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

Re: primarys (how to wind flat coils)




From: 	Chip Atkinson[SMTP:chip-at-XiG-dot-com]
Reply To: 	Chip Atkinson
Sent: 	Wednesday, November 05, 1997 2:10 AM
To: 	Tesla List
Subject: 	Re: primarys (how to wind flat coils)


Another method is to make "combs" with either a slot tooth profile, or a
semicircle profile.  I have done both.  I cut the strips to the correct
dimension and put the teeth in using different methods, depending on the
desired profile.  

For slots when making a ribbon primary I use a table saw, since that's
what I have.  A radial arm saw would be easier, a hand saw harder, but it
would still work relatively well.

For semicircles, I use an end mill and a drill press.  I set up a
pair of fences on the drill press table to prevent the material from
moving.  I used an end mill because I had it.  If I didn't, I would have
sawn the comb material a bit wider so that I could drill a row of holes
entirely in the material.  (The problem is that if your hole doesn't fall
entirely within the material, the drill will wander).

With the end mill, I was done in one pass.  If I used a drill bit I'd then
saw the edge off the combs to produce a piece with a bunch of notches.

(Of course you should use a drill or mill the same diameter as your
tubing, and the comb material should be thin enough so that it doesn't
really affect the radius of curvature in your primary.  I find 1/4" (6mm)
works well.)

Here's a great trick that I discovered a while back:  Saw (or mill) so
that the center of the holes is about 1/16" (1.5mm) (roughly) behind the
edge of the comb material.  This way you get a notch with the profile
close to a "C", rather than a "(".  The advantage of this is that you can
then snap in your tubing as you coil it up and it'll stay in place.


Chip
---------------------------------------------------------------
Chip Atkinson; Xi Graphics 1801 Broadway, Denver CO 80202
(303)298-7478voice (303)298-1406fax (800)946-7433sales
---------------------------------------------------------------