View Single Post
  #6   Report Post  
Old May 8th 07, 04:36 PM posted to rec.radio.amateur.boatanchors
Chuck Harris Chuck Harris is offline
external usenet poster
 
First recorded activity by RadioBanter: Jun 2006
Posts: 270
Default Transformer rewinding

Bill Janssen wrote:
RapidRonnie wrote:
On Apr 26, 5:55 am, "Gary" wrote:

Power, plate, audio, chokes. Email me direct for a quote.

--


Why reuse nasty old lams when new are so cheap? You'd be better to
wind something some one wants on a production basis.


Where can I buy EI laminations for a 100 Watt transformer. I need to
re-wind a couple
of secondary windings on an existing transformer. I don't think I can
remove the existing
laminations without destroying them :-(

Bill K7NOM


De laminating a power transformer is usually pretty easy... That is,
as long as they haven't run a weld bead along the side to prevent
buzzing.

What you do if first knock out the wooden wedge that holds the
lamination stack firmly in the center of the cardboard bobbin.
Then you take a thick(not flexible), sharp, putty knife, and force
it under the tongue of the first lamination that was under the
wedge. The varnish will snap easily. Next, force it under the
top, or bottom leg of the same lamination "E", and move the putty
knife around the full circumference of the "E".

Keep the knife blade flat against the lamination to minimize any
bending. They all should peel off pretty easily.

-Chuck