic sheets and foil and thought plastic cups and plates would be fun to try. Now the plates are becoming discs. Funny how things evolved.

[Mark]

I suppose this would fall under more of "What manner of witchcraft is this?" ha

http://en.wikipedia.org/wiki/Pelletron

"In addition to being far superior to the belt-driven Van de Graaff, Pelletron charging systems also offer significant advantages over solid-state charging systems. These systems have fragile electronics in the high-voltage column that are prone to problems which are both difficult to diagnose and expensive to repair. Because they are susceptible to spark damage, solid-state systems require long times to condition up to rated voltage."
"Pelletron chains are made of metal pellets connected by insulating nylon links and are charged by an induction scheme that does not use rubbing contacts or corona discharges. For a positive terminal Pelletron, the negatively-charged inductor electrode pushes electrons off the pellets while they are in contact with the grounded drive pulley. Since the pellets are still inside the inductor field as they leave the pulley, they retain a net positive charge. The chain then transports this charge to the high-voltage terminal, where the reverse process occurs."
http://www.pelletron.com/charging.htm

"The Pelletron gets its name from the metal pellet charging chains which are highly efficient, provide long life, need little maintenance and provide extremely stable terminal voltage conditions."
http://www.pelletron.com/aboutnec.htm

Hope Pelletron
http://www.youtube.com/watch?v=Uq_qCwXxMPo
http://www.youtube.com/watch?v=j8Z3TY9gpVw
http://www.youtube.com/watch?v=HYlf4f7D ... re=related

[Mark]

Here's a healthy spark for you. It's funny how often I've been coming across those spheres/bearings with smaller spheres glued to them, an interesting design.
"This device is charged with a 3 1/2 foot long piece of 1-inch PVC pipe rubbed with a 1-foot long sleeve of the cheapest, roughest paper towel you can lay your hands on. I usually further wrap the bottom of the paper towel sleeve with a thick layer of cotton cloth to provide higher resistance so as not to bleed off too much of the charge to my hand, increasing the performance even more."
http://www.coe.ufrj.br/~acmq/foster.html

It certainly seems more fun than this film canister build below. ha
And note what the above author said about sharp points. "Therefore, the the charging setup can't have any sharp points, or the charge will bleed off through corona leakage as fast as you charge it up."
http://www.sparkbangbuzz.com/els/stat-gen-el.htm

[Mark]

So here's my humble attempt at the PVC high voltage experiment.
http://www.youtube.com/watch?v=CYk6fsqNBb8
http://www.youtube.com/watch?v=xFY6iKSDfpM