[Prev][Next][Index][Thread]

RE: Primaries and Copper Tubing

Subject:  RE: Primaries and Copper Tubing
  Date:   Fri, 18 Apr 97 22:26:19 UT
  From:  "William Noble" <William_B_Noble-at-msn-dot-com>
    To:  "Tesla List" <tesla-at-pupman-dot-com>


The method I used to make a flat pankake was painless, but maybe a bit
more 
expensive than the one ken smith proposed:
1. use acrylic sheet for base plate - it's an insulator to start out
with - I 
used 1/4 inch X2ft square - cost a bit under $30
2. glue a 1/2 inch length of 6 inch pipe (or acrylic tubing) in the
exact 
center to form the inner diameter of the coil
3. drill a hole through the acrylic next to the 6 inch pipe for your
inner 
feed
4. pull pipe (about 18" of it) through the hole and fold on both sides
to lie 
flat - make about a 1.5 inch radius bend to avoid an ugly looking (and
maybe 
electrically bad?) kink
5. wrap a turn of pipe around the 6" pipe.  start the spiral outwards so
you 
clear the beginning by 1/4 inch.
6. make a whole bunch of 1/4" spacers - I used 1/4 inch square acrylic
stock - 
it cost about a dollar for 6 feet - get two 6ft lengths, cut to 1/4 to
3/8 
inch long for spacers.
7. glue the spacers around the pipe you have laid down.  I used solvent
based 
glue - it sticks quickly and is much stronger than hot melt, and doesn't
stick 
to your fingers like cyanoacrilate (superglue).  A spacer every 30
degrees or 
4 to 5 inches seems to work fine.
8. repeat for each turn - I used a large "clothespin" type welding clamp
to 
hold one turn tightly against the previous while the glue dried.  I made
2 or 
3 turns a day for a week.  I stopped when I ran out of pipe (50 ft) at
13.5 
turns
9. grind a 1.5 inch piece of the acrylic stock so one end will fit
inside the 
outer end of the pipe while the other end will lie flat against the
base.  Use 
this to hold the end of the pipe down.
10. glue 3 or 4 pieces of acrylic radially from the inner piece of 6inch
pipe 
across the top of the coil to the outer edge.  Glue the radial pieces to
the 
inner pipe and all the spacers that it crosses.  This will keep the coil
from 
falling off (embarassing).

I was thinking about how to do this cheaper - came up with this idea -
use 3/4 
pvc pipe - put a 1/4 inch dado blade in the table saw.  make 6 (or 8)
lengths 
of pipe that are 12" long (average) and whose length differs overall by
1/2 
inch - e.g. for 1/4 pipe on 1/4 spacing with 8 lengths, each length will
be 
1/16 longer than the previous - you will start at 11 3/4 and end at 12
1/4.  
Now, stick all of the pipes together, set the dado for a 3/8 inch deep
cut and 
make a cut every half inch along the set of 8 pipes.  When you then take
the 
ends of the pipe that faced away from the fence and glue them to the
piece of 
6 inch pipe you will use for an inside radius, the notches will form a
nice 
spiral.  And, since the notches are fairly deep, there should be no
problem 
getting the pipe to stay in the notches - a scrap of PVC pipe with some
PVC 
glue could secure the pipe if you wish.

-----Original Message-----
From:   Tesla List 
Sent:   Thursday, April 17, 1997 6:46 PM
To:     tesla-at-poodle.pupman-dot-com
Subject:        Re: Primaries and Copper Tubing

Subject:  Re: Primaries and Copper Tubing
  Date:   Fri, 18 Apr 1997 05:01:47 -1100
  From:   Ken Smith <ksmith-at-ihug.co.nz>
    To:   Tesla List <tesla-at-pupman-dot-com>


At 22:56 16/04/97 -0500, you wrote:
>        Right now my back hurts,  and I am frustrated,  and I'm looking
>for advice and inspiration;  and I don't even want to see
>any copper for about 24 hours.
>
Brendan
         welcome to coiler's world. What follows is my best shot at
primary
construction methods.  [Bill]  SNIP