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LAN_403

Conundrum

Sun Jul 11 2010, 07:09PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

shapelock/Polymorph works well for small assemblies, but use the lowest heat gun setting or it decomposes and results in a brittle mess.

Patrick

Sun Jul 11 2010, 11:30PM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

IntraWinding wrote ...

Here's a quote from Wikipedia:

Pure Paraffin Wax is an excellent electrical insulator, with an electrical resistivity of between 10^13 and 10^17 ohm metre. This is better than nearly all other materials except some plastics (notably teflon).

But I think most plain white candles are a mix of Paraffin Wax and Steric Acid (Octadecanoic Acid). Apparently Steric Acid is also an insulator (which surprises me since I thought acids where ionic conductors) but since I can't find anything as specific as the quote above about Paraffin Wax, I'd feel on safer ground with pure Paraffin wax. Apparently it comes in different hardness grades too. You should be able to buy it as supplies for the candle making hobby.

acids are only conductive if dissociated in water, if not there ions are not free to become charge carriers.
also the strong acids, (6 of them) fully disscociate in water, weak acids (there are millions of them, like LSD) like HF or steric, only partially dissociate and are weakly conductive even in water, and again not conductive at all if not in water.therefore the steric acid is largley irrelevent, also it is immobilized in the paraffin.

note:that many drugs are acids (Lysergic acid diethylamide) or are acidified one way or another so they dissociate and have a high bio-availability within our bodies.

quicksilver

Mon Jul 12 2010, 07:00PM

Registered Member #1408 Joined: Fri Mar 21 2008, 03:49PM
Location: Oracle, AZ
Posts: 679

OT digression:
I was unaware that parrifin had such a high dielectric constant: that puts a whole new light on the use candle wax.

Steric Acid is frequently used as both a lube and a protective coating in flake aluminum mfg. Ball milling Al will often produce a granular type of materiel if such a lubricant is omitted once the breakdown of the particles have reached a certain size level.
I would imagine that if Steric Acid had significant caustic properties that flake Al would succumb to it rather quickly. Obviously then there's a difference between a descriptor of "acid/base" and "caustic". Actually I had not known that ball milling would result in granular Al if a lubricant was not used unit I tried it. The microscopic level of Al(O2) would protect the particulate from further oxidization.

Patrick

Mon Jul 12 2010, 08:47PM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

quicksilver wrote ...

OT digression:
I was unaware that parrifin had such a high dielectric constant: that puts a whole new light on the use candle wax.

wait do you mean dielectric strength, or dielectric constant !?

quicksilver

Tue Jul 13 2010, 03:08PM

Registered Member #1408 Joined: Fri Mar 21 2008, 03:49PM
Location: Oracle, AZ
Posts: 679

"Strength" but I was just reading the above so I mis-spoke. I've heard that Silicone oil or Mineral oil is quite high in dielectric strength; perhaps twice that of wax. It would be interesting to determine how the "red paint" material was made. It's may be a hydrocarbon based paint as the thinner is xylene. I wonder if that could be imitated...?
It seems a shame that many of the high-priced electronic-store materials could not be reproduced.

Sulaiman

Tue Jul 13 2010, 09:01PM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3141

MOST IMPORTANT !
Have you tested the multiplier before you pot it?
You could test under cooking oil. Then wash with household cleaners and thoroughly dry it.

I ask because you may have a flyback with inbuilt diode(s), (i.e. pulsed dc output)
in which case a multiplier will not work.

Modern tv flybacks are 25 to 35 kV which would be a significant improvement.

2Spoons

Thu Jul 15 2010, 02:56AM

Registered Member #2939 Joined: Fri Jun 25 2010, 04:25AM
Location:
Posts: 615

To mix wax and glue I used a large pot on a hotplate and melted the parafin first, then chopped up the glue sticks, threw them in and stirred for a long time. Using a glue gun to pre-melt the glue would likely be faster. Viscosity is controllable to some extent by the ratio of glue to wax. More glue increases viscosity and melting point. For pure paraffin wax look for boxes of "preserving wax" (at the supermarket in my case) - this was the old school method of sealing jam jars before we had plastic screw caps.

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