MOT core

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

Original poster: "Dan" <pbursa-at-cfl.rr-dot-com> 

Hello !
I am curious if someone here has experience with rewinding microwave 
transformer.
I cut of the I part of the core, removed old windings and split the E core 
in half so now I have two identical E cores .
Together they make 5.5 inches long, 4.15 wide and 1.35 thick core with 
about 1.72 square inches area...
This looks like I'll need over 400 turns on primary... this would require 
40000 turns for 12KV secondary and there is not enough space for this, I'm 
afraid.
My question is - if I use less primary windings (say 150 - 200), how it 
affect performance, core saturation, ...
I noticed that original MOTs primary was also less than proper amount of turns.
Also, since MOT core is welded together, how the weld affect the core 
losses and eddy currents? isn't the very purpose of using laminated core to 
minimize these loses ?
How about potting finished transformer in oil ?
Thank you in advance
Vladan