Dale Seppa
03-22-2000, 07:24 PM
I just this morning learned that the supply of the large (8" - 198
mm O.D.) toridal coil forms is very finite due to the fact that
production, has/will be discontinued at some time due to the fact
that they have a different method (foam) to produce this item.
Based on information that I had previously received, the smaller
form (Rock-a-Stack, Blue Donut, 4 7/8" O.D.) has ALREADY been
discontinued, although I KNOW that some stores still have these.
I think this leads to two obvious conclusions:
1. If you want a small form, best get out right now and look for
the Rock-a-Stack set and put one (or two) set(s) away. I am
supposed to have some of the large ones coming and there should be
some around for a while.
2. If you have any interest in either size toroidal form for any of
the PPM plans available - start looking. I have a source where I
can get these wound, BUT, setup charge is $200 (or more) per size
and I hesitate to spend the setup charge to get a couple of units
when these sizes appear to be discontinued.
Certainly there ARE many alternative methods of construction, some
of them quite innovative, available at THIS site. BUT, most are
labor intensive and probably are less structurally sound that the
ones produced in one (or two) pieces. This is to say nothing of the
fact that some (maybe all) of the alternatives known to me do NOT
produce a perfect toroid. (Well sure - NONE of them are PERFECT
toroids - but you know what I mean.
And, now for a stupid question. Can a non-magnetic metal be used
for a liquid filled toroidal form without causing problems??
Bes to all,
Dale
seppa@rangenet.com
103 North Sixth Avenue
Virginia, MN 55792 USA
mm O.D.) toridal coil forms is very finite due to the fact that
production, has/will be discontinued at some time due to the fact
that they have a different method (foam) to produce this item.
Based on information that I had previously received, the smaller
form (Rock-a-Stack, Blue Donut, 4 7/8" O.D.) has ALREADY been
discontinued, although I KNOW that some stores still have these.
I think this leads to two obvious conclusions:
1. If you want a small form, best get out right now and look for
the Rock-a-Stack set and put one (or two) set(s) away. I am
supposed to have some of the large ones coming and there should be
some around for a while.
2. If you have any interest in either size toroidal form for any of
the PPM plans available - start looking. I have a source where I
can get these wound, BUT, setup charge is $200 (or more) per size
and I hesitate to spend the setup charge to get a couple of units
when these sizes appear to be discontinued.
Certainly there ARE many alternative methods of construction, some
of them quite innovative, available at THIS site. BUT, most are
labor intensive and probably are less structurally sound that the
ones produced in one (or two) pieces. This is to say nothing of the
fact that some (maybe all) of the alternatives known to me do NOT
produce a perfect toroid. (Well sure - NONE of them are PERFECT
toroids - but you know what I mean.
And, now for a stupid question. Can a non-magnetic metal be used
for a liquid filled toroidal form without causing problems??
Bes to all,
Dale
seppa@rangenet.com
103 North Sixth Avenue
Virginia, MN 55792 USA