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Re: T-minus 7 days and counting...
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> Filled remaining space to the top with NAPA brand 10w30 motor oil (I own
a
> NAPA auto parts store).
Probably don't need this much oil, but, since it is cheap...
> Here are more questions for you to ponder:
>
> 1 Does anyone have a formula for calculating the capacitance of a
> saltwater cap based on physical properties?
Standard capacity formula, You'll have to estimate the surface area of the
"plates"(i.e. the salt water) use 3.14 * (height*diameter +
1/4*diameter^2). I'd assume the glass is constant thickness. You'll have to
find the dielectric constant for glass somewhere (I'm too lazy to look it
up this morning, I think 5 might be an ok approximation)
>
> 2. We live in a rural area in Ohio. We have a water well and the
water
> is high in iron. Is this a plus or minus for these caps?
Higher conductivity is better, but the salt you add completely overwhelms
any contribution from natural minerals. Of course, if your caps work
especially well, you might consider specially bottling your water and
selling it to unsuspecting coilers.
>
> 3 In saltwater caps, I would assume the saltwater is the storage for
the
> charge. Would it be a benefit to use as large (or small) as bolt as
> possible? Or not important?
Larger bolts have several good side effects: less resistance to the salt
solution (more surface area); larger radius of curvature (less corona
because there aren't as many edges). By the way, metal tubing would work
better than all thread for this reason. Perhaps some brake line tubing?
Nice and smooth. Copper or brass would be better than steel in any case.
>
> 4 These rubber expansion plugs use a large rubber grommet that is
> squeezed between two steel washers. The washer on the top (outside) of
the
> bottle is actuall touching the glass (nothing else except for the
rubber).
> Does this pose a problem? I really can't see how it's just that the
plans
> I saw called for a plastic lid to be screwed on the bottle and I couldn't
> find a cap that would fit this bottle.
No real effect unless the washer has a sharp edge on it which might pose a
problem for corona or arcing. A little work with a small file to smooth the
edge would fix it. But, don't waste time fixing something that aint broke.
>
> 5 The plans called for wrapping the exposed foil on the outside of the
> cap with at least two layers of electrical tape. Why is this when if it
> would get next to another bottle this would just be the ground anyway?
> Wouldn't it be better if all the bottles touched anyway?
Probably the tape is just to keep the foil on. A more traditional form of
the cap puts all the bottles in a dishpan full of salt water, and does away
with the foil on the outside. If you have some of that aluminum tape used
for heating ducts (basically it is sticky aluminum foil) that works really
well. If you have an infinite budget, use that really nifty copper foil
tape from 3M. Even the adhesive is conductive.
>
> Sorry for all the questions we're both just here to learn as much as we
can.
Don't apologize.. If you don't ask, you don't get answers (right or
wrong)..