RE: home-brew tranny, and depotting NST's

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Duke, Ronn (CCI-San Diego CCC)" <Ron.Duke-at-cox-dot-com> 

	Steve,
 	I have rewound a 15/60 Franceformer that I damaged trying to unpot
it. I wanted to do it anyway just to see if I could build a better mouse
trap, so to speak. I built an automatic winder with a turn counter and auto
feed with common materials. Fiber shelving for the frame(the stuff with the
white primer already applied at the home improvement stores), inexpensive
skate boards bearings for all the rotating parts, various belts and pulleys
from the surplus stores. The transformer I did had a double "E" core,(which
is most NST's), and approximately 10,000 turns on each secondary, 100 turns
per layer -at- 100 layers. It was wound with 34~36 gauge wire but I wound it
with 30 ga. that's the thickest wire I could use with the space available
and still get the number of turns I needed.  With Kraft paper from the
hardware store(used for masking) for in between layers, I wound the coils
bigger than original. I removed all but 8 shunts on each pack(had 22 in each
originally), so I would still have a little current limiting. This gives me
a little more room for the coils to fit. I remounted it in a modified ammo
box(military surplus), in an oil bath. It tested out at about 325ma output,
but I have not checked the input amp draw yet. I also have not tested it in
battle, but that is forthcoming.  I used the existing primary which was P.F.
corrected(dual primaries with a 4.3uf cap). All I have to work with is some
hand power tools and a drill press. It will take some time but it beats
spending 6 months looking for another NST, and you could build it with more
power(Arr, Arr, Arr).
Here is a site on winding transformers that might help:
http://members.tripod-dot-com/~schematics/xform/xformer1.htm
<http://members.tripod-dot-com/~schematics/xform/xformer1.htm> 

Happy winding.

Ronn
(Teslamanian Devil)

<Snip>
	Original poster: "Stephen Carpenter" <sjc-at-carpanet-dot-net> 

	On Thu, Dec 07, 2000 at 07:29:21AM -0700, Tesla list may have
written:
	> Original poster: "Chris Dobson" <cdobson-at-microtech-dot-com.au> 
	> 
	> Hi all,
	>  
	> A couple of questions : does anybody have much experience winding
their own
	> trannies, especially on straight cores, and secondly, what is the
best way to
	> depot an NST . . . I cooked one in an oven, but the enamel on the
primary
	> windings (which is what I wanted) got carbonised and therefore
U/S. Any
	> comments?