Joined: Jan 2008
Posts: 23,642
Likes: 1,106
From: Mans of NC & SW UT Desert
Bikes: 86 Katakura Silk, 87 Prologue X2, 88 Cimarron LE, 1975 Sekai 4000 Professional, 73 Paramount, plus more
I am able to get most stuck posts out via using PB Blaster. I let it soak for a day or two. I install a junker seat on it, put the seat in my bench vise, and carefully rotate the frame. Note, you can damage the frame doing this, so be careful.
Out of a dozen stuck posts, this has worked 11 times. The 12th time is going to require cutting out the post.
I just removed one yesterday using the PB Blaster/bench vise method.
Note, this is with alloy posts in steel frames.