Re: cardboard tube

["Steve" <Steve-at-xxxxxxxxxxxxxxxxxxxxxxxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

I have used cardboard mailing tubes for a number of tabletop coils, as well
as PVC and HDPE. For similar size coils and inputs, the outputs in terms of
spark length weren't very different, well within what might be termed
experimental error. For many years Paxolin was used for RF coil formers.
Paxolin is a resin bonded paper, not so very different from cardboard
impregnated with PU or shellac. Personally I feel that if the cardboard is
of reasonable quality, and is dried before treating with PU, then I don't
think it is a problem. I've never even bought a tube, I get them free at
work from received post. The one thing I will say is that they do vary in
quality, and I only use the harder type cardoard. After drying, I either use
a couple of coats of PU diluted 50:50 with white spirit, or soak the former
in the mixture.
----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, November 05, 2000 4:28 PM
Subject: cardboard tube


> Original poster: "Albert Hassick" <uncadoc-at-juno-dot-com>
>
> I stand by my suggestion to use a cardboard tube for a beginning or
> somewhat advanced coiler.  The tubes are cheap, easily obtained, and very
> easily prepped with suitable coatings to withstand moisture and abuse.  I
> am now finishing my secondary on a 12"diameter "QUICKTUBE" form with
> #14ga. solid wire that will be the drive coil for the tertiary magnifier.
>   If these cardboard tubes are sealed appropriately, then they will work
> just as well as a plastic tube....  Now, lets see, plastic tubes are made
> from various forms of what?   Well hydrocarbons of course.  Anything made
> from earth derived oil or plant derived oil will share one common bond,
> and that is, they are both made from hydrocarbons, and the key word here
> is 'carbon' in its many shapes and forms (SO THEN, I ask you), do you
> really think that when you use a plastic pipe that it is really superior
> to a cardboard tube?     I will tell you this: Place a nice big piece of
> nice white or black abs, cpv or cpvc, green or whatever color plastic
> tube in  the microwave, you will see that these tubes also heat up in
> your microwave, does this mean they are full of moisture?    AL.
>
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