Aquadag Rx? homebrew anyone?

WebTV-Mail-16844-7560 Content-Type: Text/Plain; Charset=US-ASCII Content-Transfer-Encoding: 7Bit

Looking for a "homebrew" aguadag recipe.

Aquadag (as you probably know) is a colloidal, conductive graphite paint that is commonly found on tv CRTs as part of the high-voltage grounding system. Anyone who has ever opened up the business end of a TV and looked inside has seen it on the outside funnel portion of the picture tube.

Formulas found in literature are non-specific but generally describe the contents as "powdered graphite, tannic acid and water/alcohol, the mixture forming a "colloid". I'm wondering if there are any "homebrew recipes" anywhere out there. I was thinking of possibilities: mixing together water, powdered graphite and instant tea in a blender. Or graphite and extremely strong tea (boiled instead of proper culinary infusion procedure). Strong tea from boiling contains excessive tannic acid (very bitter, unpalatable).

Or perhaps powd. graphite (locksmith) and liquid from boiling oak leaves. [Did you see the movie "Kinsey"? He was a mainstream biologist that did work with "gall wasps" before his notoriety in sex research.] Galls formed by insects on oak trees contain high levels of tannic acid and have been used as a natural source for such tannins. Tannic acid is an ingredient found in formulations used in rural, primitive methods of tanning hides.

Anyone, do you know of a homemade recipe for making aquadag?

I am guessing that the finer the graphite particles, the better; so the locksmith graphite should work adequately. I do not understand the need for tannic acid, but since it is very soluable; i think your idea to use oak galls would be a better source than tea. Be advised that Acheson's Electrodag(R) 440 uses acrylic for a binder (nickel base), and they recommend acrylic lacquer solvent as an alternate thinner for their 114 and 440 lines (MIBK is the primary thinner). Their Electrodag(R) 112 is graphite-based and used acrylic as a binder with a density of 9.7 lb/gal (1.2Kg/L) and gives a sheet resistance of 20 ohms/square @ 1mil thickness; they say "do not dilute" (but their selsction guide indicates water as a diluent) and to stir product thoroughly or use a slow speed propeller; do *not* use a paint shaker or other high shear mixer as this could flocculate the product. Flash point is not indicated on their selection guide. Their 114 is also graphite based; their selsction guide indicates MIBK as a diluent. Density is 7.9 lb/gal and has a flash point of -1.6C.

I hope that this info is of some help.