Yea..the hammer technique will not work on ones surrounded by steel. The ones in the picture shouldn't be more then ferrite, tape,plastic(spool) an of course copper.



Hammering things...therapeutic since the invention of the hammer!

Edit: Last on in the bottom row on the right looks like it's got the steel around it. Usually it's only the bigger ones like that, but now an then some of the small ones will have it. Rare in my experience. as always..YMMV.

Sirscrapalot - Hammer time.