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rolled capacitors

Subject:  rolled capacitors
  Date:   Sun, 20 Apr 1997 20:17:15 -0700
  From:   Gary Weaver <gweaver-at-earthlink-dot-net>
    To:   tesla-at-pupman-dot-com


ROLLED CAPACITOR DESIGN

Plate demention for rolled oil filled capacitors.

.01 uf capacitor 10" x 108" aluminum plate with a 1" x 10" tab.  A =
1080

.005 uf capacitor 10" x 54" aluminum plate with a 1" x 8" tab.  A = 540

.0025 uf capacitor 10" x 27" aluminum plate with a 1" x 6" tab.  A = 270

All aluminum plates are .010 aluminum flashing.  Bend the tab out to the
side 90 degrees so they will stick out of the capacitor
after it has been rolled up.


Polyethylene dementions for rolled oil filled capacitors.

.01 uf cap 14" x 222" long 9 layers of .006 mil polyethylene.

.005 uf capacitor 14" x 112" long 9 layers of .006 mil poylethylene.

.0025 uf capacitor 14" x 58" long 9 layers of .006 mil polyethylene.


Direction.  Place the 9 layers of polyethylene on the floor and lay 1
aluminum plate on top.  Fold the poly over on top of the
aluminum plate. Make sure the tab is on the opposite end away from the
poly fold.  You should now have a sandwich with 9
layers of poly on both sides of the aluminum plate.  Make 2 of these. 
Place one sandwich on top of the other with the tabs at
the same end.  Make sure one tabs points to the left side and the other
tab points to the right side.  Roll the cap up starting at
the poly end that is folded.  Roll very tight and put them in a PVC
pipe.   All capacitor will fit tight and you will have to spin the
rolled cap in the direction of the roll while inserting it into the PVC
pipe to make it go in all the way. 

.01 uf cap will fit perfect in a 6" x 16"  PVC pipe.

.005 uf cap will fit perfect in a 4" x 16"  PVC pipe.

.0025 uf cap will fit perfect in a 3" x 16"  PVC pipe.

After rolling the capacitor up there will be 18 layers of .006 mil
polyethylene between the 2 aluminum plates.  d = .108


Drill a # 7 hole in the center of the PVC end caps and tap the holes 1/4
x 20 threads.  Drill and tap a hole in only 1 end cap
per capacitor for 1/8" NPT pipe threads for a vacuum hose connection.  
Use a paper punch to punch a 1/4" hole in the end of
the aluminum tabs.  Put a 1 1/2" long 1/4" x 20 bolt threw the hole in
the tab and screw it in the hole in the PVC end cap from
the inside.  Tighten it against the plastic on the inside.  Put a hex
nut on the outside an tighten it against the plastic also.  Put
some lock tight on the threads to hold the hex nut in place.  Use a hot
melt glue gun to seal around the hex nut on the outside.
Put glue on both the PVC pipe and the PVC end cap and assemble them. 
Tap the end caps with a rubber hammer to make
sure they go on all the way.  Let the glue dry for about 5 minutes.

Connect a vacuum pump to the 1/8" NPT pipe threads in the PVC end cap. 
Pump a vacuum on the capacitor.  Hold the
vacuum a minutes then close the valve to the vacuum pump and open the
valve to the oil container to back fill the capacitor
with transformer oil.  This will take only a few minutes.  Remove the
vacuum hose and plug the hole with a socket set screw
type pipe plug.

.01 uf capacitor construction time is about 2 hours and the cost is
about $42.00.

.005 uf capacitor construction time is about 1 hour 30 minutes and the
cost is about 22.00.

.0025 uf capacitor construction time is about 1 hour and the cost is
about $15.00.


The capacitor is now ready to use.  All capacitors are rated 40,000.
volts.

Formula  C = [(.224 x K x A)  / d] x 2    k = 2.3


Gary Weaver